Weak Spot in a Body Tube-Repair

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Woody's Workshop

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Hey guys,

Working on a rocket kit, it seams to have a defective/weak spot in the wrapping of the main body tube. It had a spiral buldge when I took it out of the package. Mabe it got stressed in shipping or handling. Already have the engine mount in. I'm thinking I'll just add a few tube couplers to reinforce it before I go any further with the build.
It's a 2 stage rocket from Estes, the Hyper-Bat.
It's one my bud sent me, so it didn't cost anything, and maybe why it didn't make it through Quality Control.

Would any of you use this method to reinforce the tube?
Or would doing the math and ordering a longer tube from Semroc and put a full liner in it be better? My only concern would be stability.
Since the fins are such a wierd shape, it would be hard to draw the fins in RockSim so I'm hoping the couplers will work.
I am not concerned with loosing altitude at all, I'll probably only use A's & B's to launch it so I can get it back
Thanks
 
Depending how accessible the spot is, I would probably soak the area all around the tube at that spot with thin CA. Let it sit overnight, call her done. Tube coupler with wood glue or some such will also work but depending how far in it is, might be tough to do without getting the coupler glue-locked before it gets to position.

I understand this is on the main body tube, and you've already got the motor mount in, so access is from the forward end, I guess. How far aft from the forward opening is the problem area?

If it's hard to access, you could always make a pinhole and dribble in the thin CA through it, then rotate the tube to spread it around. Or sand the glassine off the area and let the CA soak through.

Or you could just ignore it and probably it would work fine too. I've found primer and paint can be close to a structural element in these birds!

Marc
 
The weak spot is about 1" above the top of the engine mount.
Body tube has been sanded and has had a double thinned coat of TiteBond II applied and sanded already.
Sliding a few couplers down that far is not a problem if you know the tricks.
First, take a small brush and wet the inside of the body tube, mark the depth on the handle of your glue brush and apply a good thick coat of TiteBond II in the proper location inside the body tube. Next get the coupler(s) wet with water and use a dowel to slide the couplers down. The water is like a lubricant until you get the component where you want it. Especially when you can't coat both mating surffaces. It's a bad spot, I thought glue would solve it but after a lite sanding it's obvious that it is not. The tube will not stay straight and true, so it will have a small kink in it, obviously effecting flight path as it is not a straight and true body tube.
I do not like CA glue at all. I will use epoxy, but I very, very, and I mean very rarely will use CA glue. It has it's place and I have not had luck with it on rockets to save the last few hairs left on my head. Sorry, but that's just me.
 
Just to make it flyable CA and a spiral wrapping of masking tape. If pretty is a concern (probably is), see everyone else's comments.
 
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