The "U Loop" Shock Cord Attachment Method

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.....OpenRocket's ..... "Chuck Norris"
TRF Supporter
Mar 27, 2013
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Tie/sew a loop on one end of your shock cord, pull it through the eye bolt/U bolt. then attach a quick link to it. Then create another loop that will be (when attached by the quick link on the other end) almost even with the front of the recovery bay. Attach them by the quick link. To prevent possible entanglement of the parachute, a sleeve could be slid down the length of the loop.

To inspect, just pull the loop of shock cord down through the motor tube, or around to see how things look, it it's good, pull it back into the normal position.

When replacement is required, you can tie the new shock cord to the loop at one end, and pull it through the eye bolt/U bolt, make your loops and you're back in business.

Sure, it might use nearly twice as much kevlar, but the ease of use will likely be well worth that.

This could be adapted for other harnesses, where the shock cord is a single length of material, but I think as two parts would be more cost effective in the long run.
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Another possibility is to pass the shock cord through to the back of the rocket, and loop it over the motor tube, then secure it with either screws, or the retainer. I'll call this 'The "Pass-Through" Shock Cord Attachment Method'. In the image below, the blue section is a flame resistant sleeve, the green is a pipe or a straw that you can pull the shock cord through. You can easily pull the shock cord out through the back of the rocket to inspect it. If it needs replacement, you can simply cut off the end of the loop, glue its replacement to the end of the old cord (or a skewer, or something like a piece of piano wire) to fish the new line in.