Straightening and Beveling G10 fins

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Well-Known Member
Jan 18, 2009
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Hi all,

I've been working on a PML Thunder & Lightning for the past month or so. I have the bottom stage pretty much done, the fins are atteched and filleted and all it needs is a motor retainer and filleting. Now I'm moving to the top stage, and the fins are warped. They may be warped from the factory or just from dropping them, but they do have quite a bit of bend in them. I want this rocket to fly as straight and true as possible. Is there any way to straighten out the fins? Will a layer of 6 oz. glass on both sides fix them, or do they need more than that? Also, I'm aiming for a knife edge bevel on the fins, so if I do put glass of the fins I'll sand through it while I'm beveling. Will the fins stay straight, or will they need another layer of glass?