Kelly
Usually remembers to get the pointy end up
I need a nosecone AV Bay in a 2.6" rocket. I've done this using John Coker's technique, but in a 2.6" rocket there isn't much of a hole left for the sled once you glue in a partial bulkhead to hold the nuts. I thought a threaded connection might give me more room, but I was concerned about strength. For testing, I printed a PETG ring with female threads, epoxied it into a 2" PVC pipe, and also printed a bulkhead (which could hold a sled) with male threads:
I screwed them together, and was able to hang ~300 pounds of weight on the bulkhead, without any sign of damage. Plenty strong for my use, and I only lose a few mm off the diameter. The threads have a pitch of 2mm, and there is about 10mm worth of threads here.
Something like a twist-lok might have made rotational alignment easier (for example, for ensuring that a hole in the NC shoulder will align with an internal disarming switch) but I think the threads are stronger.
Any reason not to thread an AV sled into the NC like this? My plan is to print the female ring, glue it into a 2.6"-ish fiberglass coupler that serves as the NC shoulder, and then print a sled with the male threads and bulkhead.
I screwed them together, and was able to hang ~300 pounds of weight on the bulkhead, without any sign of damage. Plenty strong for my use, and I only lose a few mm off the diameter. The threads have a pitch of 2mm, and there is about 10mm worth of threads here.
Something like a twist-lok might have made rotational alignment easier (for example, for ensuring that a hole in the NC shoulder will align with an internal disarming switch) but I think the threads are stronger.
Any reason not to thread an AV sled into the NC like this? My plan is to print the female ring, glue it into a 2.6"-ish fiberglass coupler that serves as the NC shoulder, and then print a sled with the male threads and bulkhead.