Home

How to make Coil Gun
Coil Gun:
Coil gun is an instrument that uses electricity to fire magnetic projectiles at a greater velocity. It requires no volatile propellant and can easily be fired at any unlimited time, providing that there is a quantity of bullets. It is composed of following things:
1) Copper Wire
2) Capacitor Bank
3) Transformer
4) DC power source
5) Releasing energy in Capacitors through the coil.
6) Projectile.
When coil gun is fired the coil of the wire induces magnetic field that produce ferromagnetic projectile into the cask. As soon as the projectile reaches the coil magnetic field kept off, allowing the projectile to continue down the cask at high velocities.
Here I will tell you how making a coil gun. Its sibling called rail gun have already been tested in application of the army. It is a strong weapon in defense games. They can be effective in the near future for launching the satellites into orbit.

!(https://a.fsdn.com/con/app/proj/coilgundesign/screenshots/DSC06852.JPG)

How does coil gun work:
It consists of conducting coils which are arranged in series along straight line aside from each other. When current passes through the coils it actuates a magnetic flux through their centers. A ferromagnetic missile comes near to the magnetic field lines created by the coil so it is magnetized and is attracted towards the center of the coil. If we arranged series coil in such a way that the magnetic flux of first coil pulls the missile towards the center after this coil is kept off and second coil gets on which again pulls the missile towards it. As this process is repeated many times through sequence of coils the missile reaches great velocities as it get quicker after passing through each coil. Making coil gun without camera you must keep in your mind that it requires working with great velocities and fast moving missiles. The people who can handle this should make this. I am not responsible for any harm while causing this project. Installation should be done with proper hands to avoid severe injuries.

Materials used in making coil gun:
1) Coated magnet wire
2) PVC pipe
3) 400V full bridge rectifier
4) 100 W incandescent bulb
5) Multimeter
6) Capacitors 400 V, 3300uF.
7) IGBT of 50 A
8) Switches
9) 9 V batteries
10) High gauge wires

Steps for making coil gun:
1) How to prepare coils:
Cut the PVC pipe at 6 cm length. After cutting pipe cover the pipe with installation tape from 1-2 inches of distance around its end. Cover the pipe with installation tape in sequence until it gets thickness of 4-5mm. You have to do the same thing with another 8 cm long PCV pipe.
Now get copper wire and cover it on the pipe with some loose on the beginning. The covering done should be tight and nearer to each other leaving no space between them. After covering first layer then start covering the second layer on top. Copper wires should be covered side to side in the same direction it may be clockwise or anticlockwise. Do this process up to 6-7 layers. If you are using multiple coils then spacing will be 3cm provided. After you have prepared coils use the sandpaper for removing coating to make it conducting.

Make the capacitor charger:
Now use capacitors for this project. Large numbers of capacitors are required. Buy some high voltage capacitors and make a committed charger of them. For making a capacitor bank charger uses the schematic below:

![https://a.fsdn.com/con/app/proj/coilgundesign/screenshots/rectifire.png]

It is a bridge rectifier. Use 600V 20amp bridge rectifier. The positive and negative pin which is shown on chip is provided DC voltage. This positive voltage passes through the incandescent bulb and stand as a high load resistor. Switch is used to change ON/OFF for charging the capacitors. If you are using multiple capacitors select them with same rating and connect them in parallel to increase the rating of current being supplied.

How to make coil gun circulatory:
It has 2 parts

1) Control Part
2) Drive Part

Control Part:

Atmega 8 is used for Control purpose here, it energize the coils in a sequence that first coil energize earlier then the second one. We have used 4n25 optocoupler to make sure the safety of our controller from high voltage spikes.

![https://a.fsdn.com/con/app/proj/coilgundesign/screenshots/Controller.png]
IGBT/Mosfet Driver Part:
Coil 1:
Totem pole configuration is provided to make the impedence less path toward the gate of the mosfet.

![https://a.fsdn.com/con/app/proj/coilgundesign/screenshots/IGBT%20Driver.png]

Coil 2:

In above schematic the coil gun is wired with Mosfet is used to control the high voltage by acting like a switch.Another Mosfet of 50A rated may be used to connect them in parallel providing surge current at rating of 200A. We cannot use relay it burns the contact due to high voltage. The working of Mosfet is so simple when we apply the voltage to gate terminal Mosfet gets on. A microcontroller is used to control the gate voltage which is applied to mosfet and control the current going towards coil act as activation to the coil gun. Large amount of cu wires should be used for connecting capacitors and coil. These connections should be properly installed.

Real Picture of Driver
![https://a.fsdn.com/con/app/proj/coilgundesign/screenshots/DSC06776.JPG]

![https://a.fsdn.com/con/app/proj/coilgundesign/screenshots/IGBT%20Driver.png]

Testing of the coil gun:
The missile used is of the ferromagnetic based object. The bolts having a greater surface area at their heads are functional. Distance and acceleration travelled by missile depend upon the missile you have selected. Spacing provided between coil and bolt is censorious. To find out the functional spacing between them can be found by placing them into the pipe and test the gun. Minimum Spacing should be provided between missile and coil. Gather the pipe through a length of the gun and attach it by using hot glue. The capacitor is tapped on the bottom of a gun and finally put the switch used for triggering on handle after this wire the connections. You may Use the black spray paint to show it in a fuller form. Power magnet used in tiny speakers can be used at one end of the pipe. To grasp the bolt and missile in its place so it does not fall off while we are moving the coil gun.

When I tested the coil gun it was extremely powerful it smashed the box of tin and makes a hole in it. It can penetrate through card boards. So be careful in testing the coil gun use safety precautions and perform it in a right way.
Check the attached video file.