In preparation for a series of static tests this week, I’ve been working on some miscellaneous details. I updated the small test stand today to use a load cell for thrust measurement, instead of the state-of-the-art bathroom scale that was previously used, but I’ll talk about that later. I also realized that I’m running horribly short on igniters, and being the cheapskate that I am, I didn’t want to use electric matches for these tests. I remembered reading about using low-watt carbon resistors as igniters somewhere, and a quick Google search confirmed my speculation.

The main theory for resistor igniters is explained in an excellent whitepaper by Bob Dahlquist, archived at Aerocon’s site. I’ve also taken the liberty to put this article into a pretty, portable PDF. Paul Kelly has also done some research using resistors as igniters, archived at Backyard Ballistics. Contrail Rockets also uses a resistive ignition system for their hybrids, so the idea seems to be feasible. I mean, all igniters are resistors in one form or another, right? Granted, I have nichrome and pyrogen. But nichrome is difficult to solder, and bridgewire igniters are quite fiddly to assemble consistently. I wanted something quick, cheap, and brainless.
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