Reinforcing slotted tube

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Well-Known Member
Jul 14, 2009
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On my current build (Big Daddy), I'd like to try the method of fully slotting the body tube to the rear, assembling the fin can as a separate unit, then sliding it in.

My questions is, what needs to be done about closing up the remaining "exposed" slot behind the fins? In the case of the Big Daddy, the fins will actually cover that area, so any reinforcement may need to be done on the ID of the body tube.

Edit: I do realize this is not needed for a BD build; I just thought it would be a good kit to try it out on. I have already applied 2 layers of 2oz glass to the body tube, as well. This definitely makes the body stiffer, but I'm not sure if the slotted rear will be ok.

Edit of edit: I do realize the fiberglass is not needed for a BD build; I just thought it would be a good kit to try it out on. It's being built with a 38mm mmt, as I imagine it will be far too heavy for the recommended E9.
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No need to reinforce it.

I had a Big Daddy I flew on 38mm motors -- stock Estes tube, with no reinforcement on it.

What I did do was fiberglass the fins, then fiberglass them to the motor mount. The tube itself had the slots extended so it could be slid down over fully assembled motor mount.

Flew it four times: I131, H97, H97, G69. I quit flying it because I lost it.

On the G69. :confused2:

We found it a year later, after mice had made a home in the tube. For a rocket that had sat out in a field over the winter, it was in amazingly good shape, although the nose cone had been run over by a tractor, and was crushed. I was able to salvage the motor case.

So, back to your question... No need to worry about it, especially if you have the tube fiberglassed.