ActingLikeAKid
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Interested in input here. I know that a lot of folks use two all-thread rods in their av-bays, but here's what I think I'm going to try - in no small part because this is 38mm ID and 2 rods would take up a lot of room. Picture should explain it mostly, but here's what I have: The transitions (purple) are solid ABS. Plan is to get some 10-32* aluminum allthread. I'll countersink a hole at the bottom of the lower transition that will be just big enough to fit a coupler nut - 10-32 on one side, 1/4" on the other. Drill a hole through the lower transition, screw the allthread into the coupler nut, secure with loctite. Screw a 1/4" eyebolt into the other end, secure with loctite. At the top end of the av-bay**, a coupler nut (also countersunk) screws onto the allthread; I literally can screw that transition on until it's snug. More loctite there. To the top of the coupler nut in the upper transition, I screw a short piece of 10-32 allthread. That gets fillet-glued with Rocketpoxy to a piece of 1/8" birch ply; eggfinder and battery are mounted to that. Ideally the wood is just small enough to fit snugly inside the BT so it won't rattle around. The nose cone and upper BT are glued together and slide over the eggfinder, then are attached with 3 small screws (possibly going into nuts glued into the transition, depending on how fancy I want to be).
I'm wide-open to suggestions on this. I haven't put a TON of thought into how I'd do DD, but like I said in the footnote, this is mostly a placeholder for if I do decide to set up for that later. Mostly I don't want to glue and commit to SD, but I don't like the idea of 2 sets of pins in a fairly long rocket. Please feel free to tell me if I'm doing something stupid and there's a much easier way. The allthread adds 50g or so, probably 50g again for the nuts and the eyebolt. That's less than 10% of the motor-less weight and OpenRocket doesn't say it's an issue for stability (well, it's a bit overstable anyway, so it'll be REALLY stable and may weathercock a bit)
*(I wrote 10/32 some places in the pic and didn't go back to fix it. I'm talking 10-32 screw size, not 10/32")
**(which is not going to house anything right now - this is "for future use" if I want to do DD. Also allthread seemed like a slick way to secure the two transitions - way less wobbly than pins)
I'm wide-open to suggestions on this. I haven't put a TON of thought into how I'd do DD, but like I said in the footnote, this is mostly a placeholder for if I do decide to set up for that later. Mostly I don't want to glue and commit to SD, but I don't like the idea of 2 sets of pins in a fairly long rocket. Please feel free to tell me if I'm doing something stupid and there's a much easier way. The allthread adds 50g or so, probably 50g again for the nuts and the eyebolt. That's less than 10% of the motor-less weight and OpenRocket doesn't say it's an issue for stability (well, it's a bit overstable anyway, so it'll be REALLY stable and may weathercock a bit)
*(I wrote 10/32 some places in the pic and didn't go back to fix it. I'm talking 10-32 screw size, not 10/32")
**(which is not going to house anything right now - this is "for future use" if I want to do DD. Also allthread seemed like a slick way to secure the two transitions - way less wobbly than pins)
. Cost for me here was about $8 ozzie dollars each.
