#4 UNF or custom threads????

[Goatofmendez]

How can you create custom threads? e.g. ones not on your list? example [1/2 UNF 20 TPI]

thanks

[stephanbrunker]

First, UNF 1/2 - 20 TPI is on the list (spec #11 is UNF). I should change the names to make that more obvious. If you are working within these specifications, the fields for diameter (in inch fractions) and pitch are open for editing, so you can change that.

[Goatofmendez]

Great thanks - I see UNF now.
Regarding custom threads - I have an M10x75 fine metric thread and the code produced created the inner diameter x as x8.81 e.g -> [G76 p0.75 r9.931 x8.81 h0.177 i29.5 k6.641 z-15.0 l360 q1]

However the bolt is for an existing nut and 8.81 is loose - in mach3 it is set for 8.95 to create a tighter fit. Can i simply change this in the output code? e.g -> [G76 p0.75 r9.931 x8.95 h0.177 i29.5 k6.641 z-15.0 l360 q1]

thanks
Steve

[stephanbrunker]

You can either change that in the output code - that is the x value. Because existing nuts are normally within the specs, that means your tool is not 100% perfectly calibrated, so I usually change that in the tooltable. In this case, it would be interesting to measure the pitch diameter what you've cut on your bolt. But really, my program just takes the tables of the specs and calculate from there the x values, regarding the tip form of the tool, so you are free to change the x value.

[Goatofmendez]

Hi, the nut is definitely out of spec, I had them checked. However I cannot change the nut (welded into part) So I have to change my thread slightly to accomodate. Changing the x value will be fine. I already do this in mach3 and it works fine.

thanks

[stephanbrunker]

I just put 0.30v4 online, where the naming of the UNF and UNEF threads in the dropdown is fixed.