Show HN: A coilgun I built when I was 16
github.comI made it when I was 15 or 16, so it's nothing amazing—just thought I'd share Cool. I've always wanted to build one. How did you determine the coil sizes, voltages, timing, etc.? Lots of calculations, or just TLAR method? For the coil and yoke, I definitely used the TLAR method (though I did run it through FEMM to see if it would work). For voltage, I just went with the biggest supply I had, and for timing, I simply used a program that estimated the extra time needed after the projectile passed the photo-gate. Keep in mind, I wasn’t very experienced at the time. If I were doing it now, I’d use a random search algorithm to find a coil design that generates the highest force while still switching quickly. For the power supply, I’d use a capacitor bank, and probably stick with similar timing — or possibly use a dedicated capacitor for each stage, charging each differently to deliver longer or shorter pulses as needed