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Shock Cord Mount Repair Solution
I think the "original" shock cord has dried and aged while in storage. If it were part of a pair of undershorts, I doubt that you'd wear it, for fear that it wouldn't hold against your waist any longer.

As for the enamel paint, it as a curious yellow tint to it, also like it has turned from age or storage. It didn't occur to me that it might be yellowing floor polish until this moment, but even so, I think it's a quality of the paint.
Lariat Loop shock cord

I use a lariat loop for almost all of my LPR shock cords, with or without a motor hook. Works with any airframe diameter and any motor up to 29mm. (I haven’t built anything bigger.) Streamer, parachute or nose-blow. It's real easy.

For minimum diameter: Use a length of 100# braided Kevlar at least twice the length of the rocket and tie a lariat loop or a slip knot in one end. Tie the other end to the elastic shock cord. I like to tie a loop about a third of the way down the elastic shock cord for the ‘chute and attach the NC at the end. This seems to reduce parachute tangles.

When you prep the rocket, drop the loop down the rocket airframe and out the aft end. To make it easier to get the loop through the tube I made two hooks out of coat hanger wire. One ~ten inches and the other ~20 inches. (My range box is 20 inches wide.) A small hook on one end that will easily fit through a 13mm tube, and a loop on the other end for a handle.
Now slip the motor through the loop and into the rocket. Pull gently on the front of the shock cord to remove any slack. The motor holds the shock cord in and the shock cord holds the motor in. If you want extra insurance, put a wrap of tape around the motor and shock cord.

Yes this puts the Kevlar right next to the ejection flame, but with this setup you can inspect the entire shock cord before every flight and replace as needed. My pre-flight checklist has a box for ‘inspect shock cord’.

For non-minimum diameter: Drill a 1/8 inch hole throught all centering rings at the outer edge, or with an Estes centering sleeve cut a slot on one side. Thread the Kevlar through the holes/slot.

A while back I had a minimum diameter rocket parachute down with the motor out of the rocket but still held by the Kevlar loop!

Hope this helps.
Clear skies and straight smoke,
NAR 31689

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