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Well this started a joke facebook post, turned into a thought experiment, and then finally an actual build.
Could you stuff a 54mm motor into an Estes Pro Series 2.5" kit and have it survive, with no composites?
It seemed silly until I made a sim, and the forces aren't that unreasonable. We wanted to use a DMS motor incase we never got this back and settled on the K535 from Aerotech.
28.5Gs and assuming a 5oz nose cone is only 9ish lbs of force. Do I think I could stack a 10lb weight on a 2" section of unreinforced cardboard tube... sure.
So I set off looking for a Pro Series 2.5" Kit I liked and ended up actually buying one from Bad Boy Rocketry on Ebay. It shipped with two lengths of 2.5" tube, a coupler, 29mm motor mount, and wonderfully cut 1/8" fins and centering rings.
I wanted to go traditional dual deploy since this sims to like 8k. LOC 54mm Motor Mount Tube (MMT) was a little small but sleaving that with some mailing tube brought it up to the perfect diameter. I epoxied them together and had to add a little sliver for the right circumference. Used Electrical tape to keep it all tight during the cure.
Shot a coat of primer and started filling spirals.
The motor mount used the same 54mm LOC tube and more mailing tube as centering rings. I also epoxied on some Kevlar for a recovery harness. Note I left the centering rings gaped to pass over tnuts for the rail buttons.
Got the AV Bay put together and vent holes and static ports all drilled in.
Could you stuff a 54mm motor into an Estes Pro Series 2.5" kit and have it survive, with no composites?
It seemed silly until I made a sim, and the forces aren't that unreasonable. We wanted to use a DMS motor incase we never got this back and settled on the K535 from Aerotech.
28.5Gs and assuming a 5oz nose cone is only 9ish lbs of force. Do I think I could stack a 10lb weight on a 2" section of unreinforced cardboard tube... sure.
So I set off looking for a Pro Series 2.5" Kit I liked and ended up actually buying one from Bad Boy Rocketry on Ebay. It shipped with two lengths of 2.5" tube, a coupler, 29mm motor mount, and wonderfully cut 1/8" fins and centering rings.
I wanted to go traditional dual deploy since this sims to like 8k. LOC 54mm Motor Mount Tube (MMT) was a little small but sleaving that with some mailing tube brought it up to the perfect diameter. I epoxied them together and had to add a little sliver for the right circumference. Used Electrical tape to keep it all tight during the cure.
Shot a coat of primer and started filling spirals.
The motor mount used the same 54mm LOC tube and more mailing tube as centering rings. I also epoxied on some Kevlar for a recovery harness. Note I left the centering rings gaped to pass over tnuts for the rail buttons.
Got the AV Bay put together and vent holes and static ports all drilled in.