Some of the most enjoyable projects tend to have the terrible drawback of also having the most potential to cause bodily harm, like getting zapped by the capacitor when digging into a disposable camera. But often — if you’re careful — this curiosity pays off and you wind up learning how to make something cool like this coil gun from a camera flash’s capacitor. This handheld launches a small nail, and is packed in a handheld form factor with a light switch trigger.
[LabRatMatt] dispels any illusions of potential harm upfront and then repeatedly urges caution throughout his detailed guide. He breaks down the physics at work while maintaining a lighthearted tone. This coil gun uses a capacitor and charging circuit ripped from a disposable camera — [LabRatMatt] decided to double up with another capacitor that he had on hand from a previous project. The coil was repurposed from an old doorbell, but make sure to use a few hundred windings if you make your own coil. A light switch ended up being suitable for a trigger since it is able to handle the voltage spikes.
When assembled, it almost looks like something you’d expect to see in a post-apocalyptic wasteland, but it works!
http://www.youtube.com/watch?v=w_DUDISER6Y
Hackaday has you covered for a variety of DIY weapon projects — everything from a Tesla Coil gun to workplace artillery — but stresses safety in every build you undertake. Beyond that, learn and enjoy!
My undergrad advisor / EE professor built a variant of these with us in his honors seminar.
A small SCR would do the switching more efficiently – the switch sparks over a little and wastes energy.
Another fun version is a washer gun – I did that as a kid. The magnetic field gets more purchase on a flat steel washer than a long nail, so it goes a lot further. You just need to wind a coil in a slot shape.
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Very cool. If this was 1999. Back when you could go to any photo lab and just ask for a bag of the used ones.
Do people still buy disposable cameras anymore? You could get a digital camera for about the same price.
I was at a wedding about 2 years ago and they had a disposable camera at every table for guests to take pictures, I thought then I hadn’t seen them in years. So I do think you can still get them just a little rare. As for processing I would think you could send the film off to the Internet and get some pictures back in the post.
I walked into a CVS in 2011 and asked to buy some used disposable cameras. After looking at me weird, they gave me two for free.
I think there’s a tourist attraction that has them, a pioneer village or something, they re-enact how people used them for pictures long ago… ;-)
Now you’d have to click on Amazon and wait a few hours…much more difficult.
We always stress safety… To infinity and beyond!… To quote a famous space ranger… Arrr arrr arrr.
You could probably get a MUCH beefier strobe circuit from a Vivitar 283 or similar hotshoe flash from a thrift shop. At full power they look a bit like lightning. It can be trouble finding shops that have film stuff coming in though.
Although their caps are very weak by the time they turn up in thrifts usually…. hotshoe flashes in general.
Can’t believe its been almost a year since I published this project! Wish I had published a higher-quality video. Never expected to find my project on hackaday.com! If anyone is still interested, I’ve made an updated video showing a few improvements: https://youtu.be/Xf6eXhK4Ta0