Capacitor to Ignite Estes Igniter?

Using Arduino Project Guidance
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I am building an onboard computer for a rocket. I need to ignite a small Estes motor to light the second stage of the rocket, but I'm having trouble. Estes ignitors take 6v-12v, and I want to minimize the amount of weight the rocket is carrying, so I am trying my best to avoid using an external circuit that the Arduino switches on an off, because that adds a lot more unnecessary weight. My plan was to use a capacitor that I could charge while the rocket launches, and discharge when the altimeter detects a negative change in altitude, but I can't find any simple capacitor circuits, and I don't even know what kind of capacitor I need to use in order to be able to send 6 or more volts to the ignitor. Can anyone give me some insight into where to start with this?

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Got links?

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Sorry, links to what?

4

JoinTheHippies:
Sorry, links to what?

Links to the current the igniters need to operate. They need current, not voltage to generate heat. Batteries need to supply that current.

Why are you putting the batteries in the rocket? At least that is what I gather from the post.

Paul

5

So you want to turn on the second stage motor while your rocket is pointing down?

Sure this could be done with a mini 12v garage door opener battery, but again your describing turning a hobby item into a actual air to ground missle..

Not to mention the ground safety system you need to design so the second stage doesn’t just go off with a local barametric pressure increase..

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Slumpert:
So you want to turn on the second stage motor while your rocket is pointing down?

Sure this could be done with a mini 12v garage door opener battery, but again your describing turning a hobby item into a actual air to ground missle..

Not to mention the ground safety system you need to design so the second stage doesn’t just go off with a local barametric pressure increase..

Ya I tell ya, with a lot of these "secret" projects, IED is the first thing I think of.

7

Estes igniters are intentionally very insensitive, and they’d take a big capacitor to set them off.
While they nominally need 6v, that usually at the other end of 10+ feet of wire, and I suspect these days a relatively small lipo cell with short wires would work fine. Do some experiments...

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Turns out a lithium battery - not a coin cell though - will be just as big or small, and just as light as any capacitor you might require. Actually, smaller and lighter.