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Shock cord on Estes Summit broke...how to fix??

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SirNomad

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So the rubber band shock cord for my little Estes Summit that my son and I like to shoot mini engines broke. Unfortunately the loop in the transition piece where they attached it is recessed in a bizarre manner and I don't have a way to attach the stupid shock cord when I replace it. Any suggestions?
 

samb

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Yeah the instructions don't have alot of detail about how the shock cord is attached. Do you have a picture ?

estes summit.jpg


Can you get a small Estes teabag up into the tube ahead of the transition ?

Did you friction fit the nose cone per the instructions? You could make the attachment there with an extra long replacement cord.




I've done the incredibly old school hole in the body tube as a field repair. Not very elegant but it worked; good enough for Stine and Carlisle ?!?

dirtybird shock cord.jpg




This search may give you some other ideas. Hope that helps.


model_rocket_shock_cord_mount_Google_Search.jpg
 

K'Tesh

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Here's how the Mars Snooper K-20 used to have the shock cord mounted. Might not be pretty, but it'd likely work for you...

Old School Shock Cord.png
 

hcmbanjo

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Here's some ideas from my building blog:

https://modelrocketbuilding.blogspot.com/2012/04/old-centuri-shock-cord-mount.html
https://modelrocketbuilding.blogspot.com/2011/03/starlight-jayhawk-build-part-11-shock.html
https://modelrocketbuilding.blogspot.com/2010/10/estes-shock-cord-mounts-tip.html

The Estes Tri-Fold works well but is sometimes too thick and could block an ejection in a BT-20 body tube.
I would try to keep it as flat as possible. The above posts show some variants.
I'd go to WalMart or a fabric store and buy some 1/8" elastic. Make it twice as long as what was supplied in the kit.

Good luck with the repair!
 

swatkat

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You could tie a knot at the end of the remaining shock cord, then tape it to the wall with a thin strip of highly adhesive tape. the knot should keep it from pulling through the tape and it won't intrude a lot on the small BT. Just make sure to allow enough room for the transition "nose cone" on that rocket to fit through. I've got two of these kits, and they've been really sturdy to date!.
 

SirNomad

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Yeah it was the end that attaches to the plastic transition piece... I'm not sure how some of these Solutions will work with the kind of odd plastic that they used for that piece. It does not seem like a type of plastic that would hold well.
 

samb

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So whadaya think Sir ? Can we fix it ? Do we have the technology ? Or do you have to go with Jumpjet's favorite technique: buy another ? :wink:
 

timb

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In this situation, in BT50 and smaller tubes, I think the best solution is the Holverson Design method: a loop of string (preferably aramid-fiber) in a pool of epoxy as far down as you can reach. Properly done, the result is small and is smooth so it doesn’t restrict or grab at the recovery parts as they exit.
 

LithosphereRocketry

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How tightly is the upper tube attached? I attach my LPR plastic parts with Duco cement, which pops off fairly easily... Then you could just tie it on & reglue.
 

SirNomad

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I tried to pop the transition peeps off of the upper bt5 tube but had no luck. I don't have any replacement bt5 tube or else I would consider just replacing the whole tube there in order to get a secured Loop in there
 

LithosphereRocketry

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How about this...
Drill a hole through the base of the transition, just above the lower lip. Tie a loop in the shock cord, dangle cord into nose, stick dowel through. Glue dowel in place.

I might end up doing this as I have a Zinger with the same problem.

Sent from my LGL34C using Rocketry Forum mobile app
 
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