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Coilgun with car audio capacitors

  1. Dec 17, 2014 #1
    Hi guys, I'm new to this forum and I just started working on my first coilgun. I've watched several tutorials on how to build a coilgun but all the capacitors they use in the coilguns are electrolytic capacitors. The capacitors don't deliver as much energy as the car audio capacitors. I'm wondering if it is possible to use car audio capacitors in my coilgun and if it is possible how i should build my coilgun. I've planned to use five 5F 24V car audio capacitors as I can buy them in Myanmar and electrolytic capacitors are extremely rare and expensive in Myanmar. Please give me suggestions on how to build a coilgun or railgun out of these car audio capacitors.
  2. jcsd
  3. Dec 17, 2014 #2


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    Capacitors have some limits on the current you can get from them. I don't know how much current you get out of your car audio capacitors.
  4. Dec 17, 2014 #3
    Even if you didn't have current limits on the capacitor, you'd still have to contend with the capacitor discharge equation: I = V/R*exp(-t/RC).

    I thought about building a coilgun with car audio caps before, and I don't see why it can't work. It might be hard on the cap simply because they're not designed to fully discharge all the time. Just be careful charging them up because you're not supposed to just hook them up directly to a 24V source. You have to slowly charge them to avoid arcing across the terminals.
  5. Dec 17, 2014 #4


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    Staff: Mentor

    We don't discuss dangerous activities here. Thread is closed.
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