Removeable fins on BIG rockets

[Handeman]

When designing a removable fin system, keep in mind the leverage of the fin vs the mounting. If the fins are 14" semi-span, and the mounting is 1" for instance, there are going to be problems.

Gerald

Why? Those problems should be able to be mitigated. Wouldn't it depend on how the fins are mounted? I understand there is a large leverage difference, but you get that with filleted fins too.

I'm thinking having both sides of the fin tabs held in place in the way @Alan Whitmore described would supply about the same support as a threw the wall fins with fillets as long as the side supports are strong and well mounted.

 

[Handeman]

That is an interesting way of doing it, but threading those rods in and out could be a real pain. Also there is no side to side support for the fin tabs so if they hit sideways when landing, it seems like they could easily cant sideways in the mount.

 

[bobby_hamill]

That is an interesting way of doing it, but threading those rods in and out could be a real pain. Also there is no side to side support for the fin tabs so if they hit sideways when landing, it seems like they could easily cant sideways in the mount.

The bottom of the fin tab is curved to fit the motor mount tube and the all-thread are 2 for each fin one on top of the other

 

[Voyhager3]

I did bolt-on fins with 3D printed brackets. Not BIG rockets though, just big. See this thread:

Thread 'Bolt-On Fins'
https://www.rocketryforum.com/threads/bolt-on-fins.178405/

I believe that might have been what triggered me to go look into this! That and your cert attempt are very cool stuff.