Introduction: DIY: How to Make a Coilgun From Disposable Camera With Flash


This tutorial will show you how to make your own coilgun from disposable camera’s with flash. It looks difficult but it’s easier than you think. I have built this thing for my physics school project and I’m still kind of busy doing research on how to get higher speeds of the projectile. It seemed fun to upload my tutorial with the steps on how to make this dangerous thing!

If you don’t use the optional stuff that is indicated by the ‘what you need’ list, you can build a cheap, portable coilgun! 


Things you’ll need to build this little guy:

-Some disposable camera’s (you can use only one disposable camera)
-A long enameled copper wire of about 0,5mm diameter
-A drinking straw with a length of about 10 cm (choose the length that you prefer)
(you can also use a ballpoint-pen)
-Electrical insulation tape
-Some wire
-Soldering iron
-A light switch
-A push button
-A screwdriver
-A projectile (a small metal object; e.g. a small nail)
-A nice coilgun box (optional)
-Universal circuit board to make your own capacitor bank (optional)
-A voltmeter (optional)
-A black and a red input for the voltmeter (optional)
-Battery holders (optional)
-Stickers to decorate your coilgun box (optional)
-Electronic knowledge & solder skills (optional!)

Assemble the things that you will need and let’s go to the next step!

Step 1: Disassembling Step

The first thing you have to do, is to open the packaging of the disposable camera (of course). When you’re done with it, remove the battery out of the camera. The capacitor might be charged, so watch out!

If you’re afraid to get shocked during disassembling of the camera, just look where the capacitor is and discharge it with a screwdriver. If it gives a nice spark, that’s discharge. You can go further at ease with disassembling.

Disassemble the camera and remove  the flash circuit (carefully).
Look for the charging-button and the flash-button that were used to load en trigger the flash. If you have identified it, mark it and solder the flash-button together, so that it’s closed.

The charging-button is easy to identify (on the circuit that I use). Under your flash circuit, you see an iron button and under it you have two copper plates. Remove that button and mark these two copper plates. Solder each plate with a wire. You will need this later for the light switch.

(Optional step:)
Unsolder the capacitor from each circuit board and solder parallel ( + by the + side and – by the – side ) on a universal circuit board. When you’re done, solder the + and the – side of a capacitor with a wire and reconnect it with the place where the capacitor first at the circuit was. You have made your own capacitor bank!

Step 2: The Coil

Unsolder the flash tube and the reflector attached to it(VERY IMPORTANT!) and mark this place. You will need this later.

I early mentioned in the ‘what you need’ list to use a drinking straw. You wind the enameled copper wire around the drinking straw. (You can also use a ballpoint-pen instead of a drinking straw if you want to waste your beautiful ballpoint-pen. I chose a drinking straw, because it’s cheaper compared to a ballpoint-pen.)

How long the coil will be, is up to you. But I recommend to make a length of about 5 cm.

To get a higher speed with this little guy, you must to work in layers. I have eventually made a coil of 1, 2, 4, 6, 8, 10 and 12 layers.(Yes, I’m insane) I took measurements of the highest speed and the coil of 10 layers won, so I recommend you to wind a coil with 10 layers. Less is also fine, but you will not have the maximum speed of your coilgun. I made about 100 windings in a layer with a length of 5 cm.

Insulating the layers with insulated tape is unnecessary, because the copper wire in already enameled. When you’re done, don’t forget to scrape the coating off the end of your coil. This is important when you’re going to solder the parts.

Step 3: Soldering the Parts

Choose a nice box to put your coilgun in. Make a hole for your light switch, your push button, the led, the coil and two holes for your inputs (optional)

Now you’re ready to solder the parts. Here we go!

You need to solder a wire on each of the copper plates of the previously removed charging button (which you have marked). You need to solder these two wires to the light switch.
With some wires (this entire paragraph), you solder one end of the coil to one connection where the flash tube was before. You solder the other end of the coil to the push button. You solder the other connection of the push button to the other connection of the flash tube connection.

(Optional: )
If you want a voltmeter to measure how high the voltage is when the capacitors are loading, solder the inputs parallel to one of the capacitor of the capacitor bank.
(red input by + and black input by -)

Step 4: Time for Testing

You will now have a nice box with a coilgun in it. Let’s test this monster.

First what you have to do is to is to put the battery in it’s the place as usual. (I’ve solder one battery holder extra so that the coilgun will last longer) Put a small projectile in the coil. Then press on the light switch so the capacitors can load themselves. If you don’t have a voltmeter, the led will give light if the capacitors are loaded. When the led is lighting, turn the light switch off and press the push button. 

Now you’re done!

Have fun with it! If you have any question, just ask me :')

Video at youtube:

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