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Electric rocket ignition

  1. Aug 1, 2011 #1
    I've been wanting to use capacitors instead of multiple batteries to launch rockets. I also want to see how a capacitor driven ignitor works compared to a normal battery driven with clusters of motors.

    I've been having a couple problems.
    Problem 1:The switch sparks, which I believe causes significant loss of power, but that's just a guess.
    Problem 2: When I use an extremely fine piece of wire it pretty much vaporizes. But when I double up on said wire I don't even get a glow. The vaporizing wire leaves a black trail on paper towel but does not get hot enough to ignite the towel.

    I've seen this on youtube so I know the method works, I just don't know why theirs does well and mine fails.
     
  2. jcsd
  3. Aug 1, 2011 #2
    I don't know how you have your capacitors hooked up, but I have seen a capacitor version of the device to detonate dynamite used in place of the plunger. That device works by double pole, double throw switch with the armature connected to the capacitor. The capacitor has a bleeder resistor in parallel so it won't stay charged long.

    First the switch is thrown to the charge position which charges the capacitor. In this position the battery is connected to the capacitor. When ready to detonate the switch is thrown to the detonate position in which the capacitor is connected to the detonator.

    When you say double up on the wire I assume you mean folding the wire in half and using two strands in parallel. That would halve the resistance and the discharge time. Have you tried using a longer length of a single strand? Having a higher resistance, the wire may not get hot enough to vaporize and would stay hot longer. Having a larger value capacitor may also help.
     
  4. Aug 1, 2011 #3
    Folded the wire in half and twisted it. I will try a longer piece of single strand wire and report the results. I can't change the capacitor out but I can't wire in another one in parallel. I believe that would double the amps since it's an identical cap. But i don't think the circuit was designed to handle it.
     
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