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Old 06-06-2021, 09:04 AM
PaulK PaulK is offline
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Join Date: Nov 2005
Location: WI
Posts: 1,847
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Quote:
Originally Posted by LeeR
Paul, anxious to hear how they do. I would prefer to save my remaining Quest Q2G2 igniters for 24mm and 29mm clusters, and use the new Startechs for 18mm clusters.
I flew a bunch of StarTech "starters" yesterday, some with an old 6v Solar Controller, most with my 12v relay controller.

With the 6v Solar Controller, there was a noticeable lag between pressing the button and motor start, though all worked fine, and certainly better than the previous glue-tipped starters. With the 12v system, single motor rockets, they were much better, and started fast.

For my Hydra VII, I soldered all starter leads together, in parallel, to ensure any failure would not be due to poor connections, including some additional "shooter" wire to get all 7 together. This made for a fairly rigid set of starters, unlike the flexibility of 2-wire igniters. All were held in with Estes pink plugs. Motors were 4xB6-0 and 3xC6-5. It was launched with my 12v relay system, which has a ~10AH lead-acid battery, and thick leads from the relay to the pad. Brand new solid copper clips. At launch, there was noticeable lag when pressing the button, unlike 7x Q2G2s or old-style MJG BP motor starters. By sight and sound, it was clear that not all motors started at the same time. I should have taken a high speed video, it seemed like some motors didn't start until nearly off the rod, probably dragging the leads. Still, 6 of 7 motors worked. Post-flight-analysis showed all igniters worked, so my working theory is that the rigid set of starters pulled out before all 7 motors started. With Q2G2s and old-style MJG, the Hydra VII always started instantly and leapt off the pad.

For the next flight, I plan to solder on flexible leads to all 7 starters, to give them more time before they get yanked. Even if this improves reliability, it'll be a pain, and I need to start thinking of alternatives. I don't think the newer MJG starters are a good solution, they're essentially small e-matches, with longer, stiffer wires, more costly, and I doubt they'll fit consistently well in B6/C6 nozzles. I do have quite a stash of solar igniters, it would be interesting to do a side-by-side cluster test between those and StarTech. Since I have 2 Hydra VIIs built, I could do this easily at the same launch. I also need to try smaller clusters.

At this point, though, it doesn't look like I'll be able to use these in place of lower-current starters for large clusters.
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