Diy E-match or igniter

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bjphoenix

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Reading about rocket starters there is all kinds of discussion of secret pyrogen recipes, friction sensitivity, regulated materials, etc. I've also read about people dissolving ping pong balls in acetone. I don't want to get into anything questionable, I just need a few igniters for some leftover motors. I found that I can dissolve a bit of smokeless powder in acetone and blob it on the nichrome wire. It dries hard and doesn't seem to be sensitive to friction or impact. It burns about as violently as a wooden match. This seems like the most innocent engine starter that there could be. Am I missing something here? Do some motors require more exotic mixtures to create enough heat for reliability? For my use I would be using these in D through G motors starting with a couple of G Econojets I have left over.
 

Kelly

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What you need for a starter is very dependent on what you are trying to start. Blackpowder is very easy to start. APCP a bit more difficult, some mixtures quite a bit more difficult. Motors with large internal unfilled volume might require enough 'starter' to bring the casing up to operating pressure before the propellant kicks in.
The main use of NC lacquer ("ping pong balls in acetone") is as a binder for other stuff, not as the pyrogen itself. Nichrome wire with an NC dip would be fine for BP motors. Your Econojets might require a bit morethan that, but I don't have a specific recommendation as I've not personally tried that combination.
 
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