Recovery system anchor for minimum diameter 2.6" diameter aiirframe
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Should be easy enough to make out of plywood.
Neutronium95
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What motor are you planning on using? I'm not aware of anything currently available that would fit into 2.6" airframe without a motor mount.
It's a 2.6" airframe with a 54mm MMT. I could use a 54mm threaded plugged forward closure or 38mm threaded plugged with a motor adapter.
If I could find something like the posted picture for 2.6" airframes, I could use a standard forward closure and any motor diameter(with adapter), as well as DMS motors.
Neutronium95
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In that case you can just attach a kevlar y-harness to the motor mount, Wildman style. That will allow you to use motor eject and won't restrict the length of motor you can use.
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I built a 2.6" rocket with a 54mm mount using Giant Leap's "Hard Point" anchor.
https://giantleaprocketry.com/collections/fins-1/products/shockcord-hardpoint-38mm
It only comes in 54mm diameter. I simply "padded out" a small segment of 54mm motor mount tube and. 2.6" coupler tube with some left over cardboard tubes by cutting out sections to fit. The padded out tube assembly was epoxied into the airframe. I also could have epoxied the hard point in as well but opted to drill holes for countersunk set screws.
https://giantleaprocketry.com/collections/fins-1/products/shockcord-hardpoint-38mm
It only comes in 54mm diameter. I simply "padded out" a small segment of 54mm motor mount tube and. 2.6" coupler tube with some left over cardboard tubes by cutting out sections to fit. The padded out tube assembly was epoxied into the airframe. I also could have epoxied the hard point in as well but opted to drill holes for countersunk set screws.
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I have also 3D printed anchors with polycarbonate with carbon fiber. I use a special design that allows a kevlar cord to be inserted. I anchor it with grub screws.
Make it out of baltic birch or even balsa ply.... min 3-ply base material, and stack crossing until you create the thickness you need, glue up and use an "appropriate" amount of weight. Enough to compress completely but just short of glue starvation (not likely), or deformation (more likely, esp balsa sans AL. Jig up and try cut until you get the size set and then just run a bunch of 'em off. Lighter than aluminim or most composites. And lots of glue surface.... should be able to bond it to literally anything.
Incorporate a thin metal washer in the center and/or on both sides if you think you need to. Shouldn't need it.... (gotta do the math and verify with test... you could need it with stacked balsa... glue bond a THIN alminum skin on both sides of the plug, then trim back with a flush bit and a bearing.) I would start with a solid plug cylinder with just the center hole.... TEST it. Then, if you want, you can get fancy with weight reduction, surface hardening, etc.
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I have used a longer MMT and put an aluminum retainer at the end. I over killed it and used 3 counter sunk screws also.
Same here, extending the MMT to the longest motor size and adding coupler at that point. Only screws for removability.
On my Mach 2 build I just used a fiberglass bulkhead with a 1/2" wide coupler segment epoxied in above and below.
