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Is my rocket stable enough?

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Missileman

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I don't know how this happened as I took pains to prevent it.
My motor mount is slightly canted!!
Facts:
MM is 33" long
MM is 54mm dia.
MM is 1/8" off center at the forward end
rocket is 4" dia.
rocket is 90" long
rocket is nearly 4 calipers stable
rocket will fly on hypertek motor
I don't know exactly how far canted the mount is (maybe one of you guys that are a bit more friendly with Pythagoris can figure that out)
Given the slight cant and the overstable rocket how/will this effect flight?
Update: I just measured it and it is actually only 1/16" off center at the forward end.:D
 

xenon

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It sounds like it is stable enough. As an extra precaution though, I think you would want to add a spin tab to one or more of the fins. That way, rather than arcing into the ground, it will just make a nice corkscrew like smoke trail
 

sandman

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A slight spin will even out any off center thrustline and turn the flight path into a helix (spiral).

it should work fine.

sandman
 

powderburner

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Originally posted by missileman

MM is 33" long
MM is 1/8" off center at the forward end
rocket is 90" long
Update: I just measured it and it is actually only 1/16" off center at the forward end.
Mind you, these comments are purely intuition and not analysis, but that small misalignment on a motor mount that long sounds to me like you have no problem at all. You probably have a statistically significant chance of having a greater misalignment of thrust due to imperfections in the nozzle geometry. Obviously, you would prefer to get everything straight. From a practical standpoint, it is probably just fine.

I would feel safe flying it, and without any spin tabs.
 

Stymye

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should fly, but I like the spin tab idea ..... otherwise it could possibly arc out of the range too far
 

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