My next project.

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Senior Space Cadet

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After I finish some of the projects I've already started, I'll move on to this rocket. Already have parts on order. I'm debating if I should make it longer. I'll weigh all the components and do a more exact design before I make a final decision.
This uses a 41.6mm tube and I'm planning on using 24mm motors. I could put a 29mm motor in this design, but I'd have to change to sturdier materials. I'm already a little concerned, after reading what people had to say about thin wall white tubing, which is what I've been using. It is pretty flimsy. Haven't had trouble with paint yet.
Screenshot 2020-07-07 10.03.55.png
 

Charles_McG

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Paper tubing is stronger than you think (As long as it's not damp. - Keep It Dry.)
Here's a picture of a compression test I did on Estes BT-55 (33mm) tubing.
ImageUploadedByRocketry Forum1501884017.361770.jpgImageUploadedByRocketry Forum1501884085.137632.jpg

It was for a 1/5 scale Nike Apache. Now, it did happen to fail with a G65 - but it was coning also. (The stage separation charge tended to blow out a fincan side panel between fins in that design.) Bending strength isn't nearly as high - so fly straight. Which is the plan anyway.
 

neil_w

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After I finish some of the projects I've already started, I'll move on to this rocket. Already have parts on order. I'm debating if I should make it longer. I'll weigh all the components and do a more exact design before I make a final decision.
You'll find if you play around a bit that shortening the root on the fins will improve your stability margin by pushing more of the fin area backwards. Also, note that unless you have a motor selected under "Flight configuration" then you are not getting useful information about CG. I suggest configuring it with the largest engine you expect to fly with it and doing your design that way, so you won't be surprised later. If you plan to fly with Estes E12s then that's the one to select.

This uses a 41.6mm tube and I'm planning on using 24mm motors.
FYI: Almost no one refers to it as 41.6mm tube. It's commonly referred to as BT60, the original Estes designation.

I could put a 29mm motor in this design, but I'd have to change to sturdier materials. I'm already a little concerned, after reading what people had to say about thin wall white tubing, which is what I've been using. It is pretty flimsy. Haven't had trouble with paint yet.
Well, if you're talking about BT50 motor mount, then yeah it is flimsy but it works. I prefer BT50H nowadays but thousands of rockets have and continue to fly just fine with BT50 motor mounts. 29mm motor mount tubing is generally quite stout.

The BT60 would be fine even with a 29mm motor in there. You'll likely need to adjust the design, though; what you're showing there won't be stable with the weight of a 29mm motor back there.
 

mbeels

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I'm already a little concerned, after reading what people had to say about thin wall white tubing, which is what I've been using. It is pretty flimsy.
As Charles already mentioned, it is stronger than you may think! I've flow thin wall Estes tubing on F and G motors with no extra reinforcement, and it has done fine. The exception would be if something gets screwy during the flight and it buckles, or if you have a really long rocket like those Super-Roc rockets.
 

Funkworks

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Where will you get the tail cone? I once looked around for small tail cones but didn't find any. I think that one is bigger though.
 

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