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Old 11-21-2020, 02:56 PM
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BEC BEC is offline
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Join Date: Feb 2009
Location: Auburn, Washington
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I concur with 5x7 on all (albeit with a better success rate on Estes igniters/starters old and new). I personally haven’t had as many issues with the current Estes “starters” as many report. Installation with them, however, is critical. That said, clay in the motor nozzle will defeat even a nicely-energetic older igniter that is properly installed. I would think this situation really couldn’t even occur the way Q-Jets are made.

But his last point - that spares are supplied by Estes - is important. Two-packs (24mm motors) and four-packs (13mm motors) only come with one per motor, but three packs (18mm motors) and bulk boxes come with extras, so over time one builds up a supply of spares and that makes a particular failure less of an issue. And it’s why I found FirstFire Micros sold separately I bought for spares that arrived broken or otherwise damaged particularly irritating, especially since they’re over $1 a piece even when sold at a steep discount.

Also, because of the fragility of the FirstFire Micro and the fairly large gap between the nozzle and the slot in the grain where it needs to go on B and especially A impulse motors, inexperienced people are going to have a rather higher failure rate than I’ve had myself (two in all the Q-Jets I have flown so far, so probably less than 1% failure). If you stick the initiator in the nozzle and it’s not nice and straight (not well straightened from the bent-in-half state as they are provided in the two packs) and you know to aim for the center and have a bit of an idea what to feel for/what correct installation looks like, it seems to me that initiators fired below the propellant grain or against the bottom if it will be relatively common if, say, a Cub Scout pack is using a bulk box of A3-4FJs rather than Estes A8-3s in their Wizards or Vikings or Alphas or Generic E2Xs. I am not sure what you can do about that, really, though other than hope that the leaders and/or the clubs providing launch services know how to do it right and can teach the kids.
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