Anyone know at what thrust a ttw, 1/8 balsa fin will shred

I.m sure it has a lot to do with fin shape and drag. Just wondering what experiences everyone here has had and if there is a rule of thumb. Thanks!

I gather that problems generally start to manifest around 500mph or so, and ease somewhat around mach 1.1.
Rex

Apogee's Aspire is a Mach 1 capable rocket that uses papered balsa fins (surface mounted) according to their article.

If the win is wall mounted, the glue will probably fail first, so it's more of a function of what kind of glue you use. On the other hand, a hard landing could do a number on your fins, too.

https://www.info-central.org/?article=138

https://www.google.com/url?sa=t&rct...=U4Em-U5rfjsjZetXq-a2mw&bvm=bv.75558745,d.aWw

There is no rule of thumb.

I have a read and studied this problem for quite a bit. And I have learned enough to know that I still have a lot to learn on the topic. But what I can say is that there can be a lot of variances (it is not an isotropic material) between balsa, and what one lot of balsa can do the other may not. That's a design problem that has a lot of uncertainty associated with it regarding unreinforced balsa. If you think you are going to go that fast, go with 1/8" plywood and the risk goes down. A lot (IMHO). At least paper the balsa, or better yet fiberglass it (that's what I do).

Greg

I think greg nailed it. There's just too much variance in balsa to know how it's going to react to high speeds. Best to reinforce it or use a stronger material.

Thrust I'm not sure, but I do know(cause I saw it) an f50 in a 120g rocket can shred. I do believe his fins were not real staight in first place, so I'm sure that helped the shred.

1/8" balsa with the grain going the wrong way, highly swept back,and attached semi-straight will survive a minimum diameter D12-0 to E12 flight.
OR file:View attachment 5XB cluster.ork

Thanks for all the answers and advice!

nute said:

1/8" balsa with the grain going the wrong way, highly swept back,and attached semi-straight will survive a minimum diameter D12-0 to E12 flight.
OR file:View attachment 184677

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AAAANNNNDDD you got it back. That thing hauled! lol