Help!! MDRM schock cord mount

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the random rocketer

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Help I did something real stupid.
I tried to copy the shock cord mount smugglervt showed on his MDRM build and did not epoxy the eyebolt in place.
I get to the launch site and start prepping my model and start pulling the shock cord out to add wadding, and it kept coming and coming. The eyebolt had rattled completely out of the nut and washer.
So now how would I recover from this? Glue the Kevlar down? To what? Cut holes in the body tube and retrieve the nut?
mmt.jpg If this posts this is what I was trying to do.
 
If you cut a hole in the BT where the bolt should go, you may be able to retrieve the nut, re-thread it on the bolt, and epoxy it. Nylon lock-nuts help, too. Not sure how you would cover the hole.
 
Threaded insert. I've used them for motor retention as well as recovery point connections when I've hard to. Not as good as a washer and nut, but better than epoxy to the wall (LOC style) Drill your under-sized hole, douse with thin CA and then thread the insert in. When cured, it'll support the recovery point for a MDRM unless you load it up with motors having 5g of BP for an ejection charge.
 
You could drill a hole up through the lower and middle CRs directly below the eye bolt, which would allow you to 1) retrieve the nut, and 2) insert a socket with the nut back in up to the top CR and reattach it to the bolt. This would leave you with a hole that's easier to patch than through a sidewall, or a permanent hole that nobody sees unless they're looking at the bottom. Hope you're able to remedy it one way or another...
 
Drill a hole through all three CRS, they don't need to large enough to retrieve the nut... Drip in some glue to stop the nut from rattling around. Then thread your kevlar through all 3 holes, and tie a loop into the end of it. Secure that around the motor mount and lock it down with a couple of screws with overlapping washers.
 
What about just drilling a hole about an inch or two next to the original hole in the forward CR and just fishing the Kevlar down one and up the other and creating a big loop of Kevlar?
 
What about just drilling a hole about an inch or two next to the original hole in the forward CR and just fishing the Kevlar down one and up the other and creating a big loop of Kevlar?

An alternative, if the motor mount is either 38 mm or 54 mm, is to use the Giant Leap Rocketry "hard point" device which is a light weight machined aluminum product that can be epoxied just above the forward centering ring. The hard point has an eye bolt with nut centered in the device to attach a shock cord to. Good luck!

Fred, L2
member of ICBM
Camden, SC
KG4YGP
 
Long story short. I had a forward closure failure and fire that toasted the body tube in front of the motor mount. In the rebuild I corrected the mistake of not epoxying the shock cord retaining bolt.
 
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