emc-users — Messages about installing and using EMC

Re: [Emc-users] setting up dual PID loops for servoencodersandscales

[gene h. <ghe...@sh...>]

On 4/22/26 17:09, andrew beck wrote:
> hey guys
>
> finally made a thread on the forum
>
> lots of photos and this youtube video
>
> for those that are interested
>
> cheers
>
> https://youtu.be/AmQGh_Cwff0?si=ZIihICf10Gto2px7
>
>
> https://forum.linuxcnc.org/show-your-stuff/58689-large-fil-cnc-machine-retrofit-12-ton-larger-maching-running-linuxcnc#345849
>
>
> andrew
>
> On Thu, Apr 23, 2026 at 7:37 AM andrew beck <and...@gm...>
> wrote:
> Hey guys
> thanks for the replies
>
> the homing is a interesting issue
>
> I had a bit of a play and made a copy of my config that i hacked.
>
> What i found was that if i combined my original 2 PID loops into 1 loop
> and used the scale for position and used the motor velocity on encoder for
> velocity all in one PID then homing to index enable worked perfectly
>
> but doing it that way the motor tuning was not as good.  backlash is a
> constant of 0.1mm and the motor just jumped across that backlash whenever
> it moved.  in practice that meant that the absolute scale position hovered
> by +-0.01 or so.
>
> this was not bad and totally usable.  If i had done this option first i
> would have called it good and just used it.  but the movement was much
> louder and less smooth than the two PID loops which get run through a sum
> component.  As the original two PID loops was much much smoother, it was
> perfect and once i come to a stop the drive rapids to within 0.01 or 0.02
> and then creeps the last 0.02mm (using the integral value which takes about
> a second)  and ends up in the right place within 0.005mm or less.
> basically perfect every time with no dithering.
>
> It is now my most accurate machine.  and really nice
>
> also the homing when homing I home all axis at the same time.  X and Y get
> homed to index enable like normal.
>
> and the Z value i trick the home switch by checking the joint state.  How
> this works is the Joint2 switch state goes form 7 when searching for switch
> the first time to 12 when latching on to switch slowly the second time
>
> so in classic ladder i set up two compare functions that basically choose
> whether to listen to the main home switch or the z axis motor encoder Z
> index pulse.  (this is different to the index enable pulse and this is
> possible to miss when only checking in software not hardware.  but at a
> slow speed i haven't found any issues yet, and when testing with a dial
> indicator i can't see any changes between homing.  I can rehome linuxcnc up
> the top of the travel beside the home switch and then rapid down to the
> table which is about 1m away and the dial indicator is definitely within
> 0.01 each time.  i can't really see any movement on it.
>
> So pretty happy all in all would like to fix the index enable issue in the
> future but for now it's working fine.
>
> this is a 40 year old machine and weighs 12 ton.  and when i got it the
> backlash was 0.40mm.  I replaced all the thrust bearings and changed from
> reduction gearbox to a nice mazak flexible coupling and direct drive  The
> timing belt was T8 timing belt so not even HTD profile which has more
> backlash which didn't help.  The FIL factory actually got the location of
> the Z axis 2nd ballscrew mount out by 2.4mm which i was shocked by.  i
> double checked measuring against the slideways at the top and bottom of the
> screw and yeah it was out 2.4mm from factory!  so that is why all the
> thrust bearings were stuffed.
>
> anyway just about to get it running into production.  this machine will be
> running like 16 hrs a day shortly probably.
>
> cheers
>
> Andrew
>
>
> On Thu, 23 Apr 2026, 5:11 am gene heskett, <gheskett@shentelnet> wrote:
>
>>> On 4/22/26 10:44, Dave Engvall wrote:
>>>> Hi Andrew et al
>>>>
>>>> I have a cinci contourmaster set up with US made glass scales and a
>>> rotary encoder on the ballscrew. I’m in transition to stepper-servos but
>>> progressing slowly.
>>>> When I started this process I did a manual check with the hand crank vs
>>> the X axis scale. Proceeding in the positive direction I manually moved in
>>> 1” increments, ie 4 turns of the hand wheel. Even in this early 1960’s
>>> machine the glass scale was dead on. Since I’m protective of the US scale I
>>> removed it and installed a Chinese scale.
>>>> Both scales have a reference channel spaced with markers 50 mm apart I
>>> suspect the US made scale has guard ticks either side of the reference
>>> mark. I know the Chinese one's do.
>>>> Homing procedure was simple. I installed a laser diode and a tab with a
>>> hole in it at the end of the axis and manually homed to that before kicking
>>> off a home of the machine. Z was done by manually moving Z to the upper
>>> stop. If I positioned the tab and or Z stop correctly it never had to move
>>> more than ~ 3 mm to index. All of this used the normal homing procedure.
>>> Scan past the index and capture the position of index then move as
>>> necessary to home. It is my impression that homing should be done in that
>>> manner and not dual channel but after homing position seeking uses both
>>> signals but I have no data to back this up! However, given the nature of
>>> linear scales one might do just as well to use linear scale for position
>>> and shaft encoder on the motor for velocity. The system on my Mazak used a
>>> resolver on the servo motor geared (?) 7:1 and 1.6:1 to the ball screw.
>>> Those numbers are from memory and a long time ago i.e a couple of years
>>> before we did the Mazak at Galesburg.
>>>> When I get the machine running with stepper-servos I will probably try
>>> using the R channel for homing.  Thanks for listening. Rant OFF.
>>>> Dave
>>> I have a much simpler setup, the only fully stepper/servo is my sheldon
>>> lathe which is all stepper/servo, or about 1/2 of my 4 axis 6040 mill.
>>> I have motors and drivers to do the same for my ball screw converted
>>> go704. configurable as 3 or 4 axis.  Home is the closing of the $2
>>> switch on each axis.  The 6040 is the odd man out, There, z & b are
>>> stepper/servo's where xy are just steppers. I can have a 1 second power
>>> failure in the middle of a threading operation, remove the tool, rehome
>>> the machine, I have notches in my r8's to replace the lack of tooing
>>> keys go thru the rehome, replace the tool and hit r, all in the middle
>>> of a 50 tpi threading opertion.  That is plenty accurate enough for the
>>> girls I might go with. The only none hard switch is the inductive home
>>> switches on the 4th axis for z & a or b.   My biggest problem is the.3mm
>>> back lash in g7O4 z if the gibs are too tight. & I forget to oil it.
>>>>> On Apr 18, 2026, at 10:49 PM, andrew beck <and...@gm...>
>>> wrote:
>>>>> hey guys
>>>>>
>>>>> just reporting back here with my success with the dual feedback
>>>>>
>>>>> i have 0.1mm backlash still in the ballscrew or somewhere
>>>>>
>>>>> and i have a magnetic scale on the machine also
>>>>>
>>>>> with a encoder on the end of the ballscrew
>>>>>
>>>>> i copied the examples on online of how they did that massive mill and
>>> its
>>>>> working awesome
>>>>>
>>>>> the mill rapids down or feeds down to 0.02 to 0.05 and then the I value
>>>>> from the second PID takes over and moves the last tiny bit
>>>>>
>>>>> which takes a second or so
>>>>>
>>>>> and it stops right where it should everytime within 0.01mm  the scale
>>> says
>>>>> it's perfect to 0.003 on the screen.  and no dithering
>>>>>
>>>>> next issue thought is homing with index
>>>>>
>>>>> either to the motor encoder or scale z pulse
>>>>>
>>>>>
>>>>>
>>>>> i have my x and y axis homing perfectly with encoder index
>>>>>
>>>>> but i can't get linuxcnc to home this z axis to index.  homing without
>>>>> index works fine though.
>>>>>
>>>>> i think it is because linuxcnc internals throws a hissy fit because i
>>> have
>>>>> a hacked up PID system with two forms of feedback getting summed
>>> together
>>>>> any ideas would be great
>>>>>
>>>>> cheers
>>>>>
>>>>> Andrew
>>>>>
>>>>> On Mon, Jan 5, 2026 at 11:04 AM gene heskett <ghe...@sh...>
>>> wrote:
>>>>>> On 1/4/26 01:36, gene heskett wrote:
>>>>>>> On 1/4/26 00:23, andrew beck wrote:
>>>>>>>> hey stuart
>>>>>>>>
>>>>>>>> yeah the ballscrew is connected both ends.  i think one end has the
>>> big
>>>>>>>> angular contact bearings etc
>>>>>>>>
>>>>>>>> and the other only has deep groove ends probably (its much smaller
>>>>>>>> than the
>>>>>>>> driving end)
>>>>>>>>
>>>>>>>> on my other two cnc mills they have angular contact bearings both
>>>>>>>> ends and
>>>>>>>> the screws are stretched between them slightly with a tiny bit of
>>>>>>>> preload
>>>>>>>>
>>>>>> Probably should clarify here. The tension isn't meant to stretch the
>>> screw,
>>>>>> but to pull it tight enough there's no lengthwise backlash under
>>> normal
>>>>>> working loads despite a few microns of wear.  On my sheldon, the z
>>> screw
>>>>>> has only a sliding ball bearing on the right end, so the double
>>> bearing on
>>>>>> the left controls the end play.  After a decade of light use, I'm
>>> still
>>>>>> under 2
>>>>>> thou of play acc a .0001 dial.
I think I'm the lucky amature, which I am.  Now I'm 91, and mainly doing 
my own things, which I cannot show you, JK won't allow it on machines 
that didn't cost an arm & a couple legs.  But I'm still having fun.  
Flowers to all that have helped me for the last 25+ years as you taught 
me about LinuxCNC.
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>>>>>>>> hey guys
>>>>>>>>
>>>>>>>> i was reading the link that sam sent two and it looks like the two
>>> Pid
>>>>>>>> loops are running side by side  and then the outputs are added
>>> together
>>>>>>>> before going to the servo drive
>>>>>>>>
>>>>>>>> would i be correct in thinking that they are using the "sum"
>>>>>>>> component in
>>>>>>>> linuxcnc to do that?
>>>>>>>>
>>>>>>>> if so this is getting pretty simple
>>>>>>>>
>>>>>>>> cheers
>>>>>>>>
>>>>>>>> andrew
>>>>>>>>
>>>>>>>> On Fri, Jan 2, 2026 at 3:07 PM Stuart Stevenson <st...@gm...>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> HI,
>>>>>>>>>    I don't think the LinuxCNC control scheme is cascaded or nested.
>>> I
>>>>>>>>> would
>>>>>>>>> call it parallel.
>>>>>>>>>
>>>>>>>>>    The only backlash problem I can imagine is if the backlash
>>> causes the
>>>>>>>>> motor to dither trying to maintain position because cutting forces
>>>>>>>>> move the
>>>>>>>>> axis enough to cause the control to try to correct the axis
>>> position.
>>>>>>>>>    Is the ball screw supported on each end? If it is, then, is it
>>>>>>>>> possible
>>>>>>>>> the screw has some stretch preload.
>>>>>>>>>
>>>>>>>>> regards
>>>>>>>>> Stuart
>>>>>>>>>
>>>>>>>>> On Thu, Jan 1, 2026 at 4:10 PM andrew beck <
>>> and...@gm...>
>>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>>> hey guys
>>>>>>>>>> sam i just looked at that link you sent
>>>>>>>>>>
>>>>>>>>>> that looks pretty cool
>>>>>>>>>>
>>>>>>>>>> only thing is i don't know is if it will work to reduce the
>>> backlash
>>>>>>>>> issue
>>>>>>>>>> i am getting.  I have about 0.10mm of backlash on each axis
>>> half of
>>>>>>>>> that
>>>>>>>>>> is from the thrust bearings which is fixable with new bearings
>>>>>>>>>> the rest is from the ball nut i think and i am not willing to fix
>>> that
>>>>>>> Those tiny ball screws stuart sold me 25 years ago were just a hair
>>>>>>> sloppy.
>>>>>>> I found the balls .001 bigger on ebay and restuffed the nuts. One of
>>> them
>>>>>>> is in the Y of my sheldon, and has about a thou of backlash today I
>>> had
>>>>>>> to make a cage for the nut with teeny grub screws to stop the nuts
>>> end-
>>>>>>> play in the cage.  So oversized balls are one possibility. Ticklish
>>>>>>> work tho.
>>>>>>>>>> but i can only try it.
>>>>>>>>>>
>>>>>>>>>> does anyone want to have a go with making a config like they
>>> did?  one
>>>>>>>>> axis
>>>>>>>>>> would be best  I am struggling to get my head around the different
>>>>>>>>> layers.
>>>>>>>>>> i probably need to write it all out or use a diagram or something.
>>>>>>>>>>
>>>>>>>>>> regardless i am sure i will work it out.  just might take some
>>> brain
>>>>>>>>> cells
>>>>>>>>>> cheers
>>>>>>>>>>
>>>>>>>>>> Andrew
>>>>>>>>>>
>>>>>>>>>> On Fri, Jan 2, 2026 at 4:54 AM Sam Sokolik <sam...@gm...>
>>>>>> wrote:
>>>>>>>>>>> This was also John k..  I would trust his solution.  He is the
>>> one
>>>>>>>>>>> that
>>>>>>>>>>> came up with hal in linuxcnc... (Among other things).
>>>>>>>>>>>
>>>>>>>>>>> On Thu, Jan 1, 2026, 9:49 AM andy pugh <bod...@gm...>
>>> wrote:
>>>>>>>>>>>> On Thu, 1 Jan 2026 at 15:41, andy pugh <bod...@gm...>
>>> wrote:
>>>>>>>>>>>>> On Wed, 31 Dec 2025 at 22:14, andrew beck <
>>>>>>>>> and...@gm...>
>>>>>>>>>>>> wrote:
>>>>>>>>>>>>>> just looking for a config example if possible for a mesa card
>>>>>>>>> from
>>>>>>>>>>>> someone
>>>>>>>>>>>>>> that has this nested PID loop setup.
>>>>>>>>>>>>> This may not be as effective as you would hope. Cascaded PID
>>>>>>>>> loops...
>>>>>>>>>>>> Actually, what was done with the MPM jigmill wasn't a cascaded
>>> PID.
>>>>>>>>>>>> What was done there was to run a P + FF control based on the
>>> motor
>>>>>>>>>>>> encoder and an I control based on the linear scales.
>>>>>>>>>>>>
>>>>>>>>>>>> Then the two controllers were summed together to create a PID
>>>>>>>>>>>> controller, but with I using a different feedback source than P
>>> and
>>>>>>>>> D.
>>>>>>>>>>>> --
>>>>>>>>>>>> atp
>>>>>>>>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is
>>>>>>>>>>>> designed for the especial use of mechanical geniuses,
>>> daredevils and
>>>>>>>>>>>> lunatics."
>>>>>>>>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> Emc-users mailing list
>>>>>>>>>>>> Emc...@li...
>>>>>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>>>>>>>
>>>>>> Cheers, Gene Heskett, CET.
>>>>>> --
>>>>>> "There are four boxes to be used in defense of liberty:
>>>>>>    soap, ballot, jury, and ammo. Please use in that order."
>>>>>> -Ed Howdershelt (Author, 1940)
>>>>>> If we desire respect for the law, we must first make the law
>>> respectable.
>>>>>>    - Louis D. Brandeis
>>>>>> Don't poison our oceans, interdict drugs at the src.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Emc-users mailing list
>>>>>> Emc...@li...
>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>
>>>>> _______________________________________________
>>>>> Emc-users mailing list
>>>>> Emc...@li...
>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>
>>>> _______________________________________________
>>>> Emc-users mailing list
>>>> Emc...@li...
>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>> Cheers, Gene Heskett, CET.
>>> --
>>> "There are four boxes to be used in defense of liberty:
>>>    soap, ballot, jury, and ammo. Please use in that order."
>>> -Ed Howdershelt (Author, 1940)
>>> If we desire respect for the law, we must first make the law respectable.
>>>    - Louis D. Brandeis
>>> Don't poison our oceans, interdict drugs at the src.
>>>
>>>
>>>
>>> _______________________________________________
>>> Emc-users mailing list
>>> Emc...@li...
>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Cheers, Gene Heskett, CET.
-- 
"There are four boxes to be used in defense of liberty:
  soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
  - Louis D. Brandeis
Don't poison our oceans, interdict drugs at the src.

Re: [Emc-users] setting up dual PID loops for servoencodersandscales

[andrew b. <and...@gm...>]

hey guys

finally made a thread on the forum

lots of photos and this youtube video

for those that are interested

cheers

https://youtu.be/AmQGh_Cwff0?si=ZIihICf10Gto2px7



https://forum.linuxcnc.org/show-your-stuff/58689-large-fil-cnc-machine-retrofit-12-ton-larger-maching-running-linuxcnc#345849



andrew

On Thu, Apr 23, 2026 at 7:37 AM andrew beck <and...@gm...>
wrote:

> Hey guys
> thanks for the replies
>
> the homing is a interesting issue
>
> I had a bit of a play and made a copy of my config that i hacked.
>
> What i found was that if i combined my original 2 PID loops into 1 loop
> and used the scale for position and used the motor velocity on encoder for
> velocity all in one PID then homing to index enable worked perfectly.
>
> but doing it that way the motor tuning was not as good.  backlash is a
> constant of 0.1mm and the motor just jumped across that backlash whenever
> it moved.  in practice that meant that the absolute scale position hovered
> by +-0.01 or so.
>
> this was not bad and totally usable.  If i had done this option first i
> would have called it good and just used it.  but the movement was much
> louder and less smooth than the two PID loops which get run through a sum
> component.  As the original two PID loops was much much smoother, it was
> perfect and once i come to a stop the drive rapids to within 0.01 or 0.02
> and then creeps the last 0.02mm (using the integral value which takes about
> a second)  and ends up in the right place within 0.005mm or less.
> basically perfect every time with no dithering.
>
> It is now my most accurate machine.  and really nice
>
> also the homing when homing I home all axis at the same time.  X and Y get
> homed to index enable like normal.
>
> and the Z value i trick the home switch by checking the joint state.  How
> this works is the Joint2 switch state goes form 7 when searching for switch
> the first time to 12 when latching on to switch slowly the second time
>
> so in classic ladder i set up two compare functions that basically choose
> whether to listen to the main home switch or the z axis motor encoder Z
> index pulse.  (this is different to the index enable pulse and this is
> possible to miss when only checking in software not hardware.  but at a
> slow speed i haven't found any issues yet, and when testing with a dial
> indicator i can't see any changes between homing.  I can rehome linuxcnc up
> the top of the travel beside the home switch and then rapid down to the
> table which is about 1m away and the dial indicator is definitely within
> 0.01 each time.  i can't really see any movement on it.
>
> So pretty happy all in all would like to fix the index enable issue in the
> future but for now it's working fine.
>
> this is a 40 year old machine and weighs 12 ton.  and when i got it the
> backlash was 0.40mm.  I replaced all the thrust bearings and changed from
> reduction gearbox to a nice mazak flexible coupling and direct drive.  The
> timing belt was T8 timing belt so not even HTD profile which has more
> backlash which didn't help.  The FIL factory actually got the location of
> the Z axis 2nd ballscrew mount out by 2.4mm which i was shocked by.  i
> double checked measuring against the slideways at the top and bottom of the
> screw and yeah it was out 2.4mm from factory!  so that is why all the
> thrust bearings were stuffed.
>
> anyway just about to get it running into production.  this machine will be
> running like 16 hrs a day shortly probably.
>
> cheers
>
> Andrew
>
>
> On Thu, 23 Apr 2026, 5:11 am gene heskett, <ghe...@sh...> wrote:
>
>> On 4/22/26 10:44, Dave Engvall wrote:
>> > Hi Andrew et al
>> >
>> > I have a cinci contourmaster set up with US made glass scales and a
>> rotary encoder on the ballscrew. I’m in transition to stepper-servos but
>> progressing slowly.
>> > When I started this process I did a manual check with the hand crank vs
>> the X axis scale. Proceeding in the positive direction I manually moved in
>> 1” increments, ie 4 turns of the hand wheel. Even in this early 1960’s
>> machine the glass scale was dead on. Since I’m protective of the US scale I
>> removed it and installed a Chinese scale.
>> > Both scales have a reference channel spaced with markers 50 mm apart I
>> suspect the US made scale has guard ticks either side of the reference
>> mark. I know the Chinese one's do.
>> > Homing procedure was simple. I installed a laser diode and a tab with a
>> hole in it at the end of the axis and manually homed to that before kicking
>> off a home of the machine. Z was done by manually moving Z to the upper
>> stop. If I positioned the tab and or Z stop correctly it never had to move
>> more than ~ 3 mm to index. All of this used the normal homing procedure.
>> Scan past the index and capture the position of index then move as
>> necessary to home. It is my impression that homing should be done in that
>> manner and not dual channel but after homing position seeking uses both
>> signals but I have no data to back this up! However, given the nature of
>> linear scales one might do just as well to use linear scale for position
>> and shaft encoder on the motor for velocity. The system on my Mazak used a
>> resolver on the servo motor geared (?) 7:1 and 1.6:1 to the ball screw.
>> Those numbers are from memory and a long time ago i.e a couple of years
>> before we did the Mazak at Galesburg.
>> > When I get the machine running with stepper-servos I will probably try
>> using the R channel for homing.  Thanks for listening. Rant OFF.
>> >
>> > Dave
>> I have a much simpler setup, the only fully stepper/servo is my sheldon
>> lathe which is all stepper/servo, or about 1/2 of my 4 axis 6040 mill.
>> I have motors and drivers to do the same for my ball screw converted
>> go704. configurable as 3 or 4 axis.  Home is the closing of the $2
>> switch on each axis.  The 6040 is the odd man out, There, z & b are
>> stepper/servo's where xy are just steppers. I can have a 1 second power
>> failure in the middle of a threading operation, remove the tool, rehome
>> the machine, I have notches in my r8's to replace the lack of tooing
>> keys go thru the rehome, replace the tool and hit r, all in the middle
>> of a 50 tpi threading opertion.  That is plenty accurate enough for the
>> girls I might go with. The only none hard switch is the inductive home
>> switches on the 4th axis for z & a or b.   My biggest problem is the.3mm
>> back lash in g7O4 z if the gibs are too tight. & I forget to oil it.
>> >> On Apr 18, 2026, at 10:49 PM, andrew beck <and...@gm...>
>> wrote:
>> >>
>> >> hey guys
>> >>
>> >> just reporting back here with my success with the dual feedback
>> >>
>> >> i have 0.1mm backlash still in the ballscrew or somewhere
>> >>
>> >> and i have a magnetic scale on the machine also
>> >>
>> >> with a encoder on the end of the ballscrew
>> >>
>> >> i copied the examples on online of how they did that massive mill and
>> its
>> >> working awesome
>> >>
>> >> the mill rapids down or feeds down to 0.02 to 0.05 and then the I value
>> >> from the second PID takes over and moves the last tiny bit
>> >>
>> >> which takes a second or so
>> >>
>> >> and it stops right where it should everytime within 0.01mm  the scale
>> says
>> >> it's perfect to 0.003 on the screen.  and no dithering
>> >>
>> >> next issue thought is homing with index
>> >>
>> >> either to the motor encoder or scale z pulse
>> >>
>> >>
>> >>
>> >> i have my x and y axis homing perfectly with encoder index
>> >>
>> >> but i can't get linuxcnc to home this z axis to index.  homing without
>> >> index works fine though.
>> >>
>> >> i think it is because linuxcnc internals throws a hissy fit because i
>> have
>> >> a hacked up PID system with two forms of feedback getting summed
>> together
>> >>
>> >> any ideas would be great
>> >>
>> >> cheers
>> >>
>> >> Andrew
>> >>
>> >> On Mon, Jan 5, 2026 at 11:04 AM gene heskett <ghe...@sh...>
>> wrote:
>> >>
>> >>> On 1/4/26 01:36, gene heskett wrote:
>> >>>> On 1/4/26 00:23, andrew beck wrote:
>> >>>>> hey stuart
>> >>>>>
>> >>>>> yeah the ballscrew is connected both ends.  i think one end has the
>> big
>> >>>>> angular contact bearings etc
>> >>>>>
>> >>>>> and the other only has deep groove ends probably (its much smaller
>> >>>>> than the
>> >>>>> driving end)
>> >>>>>
>> >>>>> on my other two cnc mills they have angular contact bearings both
>> >>>>> ends and
>> >>>>> the screws are stretched between them slightly with a tiny bit of
>> >>>>> preload
>> >>>>>
>> >>> Probably should clarify here. The tension isn't meant to stretch the
>> screw,
>> >>> but to pull it tight enough there's no lengthwise backlash under
>> normal
>> >>> working loads despite a few microns of wear.  On my sheldon, the z
>> screw
>> >>> has only a sliding ball bearing on the right end, so the double
>> bearing on
>> >>> the left controls the end play.  After a decade of light use, I'm
>> still
>> >>> under 2
>> >>> thou of play acc a .0001 dial.
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
>> >>>
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>> >>>>> hey guys
>> >>>>>
>> >>>>> i was reading the link that sam sent two and it looks like the two
>> Pid
>> >>>>> loops are running side by side  and then the outputs are added
>> together
>> >>>>> before going to the servo drive
>> >>>>>
>> >>>>> would i be correct in thinking that they are using the "sum"
>> >>>>> component in
>> >>>>> linuxcnc to do that?
>> >>>>>
>> >>>>> if so this is getting pretty simple
>> >>>>>
>> >>>>> cheers
>> >>>>>
>> >>>>> andrew
>> >>>>>
>> >>>>> On Fri, Jan 2, 2026 at 3:07 PM Stuart Stevenson <st...@gm...>
>> >>>>> wrote:
>> >>>>>
>> >>>>>> HI,
>> >>>>>>   I don't think the LinuxCNC control scheme is cascaded or nested.
>> I
>> >>>>>> would
>> >>>>>> call it parallel.
>> >>>>>>
>> >>>>>>   The only backlash problem I can imagine is if the backlash
>> causes the
>> >>>>>> motor to dither trying to maintain position because cutting forces
>> >>>>>> move the
>> >>>>>> axis enough to cause the control to try to correct the axis
>> position.
>> >>>>>>
>> >>>>>>   Is the ball screw supported on each end? If it is, then, is it
>> >>>>>> possible
>> >>>>>> the screw has some stretch preload.
>> >>>>>>
>> >>>>>> regards
>> >>>>>> Stuart
>> >>>>>>
>> >>>>>> On Thu, Jan 1, 2026 at 4:10 PM andrew beck <
>> and...@gm...>
>> >>>>>> wrote:
>> >>>>>>
>> >>>>>>> hey guys
>> >>>>>>> sam i just looked at that link you sent
>> >>>>>>>
>> >>>>>>> that looks pretty cool
>> >>>>>>>
>> >>>>>>> only thing is i don't know is if it will work to reduce the
>> backlash
>> >>>>>> issue
>> >>>>>>> i am getting.  I have about 0.10mm of backlash on each axis.
>> half of
>> >>>>>> that
>> >>>>>>> is from the thrust bearings which is fixable with new bearings
>> >>>>>>> the rest is from the ball nut i think and i am not willing to fix
>> that
>> >>>> Those tiny ball screws stuart sold me 25 years ago were just a hair
>> >>>> sloppy.
>> >>>> I found the balls .001 bigger on ebay and restuffed the nuts. One of
>> them
>> >>>> is in the Y of my sheldon, and has about a thou of backlash today I
>> had
>> >>>> to make a cage for the nut with teeny grub screws to stop the nuts
>> end-
>> >>>> play in the cage.  So oversized balls are one possibility. Ticklish
>> >>>> work tho.
>> >>>>>>> but i can only try it.
>> >>>>>>>
>> >>>>>>> does anyone want to have a go with making a config like they
>> did?  one
>> >>>>>> axis
>> >>>>>>> would be best  I am struggling to get my head around the different
>> >>>>>> layers.
>> >>>>>>> i probably need to write it all out or use a diagram or something.
>> >>>>>>>
>> >>>>>>> regardless i am sure i will work it out.  just might take some
>> brain
>> >>>>>> cells
>> >>>>>>>
>> >>>>>>> cheers
>> >>>>>>>
>> >>>>>>> Andrew
>> >>>>>>>
>> >>>>>>> On Fri, Jan 2, 2026 at 4:54 AM Sam Sokolik <sam...@gm...>
>> >>> wrote:
>> >>>>>>>> This was also John k..  I would trust his solution.  He is the
>> one
>> >>>>>>>> that
>> >>>>>>>> came up with hal in linuxcnc... (Among other things).
>> >>>>>>>>
>> >>>>>>>> On Thu, Jan 1, 2026, 9:49 AM andy pugh <bod...@gm...>
>> wrote:
>> >>>>>>>>
>> >>>>>>>>> On Thu, 1 Jan 2026 at 15:41, andy pugh <bod...@gm...>
>> wrote:
>> >>>>>>>>>> On Wed, 31 Dec 2025 at 22:14, andrew beck <
>> >>>>>> and...@gm...>
>> >>>>>>>>> wrote:
>> >>>>>>>>>>> just looking for a config example if possible for a mesa card
>> >>>>>> from
>> >>>>>>>>> someone
>> >>>>>>>>>>> that has this nested PID loop setup.
>> >>>>>>>>>> This may not be as effective as you would hope. Cascaded PID
>> >>>>>> loops...
>> >>>>>>>>> Actually, what was done with the MPM jigmill wasn't a cascaded
>> PID.
>> >>>>>>>>> What was done there was to run a P + FF control based on the
>> motor
>> >>>>>>>>> encoder and an I control based on the linear scales.
>> >>>>>>>>>
>> >>>>>>>>> Then the two controllers were summed together to create a PID
>> >>>>>>>>> controller, but with I using a different feedback source than P
>> and
>> >>>>>> D.
>> >>>>>>>>> --
>> >>>>>>>>> atp
>> >>>>>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is
>> >>>>>>>>> designed for the especial use of mechanical geniuses,
>> daredevils and
>> >>>>>>>>> lunatics."
>> >>>>>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912
>> >>>>>>>>>
>> >>>>>>>>>
>> >>>>>>>>> _______________________________________________
>> >>>>>>>>> Emc-users mailing list
>> >>>>>>>>> Emc...@li...
>> >>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>> >>>>>>>>>
>> >>> Cheers, Gene Heskett, CET.
>> >>> --
>> >>> "There are four boxes to be used in defense of liberty:
>> >>>   soap, ballot, jury, and ammo. Please use in that order."
>> >>> -Ed Howdershelt (Author, 1940)
>> >>> If we desire respect for the law, we must first make the law
>> respectable.
>> >>>   - Louis D. Brandeis
>> >>> Don't poison our oceans, interdict drugs at the src.
>> >>>
>> >>>
>> >>>
>> >>>
>> >>> _______________________________________________
>> >>> Emc-users mailing list
>> >>> Emc...@li...
>> >>> https://lists.sourceforge.net/lists/listinfo/emc-users
>> >>>
>> >> _______________________________________________
>> >> Emc-users mailing list
>> >> Emc...@li...
>> >> https://lists.sourceforge.net/lists/listinfo/emc-users
>> >
>> >
>> > _______________________________________________
>> > Emc-users mailing list
>> > Emc...@li...
>> > https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>> Cheers, Gene Heskett, CET.
>> --
>> "There are four boxes to be used in defense of liberty:
>>   soap, ballot, jury, and ammo. Please use in that order."
>> -Ed Howdershelt (Author, 1940)
>> If we desire respect for the law, we must first make the law respectable.
>>   - Louis D. Brandeis
>> Don't poison our oceans, interdict drugs at the src.
>>
>>
>>
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li...
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>

Re: [Emc-users] setting up dual PID loops for servoencodersandscales

[andrew b. <and...@gm...>]

Hey guys
thanks for the replies

the homing is a interesting issue

I had a bit of a play and made a copy of my config that i hacked.

What i found was that if i combined my original 2 PID loops into 1 loop and
used the scale for position and used the motor velocity on encoder for
velocity all in one PID then homing to index enable worked perfectly.

but doing it that way the motor tuning was not as good.  backlash is a
constant of 0.1mm and the motor just jumped across that backlash whenever
it moved.  in practice that meant that the absolute scale position hovered
by +-0.01 or so.

this was not bad and totally usable.  If i had done this option first i
would have called it good and just used it.  but the movement was much
louder and less smooth than the two PID loops which get run through a sum
component.  As the original two PID loops was much much smoother, it was
perfect and once i come to a stop the drive rapids to within 0.01 or 0.02
and then creeps the last 0.02mm (using the integral value which takes about
a second)  and ends up in the right place within 0.005mm or less.
basically perfect every time with no dithering.

It is now my most accurate machine.  and really nice

also the homing when homing I home all axis at the same time.  X and Y get
homed to index enable like normal.

and the Z value i trick the home switch by checking the joint state.  How
this works is the Joint2 switch state goes form 7 when searching for switch
the first time to 12 when latching on to switch slowly the second time

so in classic ladder i set up two compare functions that basically choose
whether to listen to the main home switch or the z axis motor encoder Z
index pulse.  (this is different to the index enable pulse and this is
possible to miss when only checking in software not hardware.  but at a
slow speed i haven't found any issues yet, and when testing with a dial
indicator i can't see any changes between homing.  I can rehome linuxcnc up
the top of the travel beside the home switch and then rapid down to the
table which is about 1m away and the dial indicator is definitely within
0.01 each time.  i can't really see any movement on it.

So pretty happy all in all would like to fix the index enable issue in the
future but for now it's working fine.

this is a 40 year old machine and weighs 12 ton.  and when i got it the
backlash was 0.40mm.  I replaced all the thrust bearings and changed from
reduction gearbox to a nice mazak flexible coupling and direct drive.  The
timing belt was T8 timing belt so not even HTD profile which has more
backlash which didn't help.  The FIL factory actually got the location of
the Z axis 2nd ballscrew mount out by 2.4mm which i was shocked by.  i
double checked measuring against the slideways at the top and bottom of the
screw and yeah it was out 2.4mm from factory!  so that is why all the
thrust bearings were stuffed.

anyway just about to get it running into production.  this machine will be
running like 16 hrs a day shortly probably.

cheers

Andrew


On Thu, 23 Apr 2026, 5:11 am gene heskett, <ghe...@sh...> wrote:

> On 4/22/26 10:44, Dave Engvall wrote:
> > Hi Andrew et al
> >
> > I have a cinci contourmaster set up with US made glass scales and a
> rotary encoder on the ballscrew. I’m in transition to stepper-servos but
> progressing slowly.
> > When I started this process I did a manual check with the hand crank vs
> the X axis scale. Proceeding in the positive direction I manually moved in
> 1” increments, ie 4 turns of the hand wheel. Even in this early 1960’s
> machine the glass scale was dead on. Since I’m protective of the US scale I
> removed it and installed a Chinese scale.
> > Both scales have a reference channel spaced with markers 50 mm apart I
> suspect the US made scale has guard ticks either side of the reference
> mark. I know the Chinese one's do.
> > Homing procedure was simple. I installed a laser diode and a tab with a
> hole in it at the end of the axis and manually homed to that before kicking
> off a home of the machine. Z was done by manually moving Z to the upper
> stop. If I positioned the tab and or Z stop correctly it never had to move
> more than ~ 3 mm to index. All of this used the normal homing procedure.
> Scan past the index and capture the position of index then move as
> necessary to home. It is my impression that homing should be done in that
> manner and not dual channel but after homing position seeking uses both
> signals but I have no data to back this up! However, given the nature of
> linear scales one might do just as well to use linear scale for position
> and shaft encoder on the motor for velocity. The system on my Mazak used a
> resolver on the servo motor geared (?) 7:1 and 1.6:1 to the ball screw.
> Those numbers are from memory and a long time ago i.e a couple of years
> before we did the Mazak at Galesburg.
> > When I get the machine running with stepper-servos I will probably try
> using the R channel for homing.  Thanks for listening. Rant OFF.
> >
> > Dave
> I have a much simpler setup, the only fully stepper/servo is my sheldon
> lathe which is all stepper/servo, or about 1/2 of my 4 axis 6040 mill.
> I have motors and drivers to do the same for my ball screw converted
> go704. configurable as 3 or 4 axis.  Home is the closing of the $2
> switch on each axis.  The 6040 is the odd man out, There, z & b are
> stepper/servo's where xy are just steppers. I can have a 1 second power
> failure in the middle of a threading operation, remove the tool, rehome
> the machine, I have notches in my r8's to replace the lack of tooing
> keys go thru the rehome, replace the tool and hit r, all in the middle
> of a 50 tpi threading opertion.  That is plenty accurate enough for the
> girls I might go with. The only none hard switch is the inductive home
> switches on the 4th axis for z & a or b.   My biggest problem is the.3mm
> back lash in g7O4 z if the gibs are too tight. & I forget to oil it.
> >> On Apr 18, 2026, at 10:49 PM, andrew beck <and...@gm...>
> wrote:
> >>
> >> hey guys
> >>
> >> just reporting back here with my success with the dual feedback
> >>
> >> i have 0.1mm backlash still in the ballscrew or somewhere
> >>
> >> and i have a magnetic scale on the machine also
> >>
> >> with a encoder on the end of the ballscrew
> >>
> >> i copied the examples on online of how they did that massive mill and
> its
> >> working awesome
> >>
> >> the mill rapids down or feeds down to 0.02 to 0.05 and then the I value
> >> from the second PID takes over and moves the last tiny bit
> >>
> >> which takes a second or so
> >>
> >> and it stops right where it should everytime within 0.01mm  the scale
> says
> >> it's perfect to 0.003 on the screen.  and no dithering
> >>
> >> next issue thought is homing with index
> >>
> >> either to the motor encoder or scale z pulse
> >>
> >>
> >>
> >> i have my x and y axis homing perfectly with encoder index
> >>
> >> but i can't get linuxcnc to home this z axis to index.  homing without
> >> index works fine though.
> >>
> >> i think it is because linuxcnc internals throws a hissy fit because i
> have
> >> a hacked up PID system with two forms of feedback getting summed
> together
> >>
> >> any ideas would be great
> >>
> >> cheers
> >>
> >> Andrew
> >>
> >> On Mon, Jan 5, 2026 at 11:04 AM gene heskett <ghe...@sh...>
> wrote:
> >>
> >>> On 1/4/26 01:36, gene heskett wrote:
> >>>> On 1/4/26 00:23, andrew beck wrote:
> >>>>> hey stuart
> >>>>>
> >>>>> yeah the ballscrew is connected both ends.  i think one end has the
> big
> >>>>> angular contact bearings etc
> >>>>>
> >>>>> and the other only has deep groove ends probably (its much smaller
> >>>>> than the
> >>>>> driving end)
> >>>>>
> >>>>> on my other two cnc mills they have angular contact bearings both
> >>>>> ends and
> >>>>> the screws are stretched between them slightly with a tiny bit of
> >>>>> preload
> >>>>>
> >>> Probably should clarify here. The tension isn't meant to stretch the
> screw,
> >>> but to pull it tight enough there's no lengthwise backlash under normal
> >>> working loads despite a few microns of wear.  On my sheldon, the z
> screw
> >>> has only a sliding ball bearing on the right end, so the double
> bearing on
> >>> the left controls the end play.  After a decade of light use, I'm still
> >>> under 2
> >>> thou of play acc a .0001 dial.
> >>>
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> >>>
> >>>>> hey guys
> >>>>>
> >>>>> i was reading the link that sam sent two and it looks like the two
> Pid
> >>>>> loops are running side by side  and then the outputs are added
> together
> >>>>> before going to the servo drive
> >>>>>
> >>>>> would i be correct in thinking that they are using the "sum"
> >>>>> component in
> >>>>> linuxcnc to do that?
> >>>>>
> >>>>> if so this is getting pretty simple
> >>>>>
> >>>>> cheers
> >>>>>
> >>>>> andrew
> >>>>>
> >>>>> On Fri, Jan 2, 2026 at 3:07 PM Stuart Stevenson <st...@gm...>
> >>>>> wrote:
> >>>>>
> >>>>>> HI,
> >>>>>>   I don't think the LinuxCNC control scheme is cascaded or nested. I
> >>>>>> would
> >>>>>> call it parallel.
> >>>>>>
> >>>>>>   The only backlash problem I can imagine is if the backlash causes
> the
> >>>>>> motor to dither trying to maintain position because cutting forces
> >>>>>> move the
> >>>>>> axis enough to cause the control to try to correct the axis
> position.
> >>>>>>
> >>>>>>   Is the ball screw supported on each end? If it is, then, is it
> >>>>>> possible
> >>>>>> the screw has some stretch preload.
> >>>>>>
> >>>>>> regards
> >>>>>> Stuart
> >>>>>>
> >>>>>> On Thu, Jan 1, 2026 at 4:10 PM andrew beck <
> and...@gm...>
> >>>>>> wrote:
> >>>>>>
> >>>>>>> hey guys
> >>>>>>> sam i just looked at that link you sent
> >>>>>>>
> >>>>>>> that looks pretty cool
> >>>>>>>
> >>>>>>> only thing is i don't know is if it will work to reduce the
> backlash
> >>>>>> issue
> >>>>>>> i am getting.  I have about 0.10mm of backlash on each axis.  half
> of
> >>>>>> that
> >>>>>>> is from the thrust bearings which is fixable with new bearings
> >>>>>>> the rest is from the ball nut i think and i am not willing to fix
> that
> >>>> Those tiny ball screws stuart sold me 25 years ago were just a hair
> >>>> sloppy.
> >>>> I found the balls .001 bigger on ebay and restuffed the nuts. One of
> them
> >>>> is in the Y of my sheldon, and has about a thou of backlash today I
> had
> >>>> to make a cage for the nut with teeny grub screws to stop the nuts
> end-
> >>>> play in the cage.  So oversized balls are one possibility. Ticklish
> >>>> work tho.
> >>>>>>> but i can only try it.
> >>>>>>>
> >>>>>>> does anyone want to have a go with making a config like they did?
> one
> >>>>>> axis
> >>>>>>> would be best  I am struggling to get my head around the different
> >>>>>> layers.
> >>>>>>> i probably need to write it all out or use a diagram or something.
> >>>>>>>
> >>>>>>> regardless i am sure i will work it out.  just might take some
> brain
> >>>>>> cells
> >>>>>>>
> >>>>>>> cheers
> >>>>>>>
> >>>>>>> Andrew
> >>>>>>>
> >>>>>>> On Fri, Jan 2, 2026 at 4:54 AM Sam Sokolik <sam...@gm...>
> >>> wrote:
> >>>>>>>> This was also John k..  I would trust his solution.  He is the one
> >>>>>>>> that
> >>>>>>>> came up with hal in linuxcnc... (Among other things).
> >>>>>>>>
> >>>>>>>> On Thu, Jan 1, 2026, 9:49 AM andy pugh <bod...@gm...>
> wrote:
> >>>>>>>>
> >>>>>>>>> On Thu, 1 Jan 2026 at 15:41, andy pugh <bod...@gm...>
> wrote:
> >>>>>>>>>> On Wed, 31 Dec 2025 at 22:14, andrew beck <
> >>>>>> and...@gm...>
> >>>>>>>>> wrote:
> >>>>>>>>>>> just looking for a config example if possible for a mesa card
> >>>>>> from
> >>>>>>>>> someone
> >>>>>>>>>>> that has this nested PID loop setup.
> >>>>>>>>>> This may not be as effective as you would hope. Cascaded PID
> >>>>>> loops...
> >>>>>>>>> Actually, what was done with the MPM jigmill wasn't a cascaded
> PID.
> >>>>>>>>> What was done there was to run a P + FF control based on the
> motor
> >>>>>>>>> encoder and an I control based on the linear scales.
> >>>>>>>>>
> >>>>>>>>> Then the two controllers were summed together to create a PID
> >>>>>>>>> controller, but with I using a different feedback source than P
> and
> >>>>>> D.
> >>>>>>>>> --
> >>>>>>>>> atp
> >>>>>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is
> >>>>>>>>> designed for the especial use of mechanical geniuses, daredevils
> and
> >>>>>>>>> lunatics."
> >>>>>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912
> >>>>>>>>>
> >>>>>>>>>
> >>>>>>>>> _______________________________________________
> >>>>>>>>> Emc-users mailing list
> >>>>>>>>> Emc...@li...
> >>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>>>>>>>>
> >>> Cheers, Gene Heskett, CET.
> >>> --
> >>> "There are four boxes to be used in defense of liberty:
> >>>   soap, ballot, jury, and ammo. Please use in that order."
> >>> -Ed Howdershelt (Author, 1940)
> >>> If we desire respect for the law, we must first make the law
> respectable.
> >>>   - Louis D. Brandeis
> >>> Don't poison our oceans, interdict drugs at the src.
> >>>
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> Emc-users mailing list
> >>> Emc...@li...
> >>> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>>
> >> _______________________________________________
> >> Emc-users mailing list
> >> Emc...@li...
> >> https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> >
> > _______________________________________________
> > Emc-users mailing list
> > Emc...@li...
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
> Cheers, Gene Heskett, CET.
> --
> "There are four boxes to be used in defense of liberty:
>   soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author, 1940)
> If we desire respect for the law, we must first make the law respectable.
>   - Louis D. Brandeis
> Don't poison our oceans, interdict drugs at the src.
>
>
>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users
>

Re: [Emc-users] setting up dual PID loops for servoencodersandscales

[gene h. <ghe...@sh...>]

On 4/22/26 10:44, Dave Engvall wrote:
> Hi Andrew et al
>
> I have a cinci contourmaster set up with US made glass scales and a rotary encoder on the ballscrew. I’m in transition to stepper-servos but progressing slowly.
> When I started this process I did a manual check with the hand crank vs the X axis scale. Proceeding in the positive direction I manually moved in 1” increments, ie 4 turns of the hand wheel. Even in this early 1960’s machine the glass scale was dead on. Since I’m protective of the US scale I removed it and installed a Chinese scale.
> Both scales have a reference channel spaced with markers 50 mm apart I suspect the US made scale has guard ticks either side of the reference mark. I know the Chinese one's do.
> Homing procedure was simple. I installed a laser diode and a tab with a hole in it at the end of the axis and manually homed to that before kicking off a home of the machine. Z was done by manually moving Z to the upper stop. If I positioned the tab and or Z stop correctly it never had to move more than ~ 3 mm to index. All of this used the normal homing procedure. Scan past the index and capture the position of index then move as necessary to home. It is my impression that homing should be done in that manner and not dual channel but after homing position seeking uses both signals but I have no data to back this up! However, given the nature of linear scales one might do just as well to use linear scale for position and shaft encoder on the motor for velocity. The system on my Mazak used a resolver on the servo motor geared (?) 7:1 and 1.6:1 to the ball screw. Those numbers are from memory and a long time ago i.e a couple of years before we did the Mazak at Galesburg.
> When I get the machine running with stepper-servos I will probably try using the R channel for homing.  Thanks for listening. Rant OFF.
>
> Dave
I have a much simpler setup, the only fully stepper/servo is my sheldon 
lathe which is all stepper/servo, or about 1/2 of my 4 axis 6040 mill.  
I have motors and drivers to do the same for my ball screw converted 
go704. configurable as 3 or 4 axis.  Home is the closing of the $2 
switch on each axis.  The 6040 is the odd man out, There, z & b are 
stepper/servo's where xy are just steppers. I can have a 1 second power 
failure in the middle of a threading operation, remove the tool, rehome 
the machine, I have notches in my r8's to replace the lack of tooing 
keys go thru the rehome, replace the tool and hit r, all in the middle 
of a 50 tpi threading opertion.  That is plenty accurate enough for the 
girls I might go with. The only none hard switch is the inductive home 
switches on the 4th axis for z & a or b.   My biggest problem is the.3mm 
back lash in g7O4 z if the gibs are too tight. & I forget to oil it.
>> On Apr 18, 2026, at 10:49 PM, andrew beck <and...@gm...> wrote:
>>
>> hey guys
>>
>> just reporting back here with my success with the dual feedback
>>
>> i have 0.1mm backlash still in the ballscrew or somewhere
>>
>> and i have a magnetic scale on the machine also
>>
>> with a encoder on the end of the ballscrew
>>
>> i copied the examples on online of how they did that massive mill and its
>> working awesome
>>
>> the mill rapids down or feeds down to 0.02 to 0.05 and then the I value
>> from the second PID takes over and moves the last tiny bit
>>
>> which takes a second or so
>>
>> and it stops right where it should everytime within 0.01mm  the scale says
>> it's perfect to 0.003 on the screen.  and no dithering
>>
>> next issue thought is homing with index
>>
>> either to the motor encoder or scale z pulse
>>
>>
>>
>> i have my x and y axis homing perfectly with encoder index
>>
>> but i can't get linuxcnc to home this z axis to index.  homing without
>> index works fine though.
>>
>> i think it is because linuxcnc internals throws a hissy fit because i have
>> a hacked up PID system with two forms of feedback getting summed together
>>
>> any ideas would be great
>>
>> cheers
>>
>> Andrew
>>
>> On Mon, Jan 5, 2026 at 11:04 AM gene heskett <ghe...@sh...> wrote:
>>
>>> On 1/4/26 01:36, gene heskett wrote:
>>>> On 1/4/26 00:23, andrew beck wrote:
>>>>> hey stuart
>>>>>
>>>>> yeah the ballscrew is connected both ends.  i think one end has the big
>>>>> angular contact bearings etc
>>>>>
>>>>> and the other only has deep groove ends probably (its much smaller
>>>>> than the
>>>>> driving end)
>>>>>
>>>>> on my other two cnc mills they have angular contact bearings both
>>>>> ends and
>>>>> the screws are stretched between them slightly with a tiny bit of
>>>>> preload
>>>>>
>>> Probably should clarify here. The tension isn't meant to stretch the screw,
>>> but to pull it tight enough there's no lengthwise backlash under normal
>>> working loads despite a few microns of wear.  On my sheldon, the z screw
>>> has only a sliding ball bearing on the right end, so the double bearing on
>>> the left controls the end play.  After a decade of light use, I'm still
>>> under 2
>>> thou of play acc a .0001 dial.
>>>
>>>
>>>
>>>
>>>
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>>>>> hey guys
>>>>>
>>>>> i was reading the link that sam sent two and it looks like the two Pid
>>>>> loops are running side by side  and then the outputs are added together
>>>>> before going to the servo drive
>>>>>
>>>>> would i be correct in thinking that they are using the "sum"
>>>>> component in
>>>>> linuxcnc to do that?
>>>>>
>>>>> if so this is getting pretty simple
>>>>>
>>>>> cheers
>>>>>
>>>>> andrew
>>>>>
>>>>> On Fri, Jan 2, 2026 at 3:07 PM Stuart Stevenson <st...@gm...>
>>>>> wrote:
>>>>>
>>>>>> HI,
>>>>>>   I don't think the LinuxCNC control scheme is cascaded or nested. I
>>>>>> would
>>>>>> call it parallel.
>>>>>>
>>>>>>   The only backlash problem I can imagine is if the backlash causes the
>>>>>> motor to dither trying to maintain position because cutting forces
>>>>>> move the
>>>>>> axis enough to cause the control to try to correct the axis position.
>>>>>>
>>>>>>   Is the ball screw supported on each end? If it is, then, is it
>>>>>> possible
>>>>>> the screw has some stretch preload.
>>>>>>
>>>>>> regards
>>>>>> Stuart
>>>>>>
>>>>>> On Thu, Jan 1, 2026 at 4:10 PM andrew beck <and...@gm...>
>>>>>> wrote:
>>>>>>
>>>>>>> hey guys
>>>>>>> sam i just looked at that link you sent
>>>>>>>
>>>>>>> that looks pretty cool
>>>>>>>
>>>>>>> only thing is i don't know is if it will work to reduce the backlash
>>>>>> issue
>>>>>>> i am getting.  I have about 0.10mm of backlash on each axis.  half of
>>>>>> that
>>>>>>> is from the thrust bearings which is fixable with new bearings
>>>>>>> the rest is from the ball nut i think and i am not willing to fix that
>>>> Those tiny ball screws stuart sold me 25 years ago were just a hair
>>>> sloppy.
>>>> I found the balls .001 bigger on ebay and restuffed the nuts. One of them
>>>> is in the Y of my sheldon, and has about a thou of backlash today I had
>>>> to make a cage for the nut with teeny grub screws to stop the nuts end-
>>>> play in the cage.  So oversized balls are one possibility. Ticklish
>>>> work tho.
>>>>>>> but i can only try it.
>>>>>>>
>>>>>>> does anyone want to have a go with making a config like they did?  one
>>>>>> axis
>>>>>>> would be best  I am struggling to get my head around the different
>>>>>> layers.
>>>>>>> i probably need to write it all out or use a diagram or something.
>>>>>>>
>>>>>>> regardless i am sure i will work it out.  just might take some brain
>>>>>> cells
>>>>>>>
>>>>>>> cheers
>>>>>>>
>>>>>>> Andrew
>>>>>>>
>>>>>>> On Fri, Jan 2, 2026 at 4:54 AM Sam Sokolik <sam...@gm...>
>>> wrote:
>>>>>>>> This was also John k..  I would trust his solution.  He is the one
>>>>>>>> that
>>>>>>>> came up with hal in linuxcnc... (Among other things).
>>>>>>>>
>>>>>>>> On Thu, Jan 1, 2026, 9:49 AM andy pugh <bod...@gm...> wrote:
>>>>>>>>
>>>>>>>>> On Thu, 1 Jan 2026 at 15:41, andy pugh <bod...@gm...> wrote:
>>>>>>>>>> On Wed, 31 Dec 2025 at 22:14, andrew beck <
>>>>>> and...@gm...>
>>>>>>>>> wrote:
>>>>>>>>>>> just looking for a config example if possible for a mesa card
>>>>>> from
>>>>>>>>> someone
>>>>>>>>>>> that has this nested PID loop setup.
>>>>>>>>>> This may not be as effective as you would hope. Cascaded PID
>>>>>> loops...
>>>>>>>>> Actually, what was done with the MPM jigmill wasn't a cascaded PID.
>>>>>>>>> What was done there was to run a P + FF control based on the motor
>>>>>>>>> encoder and an I control based on the linear scales.
>>>>>>>>>
>>>>>>>>> Then the two controllers were summed together to create a PID
>>>>>>>>> controller, but with I using a different feedback source than P and
>>>>>> D.
>>>>>>>>> --
>>>>>>>>> atp
>>>>>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is
>>>>>>>>> designed for the especial use of mechanical geniuses, daredevils and
>>>>>>>>> lunatics."
>>>>>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> Emc-users mailing list
>>>>>>>>> Emc...@li...
>>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>>>>
>>> Cheers, Gene Heskett, CET.
>>> --
>>> "There are four boxes to be used in defense of liberty:
>>>   soap, ballot, jury, and ammo. Please use in that order."
>>> -Ed Howdershelt (Author, 1940)
>>> If we desire respect for the law, we must first make the law respectable.
>>>   - Louis D. Brandeis
>>> Don't poison our oceans, interdict drugs at the src.
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> Emc-users mailing list
>>> Emc...@li...
>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li...
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Cheers, Gene Heskett, CET.
-- 
"There are four boxes to be used in defense of liberty:
  soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
  - Louis D. Brandeis
Don't poison our oceans, interdict drugs at the src.

Re: [Emc-users] setting up dual PID loops for servo encodersandscales

[Dave E. <den...@ch...>]

Hi Andrew et al

I have a cinci contourmaster set up with US made glass scales and a rotary encoder on the ballscrew. I’m in transition to stepper-servos but progressing slowly. 
When I started this process I did a manual check with the hand crank vs the X axis scale. Proceeding in the positive direction I manually moved in 1” increments, ie 4 turns of the hand wheel. Even in this early 1960’s machine the glass scale was dead on. Since I’m protective of the US scale I removed it and installed a Chinese scale.
Both scales have a reference channel spaced with markers 50 mm apart. I suspect the US made scale has guard ticks either side of the reference mark. I know the Chinese one's do. 
Homing procedure was simple. I installed a laser diode and a tab with a hole in it at the end of the axis and manually homed to that before kicking off a home of the machine. Z was done by manually moving Z to the upper stop. If I positioned the tab and or Z stop correctly it never had to move more than ~ 3 mm to index. All of this used the normal homing procedure. Scan past the index and capture the position of index then move as necessary to home. It is my impression that homing should be done in that manner and not dual channel but after homing position seeking uses both signals but I have no data to back this up! However, given the nature of linear scales one might do just as well to use linear scale for position and shaft encoder on the motor for velocity. The system on my Mazak used a resolver on the servo motor geared (?) 7:1 and 1.6:1 to the ball screw. Those numbers are from memory and a long time ago i.e a couple of years before we did the Mazak at Galesburg. 
When I get the machine running with stepper-servos I will probably try using the R channel for homing.  Thanks for listening. Rant OFF.

Dave

> On Apr 18, 2026, at 10:49 PM, andrew beck <and...@gm...> wrote:
> 
> hey guys
> 
> just reporting back here with my success with the dual feedback
> 
> i have 0.1mm backlash still in the ballscrew or somewhere
> 
> and i have a magnetic scale on the machine also
> 
> with a encoder on the end of the ballscrew
> 
> i copied the examples on online of how they did that massive mill and its
> working awesome
> 
> the mill rapids down or feeds down to 0.02 to 0.05 and then the I value
> from the second PID takes over and moves the last tiny bit
> 
> which takes a second or so
> 
> and it stops right where it should everytime within 0.01mm  the scale says
> it's perfect to 0.003 on the screen.  and no dithering
> 
> next issue thought is homing with index
> 
> either to the motor encoder or scale z pulse
> 
> 
> 
> i have my x and y axis homing perfectly with encoder index
> 
> but i can't get linuxcnc to home this z axis to index.  homing without
> index works fine though.
> 
> i think it is because linuxcnc internals throws a hissy fit because i have
> a hacked up PID system with two forms of feedback getting summed together
> 
> any ideas would be great
> 
> cheers
> 
> Andrew
> 
> On Mon, Jan 5, 2026 at 11:04 AM gene heskett <ghe...@sh...> wrote:
> 
>> On 1/4/26 01:36, gene heskett wrote:
>>> On 1/4/26 00:23, andrew beck wrote:
>>>> hey stuart
>>>> 
>>>> yeah the ballscrew is connected both ends.  i think one end has the big
>>>> angular contact bearings etc
>>>> 
>>>> and the other only has deep groove ends probably (its much smaller
>>>> than the
>>>> driving end)
>>>> 
>>>> on my other two cnc mills they have angular contact bearings both
>>>> ends and
>>>> the screws are stretched between them slightly with a tiny bit of
>>>> preload
>>>> 
>> Probably should clarify here. The tension isn't meant to stretch the screw,
>> but to pull it tight enough there's no lengthwise backlash under normal
>> working loads despite a few microns of wear.  On my sheldon, the z screw
>> has only a sliding ball bearing on the right end, so the double bearing on
>> the left controls the end play.  After a decade of light use, I'm still
>> under 2
>> thou of play acc a .0001 dial.
>> 
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>>>> 
>>>> hey guys
>>>> 
>>>> i was reading the link that sam sent two and it looks like the two Pid
>>>> loops are running side by side  and then the outputs are added together
>>>> before going to the servo drive
>>>> 
>>>> would i be correct in thinking that they are using the "sum"
>>>> component in
>>>> linuxcnc to do that?
>>>> 
>>>> if so this is getting pretty simple
>>>> 
>>>> cheers
>>>> 
>>>> andrew
>>>> 
>>>> On Fri, Jan 2, 2026 at 3:07 PM Stuart Stevenson <st...@gm...>
>>>> wrote:
>>>> 
>>>>> HI,
>>>>>  I don't think the LinuxCNC control scheme is cascaded or nested. I
>>>>> would
>>>>> call it parallel.
>>>>> 
>>>>>  The only backlash problem I can imagine is if the backlash causes the
>>>>> motor to dither trying to maintain position because cutting forces
>>>>> move the
>>>>> axis enough to cause the control to try to correct the axis position.
>>>>> 
>>>>>  Is the ball screw supported on each end? If it is, then, is it
>>>>> possible
>>>>> the screw has some stretch preload.
>>>>> 
>>>>> regards
>>>>> Stuart
>>>>> 
>>>>> On Thu, Jan 1, 2026 at 4:10 PM andrew beck <and...@gm...>
>>>>> wrote:
>>>>> 
>>>>>> hey guys
>>>>>> sam i just looked at that link you sent
>>>>>> 
>>>>>> that looks pretty cool
>>>>>> 
>>>>>> only thing is i don't know is if it will work to reduce the backlash
>>>>> issue
>>>>>> i am getting.  I have about 0.10mm of backlash on each axis.  half of
>>>>> that
>>>>>> is from the thrust bearings which is fixable with new bearings
>>>>>> the rest is from the ball nut i think and i am not willing to fix that
>>> Those tiny ball screws stuart sold me 25 years ago were just a hair
>>> sloppy.
>>> I found the balls .001 bigger on ebay and restuffed the nuts. One of them
>>> is in the Y of my sheldon, and has about a thou of backlash today. I had
>>> to make a cage for the nut with teeny grub screws to stop the nuts end-
>>> play in the cage.  So oversized balls are one possibility. Ticklish
>>> work tho.
>>>>>> 
>>>>>> but i can only try it.
>>>>>> 
>>>>>> does anyone want to have a go with making a config like they did?  one
>>>>> axis
>>>>>> would be best  I am struggling to get my head around the different
>>>>> layers.
>>>>>> i probably need to write it all out or use a diagram or something.
>>>>>> 
>>>>>> regardless i am sure i will work it out.  just might take some brain
>>>>> cells
>>>>>> 
>>>>>> 
>>>>>> cheers
>>>>>> 
>>>>>> Andrew
>>>>>> 
>>>>>> On Fri, Jan 2, 2026 at 4:54 AM Sam Sokolik <sam...@gm...>
>> wrote:
>>>>>> 
>>>>>>> This was also John k..  I would trust his solution.  He is the one
>>>>>>> that
>>>>>>> came up with hal in linuxcnc... (Among other things).
>>>>>>> 
>>>>>>> On Thu, Jan 1, 2026, 9:49 AM andy pugh <bod...@gm...> wrote:
>>>>>>> 
>>>>>>>> On Thu, 1 Jan 2026 at 15:41, andy pugh <bod...@gm...> wrote:
>>>>>>>>> On Wed, 31 Dec 2025 at 22:14, andrew beck <
>>>>> and...@gm...>
>>>>>>>> wrote:
>>>>>>>>>> just looking for a config example if possible for a mesa card
>>>>> from
>>>>>>>> someone
>>>>>>>>>> that has this nested PID loop setup.
>>>>>>>>> This may not be as effective as you would hope. Cascaded PID
>>>>> loops...
>>>>>>>> Actually, what was done with the MPM jigmill wasn't a cascaded PID.
>>>>>>>> What was done there was to run a P + FF control based on the motor
>>>>>>>> encoder and an I control based on the linear scales.
>>>>>>>> 
>>>>>>>> Then the two controllers were summed together to create a PID
>>>>>>>> controller, but with I using a different feedback source than P and
>>>>> D.
>>>>>>>> --
>>>>>>>> atp
>>>>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is
>>>>>>>> designed for the especial use of mechanical geniuses, daredevils and
>>>>>>>> lunatics."
>>>>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912
>>>>>>>> 
>>>>>>>> 
>>>>>>>> _______________________________________________
>>>>>>>> Emc-users mailing list
>>>>>>>> Emc...@li...
>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>>> 
>>>>>>> 
>> Cheers, Gene Heskett, CET.
>> --
>> "There are four boxes to be used in defense of liberty:
>>  soap, ballot, jury, and ammo. Please use in that order."
>> -Ed Howdershelt (Author, 1940)
>> If we desire respect for the law, we must first make the law respectable.
>>  - Louis D. Brandeis
>> Don't poison our oceans, interdict drugs at the src.
>> 
>> 
>> 
>> 
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li...
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>> 
> 
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] setting up dual PID loops for servo encodersandscales

[andrew b. <and...@gm...>]

hey guys

just reporting back here with my success with the dual feedback

i have 0.1mm backlash still in the ballscrew or somewhere

and i have a magnetic scale on the machine also

with a encoder on the end of the ballscrew

i copied the examples on online of how they did that massive mill and its
working awesome

the mill rapids down or feeds down to 0.02 to 0.05 and then the I value
from the second PID takes over and moves the last tiny bit

which takes a second or so

and it stops right where it should everytime within 0.01mm  the scale says
it's perfect to 0.003 on the screen.  and no dithering

next issue thought is homing with index

either to the motor encoder or scale z pulse



i have my x and y axis homing perfectly with encoder index

but i can't get linuxcnc to home this z axis to index.  homing without
index works fine though.

i think it is because linuxcnc internals throws a hissy fit because i have
a hacked up PID system with two forms of feedback getting summed together

any ideas would be great

cheers

Andrew

On Mon, Jan 5, 2026 at 11:04 AM gene heskett <ghe...@sh...> wrote:

> On 1/4/26 01:36, gene heskett wrote:
> > On 1/4/26 00:23, andrew beck wrote:
> >> hey stuart
> >>
> >> yeah the ballscrew is connected both ends.  i think one end has the big
> >> angular contact bearings etc
> >>
> >> and the other only has deep groove ends probably (its much smaller
> >> than the
> >> driving end)
> >>
> >> on my other two cnc mills they have angular contact bearings both
> >> ends and
> >> the screws are stretched between them slightly with a tiny bit of
> >> preload
> >>
> Probably should clarify here. The tension isn't meant to stretch the screw,
> but to pull it tight enough there's no lengthwise backlash under normal
> working loads despite a few microns of wear.  On my sheldon, the z screw
> has only a sliding ball bearing on the right end, so the double bearing on
> the left controls the end play.  After a decade of light use, I'm still
> under 2
> thou of play acc a .0001 dial.
>
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> >>
> >> hey guys
> >>
> >> i was reading the link that sam sent two and it looks like the two Pid
> >> loops are running side by side  and then the outputs are added together
> >> before going to the servo drive
> >>
> >> would i be correct in thinking that they are using the "sum"
> >> component in
> >> linuxcnc to do that?
> >>
> >> if so this is getting pretty simple
> >>
> >> cheers
> >>
> >> andrew
> >>
> >> On Fri, Jan 2, 2026 at 3:07 PM Stuart Stevenson <st...@gm...>
> >> wrote:
> >>
> >>> HI,
> >>>   I don't think the LinuxCNC control scheme is cascaded or nested. I
> >>> would
> >>> call it parallel.
> >>>
> >>>   The only backlash problem I can imagine is if the backlash causes the
> >>> motor to dither trying to maintain position because cutting forces
> >>> move the
> >>> axis enough to cause the control to try to correct the axis position.
> >>>
> >>>   Is the ball screw supported on each end? If it is, then, is it
> >>> possible
> >>> the screw has some stretch preload.
> >>>
> >>> regards
> >>> Stuart
> >>>
> >>> On Thu, Jan 1, 2026 at 4:10 PM andrew beck <and...@gm...>
> >>> wrote:
> >>>
> >>>> hey guys
> >>>> sam i just looked at that link you sent
> >>>>
> >>>> that looks pretty cool
> >>>>
> >>>> only thing is i don't know is if it will work to reduce the backlash
> >>> issue
> >>>> i am getting.  I have about 0.10mm of backlash on each axis.  half of
> >>> that
> >>>> is from the thrust bearings which is fixable with new bearings
> >>>> the rest is from the ball nut i think and i am not willing to fix that
> > Those tiny ball screws stuart sold me 25 years ago were just a hair
> > sloppy.
> > I found the balls .001 bigger on ebay and restuffed the nuts. One of them
> > is in the Y of my sheldon, and has about a thou of backlash today. I had
> > to make a cage for the nut with teeny grub screws to stop the nuts end-
> > play in the cage.  So oversized balls are one possibility. Ticklish
> > work tho.
> >>>>
> >>>> but i can only try it.
> >>>>
> >>>> does anyone want to have a go with making a config like they did?  one
> >>> axis
> >>>> would be best  I am struggling to get my head around the different
> >>> layers.
> >>>> i probably need to write it all out or use a diagram or something.
> >>>>
> >>>> regardless i am sure i will work it out.  just might take some brain
> >>> cells
> >>>>
> >>>>
> >>>> cheers
> >>>>
> >>>> Andrew
> >>>>
> >>>> On Fri, Jan 2, 2026 at 4:54 AM Sam Sokolik <sam...@gm...>
> wrote:
> >>>>
> >>>>> This was also John k..  I would trust his solution.  He is the one
> >>>>> that
> >>>>> came up with hal in linuxcnc... (Among other things).
> >>>>>
> >>>>> On Thu, Jan 1, 2026, 9:49 AM andy pugh <bod...@gm...> wrote:
> >>>>>
> >>>>>> On Thu, 1 Jan 2026 at 15:41, andy pugh <bod...@gm...> wrote:
> >>>>>>> On Wed, 31 Dec 2025 at 22:14, andrew beck <
> >>> and...@gm...>
> >>>>>> wrote:
> >>>>>>>> just looking for a config example if possible for a mesa card
> >>> from
> >>>>>> someone
> >>>>>>>> that has this nested PID loop setup.
> >>>>>>> This may not be as effective as you would hope. Cascaded PID
> >>> loops...
> >>>>>> Actually, what was done with the MPM jigmill wasn't a cascaded PID.
> >>>>>> What was done there was to run a P + FF control based on the motor
> >>>>>> encoder and an I control based on the linear scales.
> >>>>>>
> >>>>>> Then the two controllers were summed together to create a PID
> >>>>>> controller, but with I using a different feedback source than P and
> >>> D.
> >>>>>> --
> >>>>>> atp
> >>>>>> "A motorcycle is a bicycle with a pandemonium attachment and is
> >>>>>> designed for the especial use of mechanical geniuses, daredevils and
> >>>>>> lunatics."
> >>>>>> — George Fitch, Atlanta Constitution Newspaper, 1912
> >>>>>>
> >>>>>>
> >>>>>> _______________________________________________
> >>>>>> Emc-users mailing list
> >>>>>> Emc...@li...
> >>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>>>>>
> >>>>>
> Cheers, Gene Heskett, CET.
> --
> "There are four boxes to be used in defense of liberty:
>   soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author, 1940)
> If we desire respect for the law, we must first make the law respectable.
>   - Louis D. Brandeis
> Don't poison our oceans, interdict drugs at the src.
>
>
>
>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users
>

Re: [Emc-users] Small part

[gene h. <ghe...@sh...>]

On 4/13/26 11:31, Dave Engvall wrote:
> Warning! Rant ahead!
> Ouch! 2,4,5 T (agent orange) has a bad rep! You dodged the bullet.
Did I?  All 3 of my first wifes children I made are gone, the 2 girls 
with cancer & the boy from trying tto mix scotch and a hundai, and now 
my middle son by wife #2 is grand mall.
>   Statistics of ones are a bitch! When young one does all sorts of jobs.
Absolutely.  All to keep buying groceries for my tribes.
> HS picked fruit, awful job. For 4 summers I was a forest service fire lookout; isolated lonely but financed a degree. Got drafted when the Berlin Wall went up; assigned to  Dugway Proving Ground as a 939.30. Did plague survey and then worked on a way to use chemicals detectable at low levels  to quantitate distribution of aerosol sprayed on a large grid, think nerve gas, etc. Moved back to Pullman and did c14 and H3 dating. C14 for archeological sites and deep aquifers and H3 for shallow wells. When carbon dating went slack for a month I got loaned to Polymer Chemistry to do a Mol Wt determination on straiten ( a long-chain polysaccharide extract from larch.  Next was a job as a chemist/microbiologist for Wa Dept of Agriculture checking to see if ag products met label guarantee on feed and fertilizer. Protein, fat, and fiber on feeds and N,P,K on fertilizer. Various drugs and antibiotics in feed, microscopic analysis of feed and fertilizer for specific contents and adulteration. Being lazy I managed to sneak a pdp11 into the lab by saying what it would do not what it was. We replaced readout on the Perkin-Elmer AA with the 11 and 12 bit A/D. I did the electronics and one of my chemists did the software. It did the job until we replaced it with a new AA that still didn’t have the capabilities of our custom system but was off the shelf. I never did get the lab system up to the point where I could report results directly off the database. Administrators tend to get paid by how many people they supervise not by what the do so there Is no incentive to be efficient. Retired the first day I could. Good decision!
>
>> On Apr 10, 2026, at 5:14 AM, gene heskett <ghe...@sh...> wrote:
>>
>> On 4/9/26 17:38, Dave Engvall wrote:
>>> Many years ago I had pretty good luck with epoxy catalyzed with  trimellitic anhydride
>>> The epoxy was a bright yellow and was used to seal cartridge heaters in a reactor operating at a couple of atm with a charge of water and powdered zinc. But then that was 60+ years ago, YMMV.
>>> IOW Good luck.
>>>
>>> Dave
>>>
>>> Note for the curious: the idea was to recover the hydrogen from the water and
>>>   then convert it to methane and count the amt of tritium in the methane. Tritium has a pretty short half-life so much easier to count and get good counting statistics than C14. Don’t think we were ever even close to successful.
>> I've had no idea you were into the chemistry of that sort.  Good to hear from you. I spent a month or so in my mid teens walking around in a 2500 gallon stock tank, up to my gonads in warm liquid with a boat paddle mixing it that we eventually sold to the farmers as 2-4-5T weed killer  Took me about a month to get that stink out of my nose after I got a better job in electronics.  Probably not that good for my potential git if I ever found me a woman. Fortunately one found me but it was about 5 years later.
>> Now I've outlived 3 and the 3 git that first one gave but now I'm 91 and still here.  Glad to see you are too, Dave.
>>>
>>>
>>>   On Jan 31, 2026, at 3:48 PM, gene heskett <ghe...@sh...> wrote:
>>>> On 1/31/26 17:58, Stuart Stevenson wrote:
>>>>> LinuxCNC guys,
>>>>>   I don't know how I included LinuxCNC guys in this email. It must have been
>>>>> me trying to reply to an email using my Iphone. I literally hate it. It
>>>>> updates as it wishes. The updates modify anything Apple wants to. I have to
>>>>> be constantly relearning most everything. I feel like I am using a hatchet
>>>>> with the sharp side cut off. When you cut the sharp side off a hatchet, you
>>>>> end up with a hammer.
An opration often missed until the hammer falls. . .
{snip}
>>>> Take care of #1.
>>>>> I love the LinuxCNC community!
>>>> Proving forever that you are "one of us".  Thank you.
And proud of it.
>>>>> Regards,
>>>>> Stuart
>>>>>
>>>>>
>>>>> On Sat, Jan 31, 2026 at 4:11 PM Stuart Stevenson <st...@gm...> wrote:
>>>>>
>>>>>> LOL! Andy,
>>>>>>
>>>>>>   I have that on there only to screw with government snoops. I don't expect
>>>>>> them to honor it. For one thing, they must have some honor to begin with
>>>>>> before they try to use it.
good point, Stuart..
>>>>>>
>>>>>> On Sat, Jan 31, 2026 at 12:54 PM Chris Albertson <
>>>>>> alb...@gm...> wrote:
>>>>>>
>>>>>>> Plan on a 360–450°C hot end, 120–160°C bed, and a fully enclosed,
>>>>>>> actively heated chamber (70–150°C).       But general guidelines are not
>>>>>>> enough.  It depends on the exact brand of filament and your own testing.
>>>>>>>
>>>>>>> The best bed heater is dirt-cheap.   You put direct mains AC on the
>>>>>>> heater and control it with a contractor that is designed for water heaters
>>>>>>> or electric home heating.   Same for the enclosure heat.   You need
>>>>>>> insulation on the enclosure; plexiglass will not be enough, the ceramic
>>>>>>> felt used on stoves works.
>>>>>>>
>>>>>>> A cheaper solution is to re-engineer your product so that it does not
>>>>>>> require PEEK.
>>>>>>>
>>>>>>> OK, you can’t redesign the part?  You can send it out to a commercial
>>>>>>> printer.      But then, “why PEEK?” have them print it in stainless steel.
>>>>>>> On Jan 31, 2026, at 4:44 AM, gene heskett <ghe...@sh...> wrote:
>>>>>>>
>>>>>>> On 1/30/26 23:22, Stuart Stevenson wrote:
>>>>>>>>> Addressee is the intended audience.1 mm
>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>>> read
>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>>> saving or
>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>> correspondence.
>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> ---------- Forwarded message ---------
>>>>>>>>> From: Stuart Stevenson<st...@gm...>
>>>>>>>>> Date: Fri, Jan 30, 2026 at 10:06 PM
>>>>>>>>> Subject: Re: Small part
>>>>>>>>> To: Sack, Richard<ric...@wi...>
>>>>>>>>> CC: Chris Rempe<chr...@id...>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Chris, are you able to consider a part from a private individual? I
>>>>>>> have a
>>>>>>>>> single small PEEK part. Ultim 1010 would be a little better. It is a
>>>>>>> repair
>>>>>>>>> part for an automotive radiator. I can supply a solid model and/or an
>>>>>>> STL
>>>>>>>>> file.
>>>>>>>> Stuart:
>>>>>>>> What sort of temps are needed for PEEK? I have what I thought was a
>>>>>>> comprehensive chart of such, but it doesn't have a reference for PEEK.
>>>>>>> Apparently the composer of this chart wasn't concerned with materials
>>>>>>> needing more than 300C nozzles. Even that is getting pretty far into the
>>>>>>> far end of heater lifetimes mortality curve. I do some PC, but even at 285C
>>>>>>> I'm losing heaters in 100-150 hrs. That also needs a bed temp around 100C,
>>>>>>> well beyond most under $1500 printers. The printer I've rebuilt to do that,
>>>>>>> an Ender 5 Plus now has 72 volt closed loop stepper/servo XY motors, and a
>>>>>>> 36 volt bed supply that an get to 125C. I also have a Sovol sv08 MAX. Which
>>>>>>> is acting like its going to be my next fav printer. Either one warms up a
>>>>>>> 15 amp breaker in the service.
>>>>>>>>> Thanks
>>>>>>>>> Stuart Stevenson
>>>>>>>>> 4638 Farmstead Ct
>>>>>>>>> Bel Aire, Ks 67220-1617
>>>>>>>>> 316-258-0953
>>>>>>>>> st...@gm...
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Addressee is the intended audience.
>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>>> read
>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>>> saving or
>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>> correspondence.
>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On Fri, Jan 30, 2026 at 9:49 PM Stuart Stevenson<st...@gm...>
>>>>>>> wrote:
>>>>>>>>>> Thank you.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Addressee is the intended audience.
>>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>>> read
>>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>>> saving or
>>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>>> correspondence.
>>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Fri, Jan 30, 2026 at 3:26 PM Sack, Richard<
>>>>>>> ric...@wi...>
>>>>>>>>>> wrote:
>>>>>>>>>>
>>>>>>>>>>> I am unable to print PEEK.
>>>>>>>>>>>
>>>>>>>>>>> PEEK needs a very high temperature nozzle, very hot build chamber,
>>>>>>> etc.
>>>>>>>>>>> Chris Rempe has fancy and very expensive 3D printers; he may be able
>>>>>>> to
>>>>>>>>>>> help you.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> *Richard Sack *Research Support Manager & Design Engineer
>>>>>>>>>>> Project Innovation Hub | College of Engineering
>>>>>>>>>>> John Bardo Center 105
>>>>>>>>>>> Wichita State University |1845 Fairmount Street Wichita, Kansas 67260
>>>>>>>>>>> <
>>>>>>> https://www.google.com/maps/search/1845+Fairmount+Street+Wichita,+Kansas+67260?entry=gmail&source=g
>>>>>>>>>>> | Box 209
>>>>>>>>>>> Schedule a meeting
>>>>>>>>>>> <
>>>>>>> https://outlook.office.com/bookwithme/user/0dc...@wi...?anonymous&ep=plink
>>>>>>>>>>> (316) 204-1341
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> *From:* Stuart Stevenson<st...@gm...>
>>>>>>>>>>> *Sent:* Friday, January 30, 2026 1:10 PM
>>>>>>>>>>> *To:* Sack, Richard<ric...@wi...>
>>>>>>>>>>> *Subject:* Small part
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Richard,
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Are you able to print PEEK?
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Thanks
>>>>>>>>>>>
>>>>>>>>>>> Stuart
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Addressee is the intended audience.
>>>>>>>>>>>
>>>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>>> read
>>>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>>> saving or
>>>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>>>> correspondence.
>>>>>>>>>>>
>>>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> Emc-users mailing list
>>>>>>>>> Emc...@li...
>>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>>> Cheers, Gene Heskett, CET.
>>>>>>>> --
>>>>>>>> "There are four boxes to be used in defense of liberty:
>>>>>>>> soap, ballot, jury, and ammo. Please use in that order."
>>>>>>>> -Ed Howdershelt (Author, 1940)
>>>>>>>> If we desire respect for the law, we must first make the law
>>>>>>> respectable.
>>>>>>>> - Louis D. Brandeis
>>>>>>>> Don't poison our oceans, interdict drugs at the src.
>>>>>>>>
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> Emc-users mailing list
>>>>>>>> Emc...@li... <mailto:Emc...@li...
>>>>>>>>
>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>> _______________________________________________
>>>>>>> Emc-users mailing list
>>>>>>> Emc...@li...
>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>>
>>>>>> --
>>>>>> Addressee is the intended audience.
>>>>>> If you are not the addressee then my consent is not given for you to read
>>>>>> this email furthermore it is my wish you would close this without saving or
>>>>>> reading, and cease and desist from saving or opening my private
>>>>>> correspondence.
>>>>>> Thank you for honoring my wish.
>>>>>>
>>>>>>
>>>> Cheers, Gene Heskett, CET.
>>>> -- 
>>>> "There are four boxes to be used in defense of liberty:
>>>> soap, ballot, jury, and ammo. Please use in that order."
>>>> -Ed Howdershelt (Author, 1940)
>>>> If we desire respect for the law, we must first make the law respectable.
>>>> - Louis D. Brandeis
>>>> Don't poison our oceans, interdict drugs at the src.
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Emc-users mailing list
>>>> Emc...@li... <mailto:Emc...@li...> <mailto:Emc...@li...>
>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>> _______________________________________________
>>> Emc-users mailing list
>>> Emc...@li... <mailto:Emc...@li...>
>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>> Cheers, Gene Heskett, CET.
>> -- 
>> "There are four boxes to be used in defense of liberty:
>> soap, ballot, jury, and ammo. Please use in that order."
>> -Ed Howdershelt (Author, 1940)
>> If we desire respect for the law, we must first make the law respectable.
>> - Louis D. Brandeis
>> Don't poison our oceans, interdict drugs at the src.
>>
>>
>>
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li... <mailto:Emc...@li...>
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Cheers, Gene Heskett, CET.
-- 
"There are four boxes to be used in defense of liberty:
  soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
  - Louis D. Brandeis
Don't poison our oceans, interdict drugs at the src.

Re: [Emc-users] Small part

[Dave E. <den...@ch...>]

Warning! Rant ahead!
Ouch! 2,4,5 T (agent orange) has a bad rep! You dodged the bullet. Statistics of ones are a bitch! When young one does all sorts of jobs.
HS picked fruit, awful job. For 4 summers I was a forest service fire lookout; isolated lonely but financed a degree. Got drafted when the Berlin Wall went up; assigned to  Dugway Proving Ground as a 939.30. Did plague survey and then worked on a way to use chemicals detectable at low levels  to quantitate distribution of aerosol sprayed on a large grid, think nerve gas, etc. Moved back to Pullman and did c14 and H3 dating. C14 for archeological sites and deep aquifers and H3 for shallow wells. When carbon dating went slack for a month I got loaned to Polymer Chemistry to do a Mol Wt determination on straiten ( a long-chain polysaccharide extract from larch.  Next was a job as a chemist/microbiologist for Wa Dept of Agriculture checking to see if ag products met label guarantee on feed and fertilizer. Protein, fat, and fiber on feeds and N,P,K on fertilizer. Various drugs and antibiotics in feed, microscopic analysis of feed and fertilizer for specific contents and adulteration. Being lazy I managed to sneak a pdp11 into the lab by saying what it would do not what it was. We replaced readout on the Perkin-Elmer AA with the 11 and 12 bit A/D. I did the electronics and one of my chemists did the software. It did the job until we replaced it with a new AA that still didn’t have the capabilities of our custom system but was off the shelf. I never did get the lab system up to the point where I could report results directly off the database. Administrators tend to get paid by how many people they supervise not by what the do so there Is no incentive to be efficient. Retired the first day I could. Good decision!

> On Apr 10, 2026, at 5:14 AM, gene heskett <ghe...@sh...> wrote:
> 
> On 4/9/26 17:38, Dave Engvall wrote:
>> Many years ago I had pretty good luck with epoxy catalyzed with  trimellitic anhydride
>> The epoxy was a bright yellow and was used to seal cartridge heaters in a reactor operating at a couple of atm with a charge of water and powdered zinc. But then that was 60+ years ago, YMMV.
>> IOW Good luck.
>> 
>> Dave
>> 
>> Note for the curious: the idea was to recover the hydrogen from the water and
>>  then convert it to methane and count the amt of tritium in the methane. Tritium has a pretty short half-life so much easier to count and get good counting statistics than C14. Don’t think we were ever even close to successful.
> I've had no idea you were into the chemistry of that sort.  Good to hear from you. I spent a month or so in my mid teens walking around in a 2500 gallon stock tank, up to my gonads in warm liquid with a boat paddle mixing it that we eventually sold to the farmers as 2-4-5T weed killer  Took me about a month to get that stink out of my nose after I got a better job in electronics.  Probably not that good for my potential git if I ever found me a woman. Fortunately one found me but it was about 5 years later.
> Now I've outlived 3 and the 3 git that first one gave but now I'm 91 and still here.  Glad to see you are too, Dave.
>> 
>> 
>> 
>>  On Jan 31, 2026, at 3:48 PM, gene heskett <ghe...@sh...> wrote:
>>> On 1/31/26 17:58, Stuart Stevenson wrote:
>>>> LinuxCNC guys,
>>>>  I don't know how I included LinuxCNC guys in this email. It must have been
>>>> me trying to reply to an email using my Iphone. I literally hate it. It
>>>> updates as it wishes. The updates modify anything Apple wants to. I have to
>>>> be constantly relearning most everything. I feel like I am using a hatchet
>>>> with the sharp side cut off. When you cut the sharp side off a hatchet, you
>>>> end up with a hammer.
>>>> 
>>>>  I have an automotive radiator to repair. The part is plastic. I have two
>>>> 3D printers, neither enclosed. The motor was extremely overheated by
>>>> running out of coolant. Fortunately(I think 🤣), it still runs good. Shows
>>>> no sigh of damage except of the pressure ring in the filler neck is eroded
>>>> away. Using testing liquid I detect no presence of exhaust gases in the
>>>> coolant and the exhaust system looks clean.
>>>>  Researching what plastic to print I chose PEEK because of the high glass
>>>> transition temperature - ~140C. I asked Richard at Wichita State Univeristy
>>>> if he could print PEEK. Richard does amazing things. He doesn't have a
>>>> printer that will print PEEK. Richards reply introduced me to Chris
>>>> Rempe(also at WSU). He has a printer that will print Ultim 1010. Ultim 1010
>>>> has a higher glass transition temperature, so I replied to ask him if he
>>>> could do it.
>>>>  Somehow, I included you guys. I haven't heard from Chis Rempe, but this
>>>> project will probably become a radiator replacement as a new radiator from
>>>> RockAuto is USD85.00 up to USD125.00 plus shipping.
>>>>  This car belongs to my sister-in-law. I was hoping for a quick little
>>>> 'magic' repair. Heh, not likely.
>>> Sorry Stuart, but at a 140C glass temp and 15 to 20 psi pressure
>>> I don't think even PEEK is a long term solution.  I've bought some
>>> stuff from Rock Auto in the past. Everything fit.  But I quite buying
>>> used vehicles with fogged up headlights.
>>> 
>>> I share your views on govmnt and hell phones. I have one, but
>>> since I've been 99% retired for 23 years now, just some occasional
>>> consulting with our local daytime AM'er, I let the sim card expire
>>> about 9 years ago. I miss it like a broken leg.  If I ever get the urge
>>> to make the grand tour west of the river to see my 4  boys again I
>>> might see about a new card. But at 91, macular degeneration
>>> is spoiling my enjoyment for driving the length of SD at WOT & 3 AM
>>> 
>>> Take care of #1.
>>>> I love the LinuxCNC community!
>>> Proving forever that you are "one of us".  Thank you.
>>>> Regards,
>>>> Stuart
>>>> 
>>>> 
>>>> On Sat, Jan 31, 2026 at 4:11 PM Stuart Stevenson <st...@gm...> wrote:
>>>> 
>>>>> LOL! Andy,
>>>>> 
>>>>>  I have that on there only to screw with government snoops. I don't expect
>>>>> them to honor it. For one thing, they must have some honor to begin with
>>>>> before they try to use it.
>>>>> 
>>>>> On Sat, Jan 31, 2026 at 12:54 PM Chris Albertson <
>>>>> alb...@gm...> wrote:
>>>>> 
>>>>>> Plan on a 360–450°C hot end, 120–160°C bed, and a fully enclosed,
>>>>>> actively heated chamber (70–150°C).       But general guidelines are not
>>>>>> enough.  It depends on the exact brand of filament and your own testing.
>>>>>> 
>>>>>> The best bed heater is dirt-cheap.   You put direct mains AC on the
>>>>>> heater and control it with a contractor that is designed for water heaters
>>>>>> or electric home heating.   Same for the enclosure heat.   You need
>>>>>> insulation on the enclosure; plexiglass will not be enough, the ceramic
>>>>>> felt used on stoves works.
>>>>>> 
>>>>>> A cheaper solution is to re-engineer your product so that it does not
>>>>>> require PEEK.
>>>>>> 
>>>>>> OK, you can’t redesign the part?  You can send it out to a commercial
>>>>>> printer.      But then, “why PEEK?” have them print it in stainless steel.
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>>> On Jan 31, 2026, at 4:44 AM, gene heskett <ghe...@sh...> wrote:
>>>>>>> 
>>>>>>> On 1/30/26 23:22, Stuart Stevenson wrote:
>>>>>>>> Addressee is the intended audience.1 mm
>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>> read
>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>> saving or
>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>> correspondence.
>>>>>>>> Thank you for honoring my wish.
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> ---------- Forwarded message ---------
>>>>>>>> From: Stuart Stevenson<st...@gm...>
>>>>>>>> Date: Fri, Jan 30, 2026 at 10:06 PM
>>>>>>>> Subject: Re: Small part
>>>>>>>> To: Sack, Richard<ric...@wi...>
>>>>>>>> CC: Chris Rempe<chr...@id...>
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Chris, are you able to consider a part from a private individual? I
>>>>>> have a
>>>>>>>> single small PEEK part. Ultim 1010 would be a little better. It is a
>>>>>> repair
>>>>>>>> part for an automotive radiator. I can supply a solid model and/or an
>>>>>> STL
>>>>>>>> file.
>>>>>>> Stuart:
>>>>>>> What sort of temps are needed for PEEK? I have what I thought was a
>>>>>> comprehensive chart of such, but it doesn't have a reference for PEEK.
>>>>>> Apparently the composer of this chart wasn't concerned with materials
>>>>>> needing more than 300C nozzles. Even that is getting pretty far into the
>>>>>> far end of heater lifetimes mortality curve. I do some PC, but even at 285C
>>>>>> I'm losing heaters in 100-150 hrs. That also needs a bed temp around 100C,
>>>>>> well beyond most under $1500 printers. The printer I've rebuilt to do that,
>>>>>> an Ender 5 Plus now has 72 volt closed loop stepper/servo XY motors, and a
>>>>>> 36 volt bed supply that an get to 125C. I also have a Sovol sv08 MAX. Which
>>>>>> is acting like its going to be my next fav printer. Either one warms up a
>>>>>> 15 amp breaker in the service.
>>>>>>>> Thanks
>>>>>>>> Stuart Stevenson
>>>>>>>> 4638 Farmstead Ct
>>>>>>>> Bel Aire, Ks 67220-1617
>>>>>>>> 316-258-0953
>>>>>>>> st...@gm...
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Addressee is the intended audience.
>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>> read
>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>> saving or
>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>> correspondence.
>>>>>>>> Thank you for honoring my wish.
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> On Fri, Jan 30, 2026 at 9:49 PM Stuart Stevenson<st...@gm...>
>>>>>> wrote:
>>>>>>>>> Thank you.
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>> Addressee is the intended audience.
>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>> read
>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>> saving or
>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>> correspondence.
>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>> On Fri, Jan 30, 2026 at 3:26 PM Sack, Richard<
>>>>>> ric...@wi...>
>>>>>>>>> wrote:
>>>>>>>>> 
>>>>>>>>>> I am unable to print PEEK.
>>>>>>>>>> 
>>>>>>>>>> PEEK needs a very high temperature nozzle, very hot build chamber,
>>>>>> etc.
>>>>>>>>>> 
>>>>>>>>>> Chris Rempe has fancy and very expensive 3D printers; he may be able
>>>>>> to
>>>>>>>>>> help you.
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> *Richard Sack *Research Support Manager & Design Engineer
>>>>>>>>>> Project Innovation Hub | College of Engineering
>>>>>>>>>> John Bardo Center 105
>>>>>>>>>> Wichita State University |1845 Fairmount Street Wichita, Kansas 67260
>>>>>>>>>> <
>>>>>> https://www.google.com/maps/search/1845+Fairmount+Street+Wichita,+Kansas+67260?entry=gmail&source=g
>>>>>>>>>> | Box 209
>>>>>>>>>> Schedule a meeting
>>>>>>>>>> <
>>>>>> https://outlook.office.com/bookwithme/user/0dc...@wi...?anonymous&ep=plink
>>>>>>>>>> (316) 204-1341
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> *From:* Stuart Stevenson<st...@gm...>
>>>>>>>>>> *Sent:* Friday, January 30, 2026 1:10 PM
>>>>>>>>>> *To:* Sack, Richard<ric...@wi...>
>>>>>>>>>> *Subject:* Small part
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> Richard,
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> Are you able to print PEEK?
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> Thanks
>>>>>>>>>> 
>>>>>>>>>> Stuart
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> Addressee is the intended audience.
>>>>>>>>>> 
>>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>>> read
>>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>>> saving or
>>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>>> correspondence.
>>>>>>>>>> 
>>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>> _______________________________________________
>>>>>>>> Emc-users mailing list
>>>>>>>> Emc...@li...
>>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>>> Cheers, Gene Heskett, CET.
>>>>>>> --
>>>>>>> "There are four boxes to be used in defense of liberty:
>>>>>>> soap, ballot, jury, and ammo. Please use in that order."
>>>>>>> -Ed Howdershelt (Author, 1940)
>>>>>>> If we desire respect for the law, we must first make the law
>>>>>> respectable.
>>>>>>> - Louis D. Brandeis
>>>>>>> Don't poison our oceans, interdict drugs at the src.
>>>>>>> 
>>>>>>> 
>>>>>>> _______________________________________________
>>>>>>> Emc-users mailing list
>>>>>>> Emc...@li... <mailto:Emc...@li...
>>>>>>> 
>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>> _______________________________________________
>>>>>> Emc-users mailing list
>>>>>> Emc...@li...
>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>> 
>>>>> --
>>>>> Addressee is the intended audience.
>>>>> If you are not the addressee then my consent is not given for you to read
>>>>> this email furthermore it is my wish you would close this without saving or
>>>>> reading, and cease and desist from saving or opening my private
>>>>> correspondence.
>>>>> Thank you for honoring my wish.
>>>>> 
>>>>> 
>>> Cheers, Gene Heskett, CET.
>>> -- 
>>> "There are four boxes to be used in defense of liberty:
>>> soap, ballot, jury, and ammo. Please use in that order."
>>> -Ed Howdershelt (Author, 1940)
>>> If we desire respect for the law, we must first make the law respectable.
>>> - Louis D. Brandeis
>>> Don't poison our oceans, interdict drugs at the src.
>>> 
>>> 
>>> 
>>> 
>>> _______________________________________________
>>> Emc-users mailing list
>>> Emc...@li... <mailto:Emc...@li...> <mailto:Emc...@li...>
>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>> 
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li... <mailto:Emc...@li...>
>> https://lists.sourceforge.net/lists/listinfo/emc-users
> 
> Cheers, Gene Heskett, CET.
> -- 
> "There are four boxes to be used in defense of liberty:
> soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author, 1940)
> If we desire respect for the law, we must first make the law respectable.
> - Louis D. Brandeis
> Don't poison our oceans, interdict drugs at the src.
> 
> 
> 
> _______________________________________________
> Emc-users mailing list
> Emc...@li... <mailto:Emc...@li...>
> https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Ai generated gui conversational stuff

[andrew b. <and...@gm...>]

Hey guys check this out.

Real cool

Not my work

https://youtu.be/ZJe2dT79MwA?si=jJCzhJQTxrGwyJqL

Re: [Emc-users] Small part

[gene h. <ghe...@sh...>]

On 4/9/26 17:38, Dave Engvall wrote:
> Many years ago I had pretty good luck with epoxy catalyzed with  trimellitic anhydride
> The epoxy was a bright yellow and was used to seal cartridge heaters in a reactor operating at a couple of atm with a charge of water and powdered zinc. But then that was 60+ years ago, YMMV.
> IOW Good luck.
>
> Dave
>
> Note for the curious: the idea was to recover the hydrogen from the water and
>   then convert it to methane and count the amt of tritium in the methane. Tritium has a pretty short half-life so much easier to count and get good counting statistics than C14. Don’t think we were ever even close to successful.
I've had no idea you were into the chemistry of that sort.  Good to hear 
from you. I spent a month or so in my mid teens walking around in a 2500 
gallon stock tank, up to my gonads in warm liquid with a boat paddle 
mixing it that we eventually sold to the farmers as 2-4-5T weed killer  
Took me about a month to get that stink out of my nose after I got a 
better job in electronics.  Probably not that good for my potential git 
if I ever found me a woman. Fortunately one found me but it was about 5 
years later.
Now I've outlived 3 and the 3 git that first one gave but now I'm 91 and 
still here.  Glad to see you are too, Dave.
>
>
>
>   On Jan 31, 2026, at 3:48 PM, gene heskett <ghe...@sh...> wrote:
>> On 1/31/26 17:58, Stuart Stevenson wrote:
>>> LinuxCNC guys,
>>>   I don't know how I included LinuxCNC guys in this email. It must have been
>>> me trying to reply to an email using my Iphone. I literally hate it. It
>>> updates as it wishes. The updates modify anything Apple wants to. I have to
>>> be constantly relearning most everything. I feel like I am using a hatchet
>>> with the sharp side cut off. When you cut the sharp side off a hatchet, you
>>> end up with a hammer.
>>>
>>>   I have an automotive radiator to repair. The part is plastic. I have two
>>> 3D printers, neither enclosed. The motor was extremely overheated by
>>> running out of coolant. Fortunately(I think 🤣), it still runs good. Shows
>>> no sigh of damage except of the pressure ring in the filler neck is eroded
>>> away. Using testing liquid I detect no presence of exhaust gases in the
>>> coolant and the exhaust system looks clean.
>>>   Researching what plastic to print I chose PEEK because of the high glass
>>> transition temperature - ~140C. I asked Richard at Wichita State Univeristy
>>> if he could print PEEK. Richard does amazing things. He doesn't have a
>>> printer that will print PEEK. Richards reply introduced me to Chris
>>> Rempe(also at WSU). He has a printer that will print Ultim 1010. Ultim 1010
>>> has a higher glass transition temperature, so I replied to ask him if he
>>> could do it.
>>>   Somehow, I included you guys. I haven't heard from Chis Rempe, but this
>>> project will probably become a radiator replacement as a new radiator from
>>> RockAuto is USD85.00 up to USD125.00 plus shipping.
>>>   This car belongs to my sister-in-law. I was hoping for a quick little
>>> 'magic' repair. Heh, not likely.
>> Sorry Stuart, but at a 140C glass temp and 15 to 20 psi pressure
>> I don't think even PEEK is a long term solution.  I've bought some
>> stuff from Rock Auto in the past. Everything fit.  But I quite buying
>> used vehicles with fogged up headlights.
>>
>> I share your views on govmnt and hell phones. I have one, but
>> since I've been 99% retired for 23 years now, just some occasional
>> consulting with our local daytime AM'er, I let the sim card expire
>> about 9 years ago. I miss it like a broken leg.  If I ever get the urge
>> to make the grand tour west of the river to see my 4  boys again I
>> might see about a new card. But at 91, macular degeneration
>> is spoiling my enjoyment for driving the length of SD at WOT & 3 AM
>>
>> Take care of #1.
>>> I love the LinuxCNC community!
>> Proving forever that you are "one of us".  Thank you.
>>> Regards,
>>> Stuart
>>>
>>>
>>> On Sat, Jan 31, 2026 at 4:11 PM Stuart Stevenson <st...@gm...> wrote:
>>>
>>>> LOL! Andy,
>>>>
>>>>   I have that on there only to screw with government snoops. I don't expect
>>>> them to honor it. For one thing, they must have some honor to begin with
>>>> before they try to use it.
>>>>
>>>> On Sat, Jan 31, 2026 at 12:54 PM Chris Albertson <
>>>> alb...@gm...> wrote:
>>>>
>>>>> Plan on a 360–450°C hot end, 120–160°C bed, and a fully enclosed,
>>>>> actively heated chamber (70–150°C).       But general guidelines are not
>>>>> enough.  It depends on the exact brand of filament and your own testing.
>>>>>
>>>>> The best bed heater is dirt-cheap.   You put direct mains AC on the
>>>>> heater and control it with a contractor that is designed for water heaters
>>>>> or electric home heating.   Same for the enclosure heat.   You need
>>>>> insulation on the enclosure; plexiglass will not be enough, the ceramic
>>>>> felt used on stoves works.
>>>>>
>>>>> A cheaper solution is to re-engineer your product so that it does not
>>>>> require PEEK.
>>>>>
>>>>> OK, you can’t redesign the part?  You can send it out to a commercial
>>>>> printer.      But then, “why PEEK?” have them print it in stainless steel.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> On Jan 31, 2026, at 4:44 AM, gene heskett <ghe...@sh...> wrote:
>>>>>>
>>>>>> On 1/30/26 23:22, Stuart Stevenson wrote:
>>>>>>> Addressee is the intended audience.1 mm
>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>> read
>>>>>>> this email furthermore it is my wish you would close this without
>>>>> saving or
>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>> correspondence.
>>>>>>> Thank you for honoring my wish.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> ---------- Forwarded message ---------
>>>>>>> From: Stuart Stevenson<st...@gm...>
>>>>>>> Date: Fri, Jan 30, 2026 at 10:06 PM
>>>>>>> Subject: Re: Small part
>>>>>>> To: Sack, Richard<ric...@wi...>
>>>>>>> CC: Chris Rempe<chr...@id...>
>>>>>>>
>>>>>>>
>>>>>>> Chris, are you able to consider a part from a private individual? I
>>>>> have a
>>>>>>> single small PEEK part. Ultim 1010 would be a little better. It is a
>>>>> repair
>>>>>>> part for an automotive radiator. I can supply a solid model and/or an
>>>>> STL
>>>>>>> file.
>>>>>> Stuart:
>>>>>> What sort of temps are needed for PEEK? I have what I thought was a
>>>>> comprehensive chart of such, but it doesn't have a reference for PEEK.
>>>>> Apparently the composer of this chart wasn't concerned with materials
>>>>> needing more than 300C nozzles. Even that is getting pretty far into the
>>>>> far end of heater lifetimes mortality curve. I do some PC, but even at 285C
>>>>> I'm losing heaters in 100-150 hrs. That also needs a bed temp around 100C,
>>>>> well beyond most under $1500 printers. The printer I've rebuilt to do that,
>>>>> an Ender 5 Plus now has 72 volt closed loop stepper/servo XY motors, and a
>>>>> 36 volt bed supply that an get to 125C. I also have a Sovol sv08 MAX. Which
>>>>> is acting like its going to be my next fav printer. Either one warms up a
>>>>> 15 amp breaker in the service.
>>>>>>> Thanks
>>>>>>> Stuart Stevenson
>>>>>>> 4638 Farmstead Ct
>>>>>>> Bel Aire, Ks 67220-1617
>>>>>>> 316-258-0953
>>>>>>> st...@gm...
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Addressee is the intended audience.
>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>> read
>>>>>>> this email furthermore it is my wish you would close this without
>>>>> saving or
>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>> correspondence.
>>>>>>> Thank you for honoring my wish.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Fri, Jan 30, 2026 at 9:49 PM Stuart Stevenson<st...@gm...>
>>>>> wrote:
>>>>>>>> Thank you.
>>>>>>>>
>>>>>>>>
>>>>>>>> Addressee is the intended audience.
>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>> read
>>>>>>>> this email furthermore it is my wish you would close this without
>>>>> saving or
>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>> correspondence.
>>>>>>>> Thank you for honoring my wish.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> On Fri, Jan 30, 2026 at 3:26 PM Sack, Richard<
>>>>> ric...@wi...>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> I am unable to print PEEK.
>>>>>>>>>
>>>>>>>>> PEEK needs a very high temperature nozzle, very hot build chamber,
>>>>> etc.
>>>>>>>>>
>>>>>>>>> Chris Rempe has fancy and very expensive 3D printers; he may be able
>>>>> to
>>>>>>>>> help you.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> *Richard Sack *Research Support Manager & Design Engineer
>>>>>>>>> Project Innovation Hub | College of Engineering
>>>>>>>>> John Bardo Center 105
>>>>>>>>> Wichita State University |1845 Fairmount Street Wichita, Kansas 67260
>>>>>>>>> <
>>>>> https://www.google.com/maps/search/1845+Fairmount+Street+Wichita,+Kansas+67260?entry=gmail&source=g
>>>>>>>>> | Box 209
>>>>>>>>> Schedule a meeting
>>>>>>>>> <
>>>>> https://outlook.office.com/bookwithme/user/0dc...@wi...?anonymous&ep=plink
>>>>>>>>> (316) 204-1341
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> *From:* Stuart Stevenson<st...@gm...>
>>>>>>>>> *Sent:* Friday, January 30, 2026 1:10 PM
>>>>>>>>> *To:* Sack, Richard<ric...@wi...>
>>>>>>>>> *Subject:* Small part
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Richard,
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Are you able to print PEEK?
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Thanks
>>>>>>>>>
>>>>>>>>> Stuart
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Addressee is the intended audience.
>>>>>>>>>
>>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>>> read
>>>>>>>>> this email furthermore it is my wish you would close this without
>>>>> saving or
>>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>>> correspondence.
>>>>>>>>>
>>>>>>>>> Thank you for honoring my wish.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Emc-users mailing list
>>>>>>> Emc...@li...
>>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>> Cheers, Gene Heskett, CET.
>>>>>> --
>>>>>> "There are four boxes to be used in defense of liberty:
>>>>>> soap, ballot, jury, and ammo. Please use in that order."
>>>>>> -Ed Howdershelt (Author, 1940)
>>>>>> If we desire respect for the law, we must first make the law
>>>>> respectable.
>>>>>> - Louis D. Brandeis
>>>>>> Don't poison our oceans, interdict drugs at the src.
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> Emc-users mailing list
>>>>>> Emc...@li... <mailto:Emc...@li...
>>>>>>
>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>> _______________________________________________
>>>>> Emc-users mailing list
>>>>> Emc...@li...
>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>>
>>>> --
>>>> Addressee is the intended audience.
>>>> If you are not the addressee then my consent is not given for you to read
>>>> this email furthermore it is my wish you would close this without saving or
>>>> reading, and cease and desist from saving or opening my private
>>>> correspondence.
>>>> Thank you for honoring my wish.
>>>>
>>>>
>> Cheers, Gene Heskett, CET.
>> -- 
>> "There are four boxes to be used in defense of liberty:
>> soap, ballot, jury, and ammo. Please use in that order."
>> -Ed Howdershelt (Author, 1940)
>> If we desire respect for the law, we must first make the law respectable.
>> - Louis D. Brandeis
>> Don't poison our oceans, interdict drugs at the src.
>>
>>
>>
>>
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li... <mailto:Emc...@li...>
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Cheers, Gene Heskett, CET.
-- 
"There are four boxes to be used in defense of liberty:
  soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
  - Louis D. Brandeis
Don't poison our oceans, interdict drugs at the src.

Re: [Emc-users] Small part

[Dave E. <den...@ch...>]

Many years ago I had pretty good luck with epoxy catalyzed with  trimellitic anhydride
The epoxy was a bright yellow and was used to seal cartridge heaters in a reactor operating at a couple of atm with a charge of water and powdered zinc. But then that was 60+ years ago, YMMV.
IOW Good luck. 

Dave

Note for the curious: the idea was to recover the hydrogen from the water and
 then convert it to methane and count the amt of tritium in the methane. Tritium has a pretty short half-life so much easier to count and get good counting statistics than C14. Don’t think we were ever even close to successful. 



 On Jan 31, 2026, at 3:48 PM, gene heskett <ghe...@sh...> wrote:
> 
> On 1/31/26 17:58, Stuart Stevenson wrote:
>> LinuxCNC guys,
>>  I don't know how I included LinuxCNC guys in this email. It must have been
>> me trying to reply to an email using my Iphone. I literally hate it. It
>> updates as it wishes. The updates modify anything Apple wants to. I have to
>> be constantly relearning most everything. I feel like I am using a hatchet
>> with the sharp side cut off. When you cut the sharp side off a hatchet, you
>> end up with a hammer.
>> 
>>  I have an automotive radiator to repair. The part is plastic. I have two
>> 3D printers, neither enclosed. The motor was extremely overheated by
>> running out of coolant. Fortunately(I think 🤣), it still runs good. Shows
>> no sigh of damage except of the pressure ring in the filler neck is eroded
>> away. Using testing liquid I detect no presence of exhaust gases in the
>> coolant and the exhaust system looks clean.
>>  Researching what plastic to print I chose PEEK because of the high glass
>> transition temperature - ~140C. I asked Richard at Wichita State Univeristy
>> if he could print PEEK. Richard does amazing things. He doesn't have a
>> printer that will print PEEK. Richards reply introduced me to Chris
>> Rempe(also at WSU). He has a printer that will print Ultim 1010. Ultim 1010
>> has a higher glass transition temperature, so I replied to ask him if he
>> could do it.
>>  Somehow, I included you guys. I haven't heard from Chis Rempe, but this
>> project will probably become a radiator replacement as a new radiator from
>> RockAuto is USD85.00 up to USD125.00 plus shipping.
>>  This car belongs to my sister-in-law. I was hoping for a quick little
>> 'magic' repair. Heh, not likely.
> Sorry Stuart, but at a 140C glass temp and 15 to 20 psi pressure
> I don't think even PEEK is a long term solution.  I've bought some
> stuff from Rock Auto in the past. Everything fit.  But I quite buying
> used vehicles with fogged up headlights.
> 
> I share your views on govmnt and hell phones. I have one, but
> since I've been 99% retired for 23 years now, just some occasional
> consulting with our local daytime AM'er, I let the sim card expire
> about 9 years ago. I miss it like a broken leg.  If I ever get the urge
> to make the grand tour west of the river to see my 4  boys again I
> might see about a new card. But at 91, macular degeneration
> is spoiling my enjoyment for driving the length of SD at WOT & 3 AM.
> 
> Take care of #1.
>> I love the LinuxCNC community!
> Proving forever that you are "one of us".  Thank you.
>> 
>> Regards,
>> Stuart
>> 
>> 
>> On Sat, Jan 31, 2026 at 4:11 PM Stuart Stevenson <st...@gm...> wrote:
>> 
>>> LOL! Andy,
>>> 
>>>  I have that on there only to screw with government snoops. I don't expect
>>> them to honor it. For one thing, they must have some honor to begin with
>>> before they try to use it.
>>> 
>>> On Sat, Jan 31, 2026 at 12:54 PM Chris Albertson <
>>> alb...@gm...> wrote:
>>> 
>>>> 
>>>> Plan on a 360–450°C hot end, 120–160°C bed, and a fully enclosed,
>>>> actively heated chamber (70–150°C).       But general guidelines are not
>>>> enough.  It depends on the exact brand of filament and your own testing.
>>>> 
>>>> The best bed heater is dirt-cheap.   You put direct mains AC on the
>>>> heater and control it with a contractor that is designed for water heaters
>>>> or electric home heating.   Same for the enclosure heat.   You need
>>>> insulation on the enclosure; plexiglass will not be enough, the ceramic
>>>> felt used on stoves works.
>>>> 
>>>> A cheaper solution is to re-engineer your product so that it does not
>>>> require PEEK.
>>>> 
>>>> OK, you can’t redesign the part?  You can send it out to a commercial
>>>> printer.      But then, “why PEEK?” have them print it in stainless steel.
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>>> On Jan 31, 2026, at 4:44 AM, gene heskett <ghe...@sh...> wrote:
>>>>> 
>>>>> On 1/30/26 23:22, Stuart Stevenson wrote:
>>>>>> Addressee is the intended audience.1 mm
>>>>>> If you are not the addressee then my consent is not given for you to
>>>> read
>>>>>> this email furthermore it is my wish you would close this without
>>>> saving or
>>>>>> reading, and cease and desist from saving or opening my private
>>>>>> correspondence.
>>>>>> Thank you for honoring my wish.
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> ---------- Forwarded message ---------
>>>>>> From: Stuart Stevenson<st...@gm...>
>>>>>> Date: Fri, Jan 30, 2026 at 10:06 PM
>>>>>> Subject: Re: Small part
>>>>>> To: Sack, Richard<ric...@wi...>
>>>>>> CC: Chris Rempe<chr...@id...>
>>>>>> 
>>>>>> 
>>>>>> Chris, are you able to consider a part from a private individual? I
>>>> have a
>>>>>> single small PEEK part. Ultim 1010 would be a little better. It is a
>>>> repair
>>>>>> part for an automotive radiator. I can supply a solid model and/or an
>>>> STL
>>>>>> file.
>>>>> Stuart:
>>>>> What sort of temps are needed for PEEK? I have what I thought was a
>>>> comprehensive chart of such, but it doesn't have a reference for PEEK.
>>>> Apparently the composer of this chart wasn't concerned with materials
>>>> needing more than 300C nozzles. Even that is getting pretty far into the
>>>> far end of heater lifetimes mortality curve. I do some PC, but even at 285C
>>>> I'm losing heaters in 100-150 hrs. That also needs a bed temp around 100C,
>>>> well beyond most under $1500 printers. The printer I've rebuilt to do that,
>>>> an Ender 5 Plus now has 72 volt closed loop stepper/servo XY motors, and a
>>>> 36 volt bed supply that an get to 125C. I also have a Sovol sv08 MAX. Which
>>>> is acting like its going to be my next fav printer. Either one warms up a
>>>> 15 amp breaker in the service.
>>>>>> Thanks
>>>>>> Stuart Stevenson
>>>>>> 4638 Farmstead Ct
>>>>>> Bel Aire, Ks 67220-1617
>>>>>> 316-258-0953
>>>>>> st...@gm...
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> Addressee is the intended audience.
>>>>>> If you are not the addressee then my consent is not given for you to
>>>> read
>>>>>> this email furthermore it is my wish you would close this without
>>>> saving or
>>>>>> reading, and cease and desist from saving or opening my private
>>>>>> correspondence.
>>>>>> Thank you for honoring my wish.
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> On Fri, Jan 30, 2026 at 9:49 PM Stuart Stevenson<st...@gm...>
>>>> wrote:
>>>>>>> Thank you.
>>>>>>> 
>>>>>>> 
>>>>>>> Addressee is the intended audience.
>>>>>>> If you are not the addressee then my consent is not given for you to
>>>> read
>>>>>>> this email furthermore it is my wish you would close this without
>>>> saving or
>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>> correspondence.
>>>>>>> Thank you for honoring my wish.
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> On Fri, Jan 30, 2026 at 3:26 PM Sack, Richard<
>>>> ric...@wi...>
>>>>>>> wrote:
>>>>>>> 
>>>>>>>> I am unable to print PEEK.
>>>>>>>> 
>>>>>>>> PEEK needs a very high temperature nozzle, very hot build chamber,
>>>> etc.
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Chris Rempe has fancy and very expensive 3D printers; he may be able
>>>> to
>>>>>>>> help you.
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> *Richard Sack *Research Support Manager & Design Engineer
>>>>>>>> Project Innovation Hub | College of Engineering
>>>>>>>> John Bardo Center 105
>>>>>>>> Wichita State University |1845 Fairmount Street Wichita, Kansas 67260
>>>>>>>> <
>>>> https://www.google.com/maps/search/1845+Fairmount+Street+Wichita,+Kansas+67260?entry=gmail&source=g
>>>>>>>> | Box 209
>>>>>>>> Schedule a meeting
>>>>>>>> <
>>>> https://outlook.office.com/bookwithme/user/0dc...@wi...?anonymous&ep=plink
>>>>>>>> (316) 204-1341
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> *From:* Stuart Stevenson<st...@gm...>
>>>>>>>> *Sent:* Friday, January 30, 2026 1:10 PM
>>>>>>>> *To:* Sack, Richard<ric...@wi...>
>>>>>>>> *Subject:* Small part
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Richard,
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Are you able to print PEEK?
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Thanks
>>>>>>>> 
>>>>>>>> Stuart
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>>>> Addressee is the intended audience.
>>>>>>>> 
>>>>>>>> If you are not the addressee then my consent is not given for you to
>>>> read
>>>>>>>> this email furthermore it is my wish you would close this without
>>>> saving or
>>>>>>>> reading, and cease and desist from saving or opening my private
>>>>>>>> correspondence.
>>>>>>>> 
>>>>>>>> Thank you for honoring my wish.
>>>>>>>> 
>>>>>>>> 
>>>>>>>> 
>>>>>> _______________________________________________
>>>>>> Emc-users mailing list
>>>>>> Emc...@li...
>>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>>> Cheers, Gene Heskett, CET.
>>>>> --
>>>>> "There are four boxes to be used in defense of liberty:
>>>>> soap, ballot, jury, and ammo. Please use in that order."
>>>>> -Ed Howdershelt (Author, 1940)
>>>>> If we desire respect for the law, we must first make the law
>>>> respectable.
>>>>> - Louis D. Brandeis
>>>>> Don't poison our oceans, interdict drugs at the src.
>>>>> 
>>>>> 
>>>>> _______________________________________________
>>>>> Emc-users mailing list
>>>>> Emc...@li... <mailto:Emc...@li...
>>>>> 
>>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>> 
>>>> _______________________________________________
>>>> Emc-users mailing list
>>>> Emc...@li...
>>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>> 
>>> 
>>> --
>>> Addressee is the intended audience.
>>> If you are not the addressee then my consent is not given for you to read
>>> this email furthermore it is my wish you would close this without saving or
>>> reading, and cease and desist from saving or opening my private
>>> correspondence.
>>> Thank you for honoring my wish.
>>> 
>>> 
> 
> Cheers, Gene Heskett, CET.
> -- 
> "There are four boxes to be used in defense of liberty:
> soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author, 1940)
> If we desire respect for the law, we must first make the law respectable.
> - Louis D. Brandeis
> Don't poison our oceans, interdict drugs at the src.
> 
> 
> 
> 
> _______________________________________________
> Emc-users mailing list
> Emc...@li... <mailto:Emc...@li...>
> https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Unsubscripe

[GARY F. <gf...@co...>]

Unsubscripe

Re: [Emc-users] y axis homes wrong direction

[John D. <jo...@au...>]

Hopefully this information will help.  

I've homed my knee mill.  The limit switches are also used as the home switches.  The knee is all the way down when homed since that's the safest place to go.  Table has moved to the far right and as close as possible to the frame.  
https://autoartisans.com/mill/Mill_Homed_s.jpg

The next photo shows the machine coordinates as 0,0,0 when homed which is where the spindle is.
https://autoartisans.com/mill/Mill_MachineCo_ord_s.jpg

The final photo shows the machine coordinates with table all the way forward which duplicates Cartesian Y as Y gets bigger as the spindle is moved up the graph.  X position gets bigger as you move to the right on the graph or as the spindle is in effect moved to the right.
The Z value is negative because in effect we are moving down below the zero plane even though it's the knee that is moving up.  The value of Z is based on the quill touching a 1-2-3 block set up for 3".  That shows the absolute total distance from the home position to the bottom of the quill is 9.725"+3"=12.725"
https://autoartisans.com/mill/Mill_At_Limits.jpg

In the HAL file the limit switches are defines as follows:
# MESA 7i92H P2 connections
net min-home-x      <= hm2_7i92.0.gpio.014.in
net min-home-y      <= hm2_7i92.0.gpio.015.in
net max-home-z      <= hm2_7i92.0.gpio.016.in
net max-x-y-min-z   <= hm2_7i92.0.gpio.003.in

Notice the Z axis switches are at the other end of the XYZ co-ordinate system and the non-home limit switches are in series so any one closure will cause a motion stoppage on all axis.

Further in the HAL file I have:
net min-home-x => joint.0.home-sw-in
net min-home-x => joint.0.neg-lim-sw-in
net max-x-y-min-z => joint.0.pos-lim-sw-in

net min-home-y => joint.1.home-sw-in
net min-home-y => joint.1.neg-lim-sw-in
net max-x-y-min-z => joint.1.pos-lim-sw-in

net max-home-z => joint.2.home-sw-in
net max-x-y-min-z => joint.2.neg-lim-sw-in
net max-home-z => joint.2.pos-lim-sw-in

Cheers,
John Dammeyer

> -----Original Message-----
> From: Stuart Stevenson [mailto:st...@gm...]
> Sent: April 3, 2026 8:50 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] y axis homes wrong direction
> 
> I always configured my machines with machine zero at the most positive
> position Ie
> facing the machine
> tool position not table position
> X as far right as it will go
> Y as far away as it will go
> Z as far up as it will go
> 
> two reasons, all the WPC offsets were always negative.
>                       zero return is always in the same direction
> Therefore, I didn't have to 'thnk' (remember) "Which way did I configure
> this machine?"
> 
> I did this no matter the control manufacturer. Outside service men were
> sometimes confused but operators quickly adjusted.
> 
> regards
> Stuart
> 
> On Thu, Apr 2, 2026 at 6:48�PM Luca Toniolo <lu...@ai...> wrote:
> 
> > I'm sorry, I just saw what he wrote, Z homes at 4 is wrong, Z should home
> > at 0, and Z works in negative, this is pretty standard, you'll have a lot
> > of headaches if you don't do it that way.
> >
> > On April 3, 2026 7:31:39 AM GMT+08:00, andy pugh
> <bod...@gm...>
> > wrote:
> > >On Thu, 2 Apr 2026 at 23:49, Luca Toniolo <lu...@ai...> wrote:
> > >>
> > >> If your Y plus is toward the back of the machine, and your homing
> > sensor is toward the back of the machine, you home at 30 not at 0.
> > >
> > >It's often better to home to 0 and set the lower limit negative.
> > >LinuxCNC works equally well either way, but some CAM systems make
> > >assumptions.
> > >Admittedly generally with Z. (Fusion 360 CAM will often insert a G53
> > >Z0 as a full retract).
> > >
> > >You need to work out if the axis is reversed entirely, or just the
> > >homing direction.
> > >
> > >The solution might be as simple as specifying negative
> > HOME_SEARCH_VELOCITY
> > >
> > >--
> > >atp
> > >"A motorcycle is a bicycle with a pandemonium attachment and is
> > >designed for the especial use of mechanical geniuses, daredevils and
> > >lunatics."
> > >� George Fitch, Atlanta Constitution Newspaper, 1912
> > >
> > >
> > >_______________________________________________
> > >Emc-users mailing list
> > >Emc...@li...
> > >https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> > _______________________________________________
> > Emc-users mailing list
> > Emc...@li...
> > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> 
> 
> --
> Addressee is the intended audience.
> If you are not the addressee then my consent is not given for you to read
> this email furthermore it is my wish you would close this without saving or
> reading, and cease and desist from saving or opening my private
> correspondence.
> Thank you for honoring my wish.
> 
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] y axis homes wrong direction

[Stuart S. <st...@gm...>]

I always configured my machines with machine zero at the most positive
position Ie
facing the machine
tool position not table position
X as far right as it will go
Y as far away as it will go
Z as far up as it will go

two reasons, all the WPC offsets were always negative.
                      zero return is always in the same direction
Therefore, I didn't have to 'thnk' (remember) "Which way did I configure
this machine?"

I did this no matter the control manufacturer. Outside service men were
sometimes confused but operators quickly adjusted.

regards
Stuart

On Thu, Apr 2, 2026 at 6:48 PM Luca Toniolo <lu...@ai...> wrote:

> I'm sorry, I just saw what he wrote, Z homes at 4 is wrong, Z should home
> at 0, and Z works in negative, this is pretty standard, you'll have a lot
> of headaches if you don't do it that way.
>
> On April 3, 2026 7:31:39 AM GMT+08:00, andy pugh <bod...@gm...>
> wrote:
> >On Thu, 2 Apr 2026 at 23:49, Luca Toniolo <lu...@ai...> wrote:
> >>
> >> If your Y plus is toward the back of the machine, and your homing
> sensor is toward the back of the machine, you home at 30 not at 0.
> >
> >It's often better to home to 0 and set the lower limit negative.
> >LinuxCNC works equally well either way, but some CAM systems make
> >assumptions.
> >Admittedly generally with Z. (Fusion 360 CAM will often insert a G53
> >Z0 as a full retract).
> >
> >You need to work out if the axis is reversed entirely, or just the
> >homing direction.
> >
> >The solution might be as simple as specifying negative
> HOME_SEARCH_VELOCITY
> >
> >--
> >atp
> >"A motorcycle is a bicycle with a pandemonium attachment and is
> >designed for the especial use of mechanical geniuses, daredevils and
> >lunatics."
> >— George Fitch, Atlanta Constitution Newspaper, 1912
> >
> >
> >_______________________________________________
> >Emc-users mailing list
> >Emc...@li...
> >https://lists.sourceforge.net/lists/listinfo/emc-users
>
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users
>


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Re: [Emc-users] y axis homes wrong direction

[Luca T. <lu...@ai...>]

I'm sorry, I just saw what he wrote, Z homes at 4 is wrong, Z should home at 0, and Z works in negative, this is pretty standard, you'll have a lot of headaches if you don't do it that way.

On April 3, 2026 7:31:39 AM GMT+08:00, andy pugh <bod...@gm...> wrote:
>On Thu, 2 Apr 2026 at 23:49, Luca Toniolo <lu...@ai...> wrote:
>>
>> If your Y plus is toward the back of the machine, and your homing sensor is toward the back of the machine, you home at 30 not at 0.
>
>It's often better to home to 0 and set the lower limit negative.
>LinuxCNC works equally well either way, but some CAM systems make
>assumptions.
>Admittedly generally with Z. (Fusion 360 CAM will often insert a G53
>Z0 as a full retract).
>
>You need to work out if the axis is reversed entirely, or just the
>homing direction.
>
>The solution might be as simple as specifying negative HOME_SEARCH_VELOCITY
>
>-- 
>atp
>"A motorcycle is a bicycle with a pandemonium attachment and is
>designed for the especial use of mechanical geniuses, daredevils and
>lunatics."
>— George Fitch, Atlanta Constitution Newspaper, 1912
>
>
>_______________________________________________
>Emc-users mailing list
>Emc...@li...
>https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] y axis homes wrong direction

[Luca T. <lu...@ai...>]

Negative search vel, homes at the front Y0, sensor must be reading when machine is at the front, the back is Y30. This is one of the alternative I proposed, it really depends on what type of machine it is, I think his sensor is at the back, if he put it there, should be reasonable to assume he wants the machine to home at the back for some reason, and if you want to work with Y positive values, you will home at 30 not 0, I think I gave all possible alternatives already. I don't think there is a standard correct way of doing this. Inverting Y direction is the most horrible one to me, but I have seen it, more often than I'd like.

On April 3, 2026 7:31:39 AM GMT+08:00, andy pugh <bod...@gm...> wrote:
>On Thu, 2 Apr 2026 at 23:49, Luca Toniolo <lu...@ai...> wrote:
>>
>> If your Y plus is toward the back of the machine, and your homing sensor is toward the back of the machine, you home at 30 not at 0.
>
>It's often better to home to 0 and set the lower limit negative.
>LinuxCNC works equally well either way, but some CAM systems make
>assumptions.
>Admittedly generally with Z. (Fusion 360 CAM will often insert a G53
>Z0 as a full retract).
>
>You need to work out if the axis is reversed entirely, or just the
>homing direction.
>
>The solution might be as simple as specifying negative HOME_SEARCH_VELOCITY
>
>-- 
>atp
>"A motorcycle is a bicycle with a pandemonium attachment and is
>designed for the especial use of mechanical geniuses, daredevils and
>lunatics."
>— George Fitch, Atlanta Constitution Newspaper, 1912
>
>
>_______________________________________________
>Emc-users mailing list
>Emc...@li...
>https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] y axis homes wrong direction

[andy p. <bod...@gm...>]

On Thu, 2 Apr 2026 at 23:49, Luca Toniolo <lu...@ai...> wrote:
>
> If your Y plus is toward the back of the machine, and your homing sensor is toward the back of the machine, you home at 30 not at 0.

It's often better to home to 0 and set the lower limit negative.
LinuxCNC works equally well either way, but some CAM systems make
assumptions.
Admittedly generally with Z. (Fusion 360 CAM will often insert a G53
Z0 as a full retract).

You need to work out if the axis is reversed entirely, or just the
homing direction.

The solution might be as simple as specifying negative HOME_SEARCH_VELOCITY

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1912

Re: [Emc-users] y axis homes wrong direction

[Luca T. <lu...@ai...>]

If your Y plus is toward the back of the machine, and your homing sensor is toward the back of the machine, you home at 30 not at 0.
your HOME_OFFSET will be 30.1
HOME will be 30
HOME_SEARCH_VEL must be positive 
Alternative like Z your Y works in negative if you home at 0 at the back
Alternative you home to the front at 0
Alternative your Y reverse your Y from normal Cartesian, but this breaks a bit of everything fcode compatibility wise everything is mirrored, but most cam have mirror Y function I believe.


On April 3, 2026 5:01:06 AM GMT+08:00, Nicklas SB Karlsson <nk...@nk...> wrote:
>Tried it and starting at wrong side of the home swith of course start to home in wrong direction. It also continue in
>same direction then it hit limit switch even though it should be possible to conclude it is now heading in wrong
>direction.
>
>Nicklas Karlsson
>
>
>tor 2026-04-02 klockan 03:33 -0400 skrev dfa...@dv...:
>> 
>>         
>> 
>> 
>> Greetings - I recently downloaded the latest version of LinuxCNC and installed it on my 30"x30" cnc machine that has a
>> 20W laser.
>> 
>> I have a parallel port that runs to a parallel port breakout board.  There is a home switch on each axis, whose
>> operation if visible via led indicators on the breakout board.  The Z axis homes at location 4.000, the X and Y axis
>> home at 0.000.  The Z axis homes, the X axis homes, but the Y axis refuses to move toward 0.000 when homing.
>> 
>> I have tried changing the sign on Scaling in the ini (or is it the hal file) and the axis does move in the correct
>> direction using the manual move buttons in LinuxCNC.  I have home set at 0.000, min limit a -1.000, max limit at
>> 30.000".  The led indicator is off unless the home switch is pressed - just like the Z & X axis.
>> 
>> I am out of ideas and would appreciate some guidance.
>> Kind regards,
>> David
>>  
>> 
>> David V. Fansler
>> S/V Dragon Fire
>> S/V Spirit of 76
>> www.dv-fansler.com
>> dfa...@dv...
>> YouTube "Sailing Solo at 70"
>> 
>> 
>> 
>> 
>> 
>> _______________________________________________
>> Emc-users mailing list
>> Emc...@li...
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
>
>
>_______________________________________________
>Emc-users mailing list
>Emc...@li...
>https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] y axis homes wrong direction

[Nicklas SB K. <nk...@nk...>]

Tried it and starting at wrong side of the home swith of course start to home in wrong direction. It also continue in
same direction then it hit limit switch even though it should be possible to conclude it is now heading in wrong
direction.

Nicklas Karlsson


tor 2026-04-02 klockan 03:33 -0400 skrev dfa...@dv...:
> 
>         
> 
> 
> Greetings - I recently downloaded the latest version of LinuxCNC and installed it on my 30"x30" cnc machine that has a
> 20W laser.
> 
> I have a parallel port that runs to a parallel port breakout board.  There is a home switch on each axis, whose
> operation if visible via led indicators on the breakout board.  The Z axis homes at location 4.000, the X and Y axis
> home at 0.000.  The Z axis homes, the X axis homes, but the Y axis refuses to move toward 0.000 when homing.
> 
> I have tried changing the sign on Scaling in the ini (or is it the hal file) and the axis does move in the correct
> direction using the manual move buttons in LinuxCNC.  I have home set at 0.000, min limit a -1.000, max limit at
> 30.000".  The led indicator is off unless the home switch is pressed - just like the Z & X axis.
> 
> I am out of ideas and would appreciate some guidance.
> Kind regards,
> David
>  
> 
> David V. Fansler
> S/V Dragon Fire
> S/V Spirit of 76
> www.dv-fansler.com
> dfa...@dv...
> YouTube "Sailing Solo at 70"
> 
> 
> 
> 
> 
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] y axis homes wrong direction

[Luca T. <lu...@ai...>]

Homing is done according to

HOME_SEARCH_VEL
And
HOME_LATCH_VEL
Also to check the 
HOME_SEQUENCE

Check the docs, incredibly insightful 

<https://linuxcnc.org/docs/html/config/ini-homing.html#sec:homing-section>



On April 2, 2026 3:33:51 PM GMT+08:00, dfa...@dv... wrote:
>
>	
>
>
>Greetings - I recently downloaded the latest version of LinuxCNC and installed it on my 30"x30" cnc machine that has a 20W laser.
>
>I have a parallel port that runs to a parallel port breakout board.  There is a home switch on each axis, whose operation if visible via led indicators on the breakout board.  The Z axis homes at location 4.000, the X and Y axis home at 0.000.  The Z axis homes, the X axis homes, but the Y axis refuses to move toward 0.000 when homing.
>
>I have tried changing the sign on Scaling in the ini (or is it the hal file) and the axis does move in the correct direction using the manual move buttons in LinuxCNC.  I have home set at 0.000, min limit a -1.000, max limit at 30.000".  The led indicator is off unless the home switch is pressed - just like the Z & X axis.
>
>I am out of ideas and would appreciate some guidance.
>Kind regards,
>David
> 
>
>David V. Fansler
>S/V Dragon Fire
>S/V Spirit of 76
>www.dv-fansler.com
>dfa...@dv...
>YouTube "Sailing Solo at 70"
>
>
>
>
>
>_______________________________________________
>Emc-users mailing list
>Emc...@li...
>https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] y axis homes wrong direction

[cg <f1...@fr...>]

Hi David,

Just an idea: do you use stepping motors? Did you try to swap one phase (and only one)?

Best,
Christian

> Le 2 avr. 2026 à 09:33, dfa...@dv... a écrit :
> 
> 
> 	
> 
> 
> Greetings - I recently downloaded the latest version of LinuxCNC and installed it on my 30"x30" cnc machine that has a 20W laser.
> 
> I have a parallel port that runs to a parallel port breakout board.  There is a home switch on each axis, whose operation if visible via led indicators on the breakout board.  The Z axis homes at location 4.000, the X and Y axis home at 0.000.  The Z axis homes, the X axis homes, but the Y axis refuses to move toward 0.000 when homing.
> 
> I have tried changing the sign on Scaling in the ini (or is it the hal file) and the axis does move in the correct direction using the manual move buttons in LinuxCNC.  I have home set at 0.000, min limit a -1.000, max limit at 30.000".  The led indicator is off unless the home switch is pressed - just like the Z & X axis.
> 
> I am out of ideas and would appreciate some guidance.
> Kind regards,
> David
>  
> 
> David V. Fansler
> S/V Dragon Fire
> S/V Spirit of 76
> www.dv-fansler.com
> dfa...@dv...
> YouTube "Sailing Solo at 70"
> 
> 
> 
> 
> 
> _______________________________________________
> Emc-users mailing list
> Emc...@li...
> https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] y axis homes wrong direction

[<dfa...@dv...>]

	


Greetings - I recently downloaded the latest version of LinuxCNC and installed it on my 30"x30" cnc machine that has a 20W laser.

I have a parallel port that runs to a parallel port breakout board.  There is a home switch on each axis, whose operation if visible via led indicators on the breakout board.  The Z axis homes at location 4.000, the X and Y axis home at 0.000.  The Z axis homes, the X axis homes, but the Y axis refuses to move toward 0.000 when homing.

I have tried changing the sign on Scaling in the ini (or is it the hal file) and the axis does move in the correct direction using the manual move buttons in LinuxCNC.  I have home set at 0.000, min limit a -1.000, max limit at 30.000".  The led indicator is off unless the home switch is pressed - just like the Z & X axis.

I am out of ideas and would appreciate some guidance.
Kind regards,
David
 

David V. Fansler
S/V Dragon Fire
S/V Spirit of 76
www.dv-fansler.com
dfa...@dv...
YouTube "Sailing Solo at 70"

Re: [Emc-users] Forum down

[Luca T. <lu...@ai...>]

Yes, the forum goes down around this time, it was up a few hours ago

On April 2, 2026 3:22:15 PM GMT+08:00, Thomas J Powderly <tj...@gm...> wrote:
>Hello,
>
>https://forum.linuxcnc.org
>
>has timed out for  2 days
>
>Is the url correct?
>
>Thx
>
>To,P4
>
>
>
>_______________________________________________
>Emc-users mailing list
>Emc...@li...
>https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Forum down

[Thomas J P. <tj...@gm...>]

Hello,

https://forum.linuxcnc.org

has timed out for  2 days

Is the url correct?

Thx

To,P4

[Emc-users] Forum down

[Thomas J P. <tj...@gm...>]

https://forum.linuxcnc.org/

times out from 10am till 7pm (in Thailand)

connection times out

I could not access yesterday..

TomP