We headed to the park with Em's friend (also a rocketeer) and I was all stoked to launch Thor's Candycane on a D-10 composite motor I got from Apogee. Thor's Candycane is, like his builder, a bit overweight, and can barely get high enough for the parachute to deploy on the biggest black powder (C6) motor his mount will hold.
The composite motor has about three times the ass-kickin' to it, and should make the rocket fly. See also Mr. Creosote. See also ÜberTubester Chixulubster. I have three big rockets with pitiful 18mm motor mounts and these 18mm composite motors are the answer.
So we count down and I hit the button and...
And I mash the button...
I cuss at the button while hitting it and mashing it...
Nothing.
I'd forgotten that the Copperhead ignitors for composite motors take more juice to light than the little Estes controller I had will provide.
There are two solutions to this: only launch your composite motors at club events, using the club's more sophisticated launch control; or get a controller with some attitude.
You can buy them, of course, but they aren't cheap. Better, I was told, to build one.
Except I didn't know how.
And this is where the club comes in. When I got into homebrewing, the single smartest move I made was to joint he Kansas City Biermeisters. In six months I'd gone from an all-extract concentrated wort batch to an all-grain IPA I could really be proud of.
In this case, the KCAR has hooked me up with a whole herd of more accomplished nerds than I.
One such club member, I'll call him Blake because that's his name and he didn't tell me to hide his identity, undertook to teach me how this whole launch control building thing works.
Blake met me at Radio Shack (which was recently demolished by rioting geeks or was being repainted), where he'd already lined up the parts, more or less. After some discussion and further browsing, we changed to a brighter LED light, picked out some different alligator clips, and decided to buy a battery elsewhere.
When we got all the stuff together and got to Blake's apartment, the fun began in earnest.
I've never soldered anything in my life. Ever. And I understand electricity on about the same level I understand women, so Blake was in for a test of his teacherly patience.
To his credit, he didn't get exasperated and give up when it took a good 45 minutes for me to grasp, more or less, the schematic for this project. I won't explain it in technical terms, but basically, a resistor is like a dam that holes the current back; when the switch is pushed, another stream is open, wide open. This is called a short, and the electricity goes chasing the least resistance and lights your rocket motor.
Blake is a pretty serious boost-glider builder, and his fleet includes some astounding creations. A boost glider with a sliding wing so it's rearward under thrust and forward for the recovery, complete with gull wings for a longer flight. Helicopter recovery, he even has a two-stage boost glider, something I'd never even heard of or considered myself.
In the video here, you see an Estes ignitor first, then a Copperhead. Composite motors take more fire to get going, and the ignitors that do that take more juice to make the fire.
It was late when we finished, and the box isn't pretty in some respects, but it works.* Now that I know, more or less, what the thing is all about, maybe I can fix some of that 'not-pretty.' I'll use it as is for awhile to see what else I might want to change on it in the future, though it's a pretty cool box: it benefited from Blake's experiences with the one he'd built awhile back.
*The toggle switch arms it, but you flip it toward you, which seems wrong to me; the wall of the box got a bit melty through a soldering accident; I forgot the grip on one alligator clip before I soldered the lead on, and it was late so I didn't re-do it. Basically, at some point, I'll try to make it look more like I know what I'm doing...
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