DynaSoar
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I'm doing a 29mm minimum diameter bird and building it for max engine size. I'm estimating well over Mach. Being minimum diameter, I can't very well slot the tube. How else can I insure the fins won't pull loose? I though of gluing a thin slat to the bottom to give it more surface contact with the tube, but realized that only the slat would have more contact; the fin would still have the same contact area. Nor can I drill holes in the body for the epoxy to seep through and "rivet".
The tube is heavy paper (T52-H from BMS, a bit lighter than AT's motor tubes) and I'm planning on plywood fins. I could go with G10 fins, but don't see much benefit from that.
Drill a few small holes near the root and thread some thin material through them, which will then be embedded in the fillet material?
Drill the holes near the root and let the epoxy seep though those?
Glue a thin strip just above the root, which will be embedded in the fillet?
If fins tend to tear off due to sheer, maybe just the foreward portion needs the extra beefing up? Too bad there's no 29mm Acme fin can.
The root of the fin will not be completely flat. There's a motor retainer over the aft portion that the fins will have to have notches cut/sanded to fit. But this shouldn't change the problem or solution much.
Would CyA on the root with epoxy fillets be better than just epoxy?
The tube is heavy paper (T52-H from BMS, a bit lighter than AT's motor tubes) and I'm planning on plywood fins. I could go with G10 fins, but don't see much benefit from that.
Drill a few small holes near the root and thread some thin material through them, which will then be embedded in the fillet material?
Drill the holes near the root and let the epoxy seep though those?
Glue a thin strip just above the root, which will be embedded in the fillet?
If fins tend to tear off due to sheer, maybe just the foreward portion needs the extra beefing up? Too bad there's no 29mm Acme fin can.
The root of the fin will not be completely flat. There's a motor retainer over the aft portion that the fins will have to have notches cut/sanded to fit. But this shouldn't change the problem or solution much.
Would CyA on the root with epoxy fillets be better than just epoxy?