Building Test to Destruction (part 4)

All truly great ideas originate in the shower. So where did the idea of the shower originate?

This morning in the shower I realized a fair amount of my problems with my fin were due to its shape, in particular the 2-segment, concave-angle leading edge. Makes it hard to sand, and impossible to roll paper over that edge.

So if you have a design that’s too complicated to allow it to be executed easily, what do you do? That’s obvious. Make it more complicated.



The original odd fin shape was purely for visual interest. By splitting the fin into two parts I think I’ve doubled down [see what I did there?] on the visual interest; at the same time, instead of one difficult leading edge, I now have two easy ones. They can be rounded first, then papered over. I can leave the other edges square. Problems solved.

Well, that’s a theory, anyway.

A lot of really stupid ideas originate in the shower too, you know.

(OpenRocket says this design has more stability than the previous one, by about 0.2 cal. I’m very skeptical. I’ve played around enough in OR to come to believe it’s not necessarily handling multiple fins correctly. In particular if you butt the two fin sections together, making in effect a single fin, the CP isn’t in the same place as if you put in a single fin the same size and shape. Perhaps it’s assuming end effects that aren’t correct for fins close together.)


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