Astron Sprint XL Tube issue

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Todderbert

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I bought one of the Sprint XLs from the Estes sale page. When it arrived I noticed the entire length of the tube is out of round, more of a slight oval shape. I think the model's bag was too tight and pressed on the tube since the day it was packaged. I contacted Estes and they said they would send a new BT. Has anyone fixed an issue with an oval body tube before? I thought about it and the fin section would be round after the motor mount was fitted in, and the top where the nose cone attaches would be ok, but the center to top mid section still would have this slight oval to it. Would adding a baffle be a good choice here if I was trying to salvage this tube? again its a slight oval across the length of the tube. I think it would fly straight, but not sure how it would look after being painted, would you notice the out of round areas?

I also thought about cutting a section of this oval tube and making a mini payload bay with it, I could use the coupler to help straighten it out. Ideas?
 

Nytrunner

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You could try using a coupler (or make one of your own) to reinforce it.
 

K'Tesh

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If you were to go with the cut it down for parts route, I'd try this, but I can't be sure of the results. Painting the inside of the tube with a water-based wood hardener and then blow up a pencil type 260 balloon (but not at full pressure, you'd want the balloon to still be soft) inserted in it. After the hardener cures it should stay round, presuming it doesn't pop the balloon. You could use the resulting tube for a few zipperless recovery bays and not have to worry about glue adhesion to the resulting tubes.
 
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Rex R

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the trick is the controlled application of heat...I would suggest a hair dryer. 3 or 4 centering rings inserted into the tube w/o glue (a piece of bt55 works nicely for this) to hold the tube in the desired shape, then direct the hot air over the tube until the surface gets hot, allow to cool. the tube should now be round. you may want to practice a bit with a scrap of tube...because if you get it too hot the tube will come apart. note; one can use a dry iron and a mandrel to remove creases but, that takes practice. good luck,
Rex
 

Skp

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I had the same problem with a Vagabond. It was not crimped or creased so I just spent some time rolling it in my hands while watching a movie with a nose cone stuck in each end. It rounded up just fine.
 

Todderbert

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thanks for the info, Estes did come through with a new BT. I'll use the centering rings/hair dryer tip to see if I can straighten the old one.
 
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