How to Make a Coilgun


Coil guns may sound like futuristic weapons, but they’re actually something you can build at home. They use a current to charge copper wires and create an electromagnet to launch a projectile. To build a coil gun, all you need are a few tools, some wire, and a disposable camera. When you’re finished, you’ll be able to practice shooting a gun you made all by yourself!

Part 1
Taking Apart a Camera Circuit

Taking Apart a Camera Circuit on How to Make a Coilgun

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Remove the paper layer from the disposable camera and locate the tabs on the bottom and sides of the casing. Press down on the tabs with the end of a screwdriver, pulling the case apart while they’re loose. Once all the tabs are released, pull the camera case apart.[1] If the disposable camera doesn’t have tabs, press into the seam on the side of the camera with a flathead screwdriver to force it apart. Ask the photo department at a local drugstore to see if they have used disposable cameras you could use.

Taking Apart a Camera Circuit on How to Make a Coilgun

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Put on rubber gloves before you start working with the components inside the camera. Take out the battery first so that there isn’t a current going through the circuit. Slide your screwdriver underneath the circuit board, and carefully pry it out of the camera.[2] Don’t use your bare hands to take apart your camera since you could get shocked. Tip: Save the camera case so youcan easily mount the circuit foryour coil gun later on.Tip: Save the camera case so you caneasily mount the circuit for your coilgun later on.Tip: Save the camera case so you can easilymount the circuit for your coil gun lateron.Tip: Save the camera case so you can easily mount the circuit for yourcoil gun later on.Tip: Save the camera case so you can easily mount the circuit for your coilgun later on.

Taking Apart a Camera Circuit on How to Make a Coilgun

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The capacitor looks like a black barrel on your circuit board and it stores energy. Make sure the screwdriver you’re using has a rubber-insulated handle. Touch the terminals on the end of the capacitor with the end of your screwdriver to discharge it. The capacitor may spark and make a loud snapping noise when you discharge it.[3] Never touch the terminals on a capacitor with your bare hands since it contains a high voltage. Even when you use an insulated screwdriver, wear rubber gloves as an extra layer of protection.

Taking Apart a Camera Circuit on How to Make a Coilgun

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The flashbulb looks like a clear box and has 3 wires running between it and the circuit board. Use a pair of wire cutters to cut the wires near the capacitor to completely disconnect the flashbulb. Throw the bulb away when you’re finished.[4]

Part 2
Creating the Gun Barrel

Creating the Gun Barrel on How to Make a Coilgun

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Use a basic ballpoint pen that has a cap for the easiest results. Grab the tip of the pen and try pulling it out or unscrewing it from the tube. Remove the ink chamber from inside the pen so you have an empty tube to use as your coil gun’s barrel.[5]Tip: Leave one end of the tubeclosed so your projectiledoesn’t fall out when you loadit.Tip: Leave one end of the tube closedso your projectile doesn’t fall outwhen you load it.Tip: Leave one end of the tube closed soyour projectile doesn’t fall out when youload it.Tip: Leave one end of the tube closed so your projectile doesn’t fallout when you load it.Tip: Leave one end of the tube closed so your projectile doesn’t fall outwhen you load it.

Creating the Gun Barrel on How to Make a Coilgun

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5–5.1 cm) of the tube in a single layer of 30-gauge copper wire. Start your coil about 1⁄2 in (1.3 cm) from the closed end of pen tube. Make sure the coils are tightly wrapped and don’t overlap. Continue wrapping the wire around the pen until 1–2 in (2.5–5.1 cm) are covered with the wire.[6] The copper wire may also be called magnet wire when you buy it from a hardware store. Don’t cut the wire when you’re finished with the first layer since you’ll use it to make additional layers later on.

Creating the Gun Barrel on How to Make a Coilgun

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Once you have your first layer of wires completed, wrap electrical tape around them to hold them in place. Cover all of the wires, but leave the last coil exposed so you can continue wrapping other layers.[7] If you don’t have electrical tape, you can use clear tape or duct tape instead. Make sure there aren’t lumps in the tape or else it will be more difficult to coil the next layer.

Creating the Gun Barrel on How to Make a Coilgun

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Continue using the wire you used for your first layer and coil it back toward your starting point. Make sure the wire is still going in the same direction around the pen or else the gun won’t work. Wrap the wire back and forth, putting electrical tape between each layer, until you’ve completed 7 or 8 layers of wire.[8] You can make more layers of wire if you want, but 7-8 should be enough to shoot a projectile.

Part 3
Wiring the Gun

Wiring the Gun on How to Make a Coilgun

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Take the end of the wire from your coils and cut it so it’s 6 in (15 cm) long. Look for a white stripe or “-” on the capacitor to find the negative terminal. Use a soldering gun to attach the wire to the capacitor. Make sure there’s a solid connection by lightly tugging on the wire.[9] You can buy a soldering gun and solder material from your local hardware store.

Wiring the Gun on How to Make a Coilgun

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Strip 1⁄2 in (1.3 cm) of the insulation off the end of a black wire using wire cutters. Hold the end of the wire next to the positive terminal on your capacitor and use your soldering gun to attach it. Tug it gently once it’s dry to make sure the connection is solid.[10]Tip: Coil the end of the wirearound the terminal before yousolder if you want a more solidconnection. Make sure to wearrubber gloves to prevent anyaccidental shocks.Tip: Coil the end of the wire aroundthe terminal before you solder if youwant a more solid connection. Makesure to wear rubber gloves to preventany accidental shocks.Tip: Coil the end of the wire around theterminal before you solder if you want amore solid connection. Make sure to wearrubber gloves to prevent any accidentalshocks.Tip: Coil the end of the wire around the terminal before you solder ifyou want a more solid connection. Make sure to wear rubber gloves toprevent any accidental shocks.Tip: Coil the end of the wire around the terminal before you solder if youwant a more solid connection. Make sure to wear rubber gloves to prevent anyaccidental shocks.

Wiring the Gun on How to Make a Coilgun

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The switch acts as the trigger for your coil gun. Cut your wire so it extends 3–4 in (7.6–10.2 cm) from your capacitor and strip 1⁄2 in (1.3 cm) of the insulation from the end. Feed the exposed wire into one of the ports on the switch terminal and tighten it in place with a screwdriver.[11] Buy a switch from your local hardware or electronics store.

Wiring the Gun on How to Make a Coilgun

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Cut another black wire so it’s about 3–4 in (7.6–10.2 cm) long. Strip 1⁄2 inch (1.3 cm) of the insulation off both ends of the wire. Feed one end of the wire into the second port on your switch and tighten it in place with a screwdriver. Solder the other end of the wire onto the copper wires on your coil gun to complete the circuit. Make sure your switch is in the off position before soldering it to your coil gun.

Part 4
Shooting the Coil Gun

Shooting the Coil Gun on How to Make a Coilgun

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Cut a 1⁄2–1 in (1.3–2.5 cm) section from a wire hanger if you want a dart-like projectile. Otherwise, you can use a BB or ball bearing as your projectile. Feed the projectile into the barrel of your coil gun.[12] You can use any projectile as long as it’s magnetic.

Shooting the Coil Gun on How to Make a Coilgun

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Place the battery back in its terminal so a current can run through your circuit. Locate the triangular metal piece on the back of the circuit and press down on it with an insulated screwdriver. Hold the screwdriver there for 5 seconds so the capacitor can fully charge.[13] Don’t touch the capacitor after it’s charged or else you will get shocked.

Shooting the Coil Gun on How to Make a Coilgun

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Once the capacitor has been charged, flip the switch into the on position to shoot your gun. Turning on the switch completes the circuit and charges the coils around the barrel, propelling the projectile forward. Once you shoot the gun, leave the switch on for 1 minute so any leftover voltage in the capacitor can discharge safely.[14] Make sure your gun isn’t aimed at any living thing since it will shoot quickly. Tip: Prop up the end of your coilgun’s barrel to shoot yourprojectile farther.Tip: Prop up the end of your coilgun’s barrel to shoot yourprojectile farther.Tip: Prop up the end of your coil gun’sbarrel to shoot your projectile farther.Tip: Prop up the end of your coil gun’s barrel to shoot yourprojectile farther.Tip: Prop up the end of your coil gun’s barrel to shoot your projectilefarther.