Harness Replacement Ideas

Antares JS

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Hi everybody, I've got a problem and would like to tap the hive mind for a solution.

I had a motor cato today (my own fault, should have used a plugged forward closure when I knew the delay element was damaged) that resulted in some propellant flame escaping through the forward end of the motor and up the rocket's booster section, and while the airframe of the rocket is pretty charred internally, I should be able to put it back into service with a little work. The problem is that the nylon harness I had that was permanently installed on the motor mount under the forward centering ring is now a melted, useless mess that I easily removed from the rocket by pulling on it. I'm now in need of a good way to permanently install a new (kevlar) harness into a high-power rocket booster section when the motor mount is already installed.

FYI, the rocket is a PML X-Calibur kit, which is a 2" rocket with a 38mm motor mount, so not much centering ring to work with. I converted it to dual-deploy, so the booster section only needs to hold the harness itself and a streamer.
 

jmasterj

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You could get a hardpoint from Giant Leap:

Or you could just install a bulkhead with an eyebolt in it, perhaps with a piece of coupler above it for some additional glue surface area and confidence in its staying power.
 

DragonRocketry

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I did one that was 54mm tube to 38mm motor mount (forgot to put an anchor in when building). I drill up through both centering rings and the fished a piece of 1/4" flat kevlar out the bottom. I then knotted it and epoxied it to the bottom CR, but my bottom CR was not flush with the bottom of the rocket as it sat 1/4" up inside the body tube.
 

tsmith1315

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You could cut a hatch in the airframe behind the fwd CR and use it to fish a line around the MMT.
 

cavecentral

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Try putting the new harness around a bit of coupler, then installing the coupler as deep as you can. Cut out a sliver if needed to get passed rail buttons, etc. that might be inside the tube wall. Of course, install it deep enough to allow the nose cone of av bay to fit properly.
 

rocketace

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Convert it to a zipper less design? Cut the BT short and add a coupler with a bulkhead to attach the new harness.
 

Antares JS

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With the slimline retainer I don't have much access to the centering rings, and I would prefer not to cut the tube and mess up the long name decal (it's in a cursive font so it's one piece).

I think @jmasterj's solution is looking the best for me right now.

20221009_112222.jpg
 
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