A little while ago I bought a pair of plywood hearts from the craft section of Dollar Tree or General or whatever. I cut them down their middles so that each one gave me two fins. I wrote about that in the What Did You Do Today Rocketwise thread.
Here's a quick and dirty, very rough design file.
In order to keep things simple, since the plan is to use this for a cert flight, I plan to use motor ejection plus a JL chute release. I want a tube coupler for length, so I figure to build a baffle into it since it's there. I may attach the coupler/baffle with removable rivets so that I can take it out to clean or replace when it gets a lot of ejection gunk inside.
The fins are thin and not of the best quality plywood, so I will definitely be glassing them, a first for me. I'll probably also glass over the fin-tube joint, in the fillets. But I'm thinking I don't need to do the whole tube if I use LOC heavy wall cardboard. I know plenty of flights have been successful on J or K motors with that stuff unglassed. But maybe I'll bite the bullet, swallow my insecurity, and glass it anyway. Or maybe I'll just by some fiberglass tubes. Or Bluetube. Opinions?
Getting the fin shape into RockSim was an interesting process, so I think I'll write a tutorial and post it to the Techniques subforum. It involved hacking the .rkt file in a plane text editor, so not for the faint of heart.
Here's a quick and dirty, very rough design file.
In order to keep things simple, since the plan is to use this for a cert flight, I plan to use motor ejection plus a JL chute release. I want a tube coupler for length, so I figure to build a baffle into it since it's there. I may attach the coupler/baffle with removable rivets so that I can take it out to clean or replace when it gets a lot of ejection gunk inside.
The fins are thin and not of the best quality plywood, so I will definitely be glassing them, a first for me. I'll probably also glass over the fin-tube joint, in the fillets. But I'm thinking I don't need to do the whole tube if I use LOC heavy wall cardboard. I know plenty of flights have been successful on J or K motors with that stuff unglassed. But maybe I'll bite the bullet, swallow my insecurity, and glass it anyway. Or maybe I'll just by some fiberglass tubes. Or Bluetube. Opinions?
Getting the fin shape into RockSim was an interesting process, so I think I'll write a tutorial and post it to the Techniques subforum. It involved hacking the .rkt file in a plane text editor, so not for the faint of heart.