Motor retention hacks?

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spacepotato88

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Hi!

I was wondering if it's possible to launch a rocket without a forward motor retainer. I bought a 54mm minimum diameter fiberglass kit and mounted my aft retainer alright (p-type), and am just now realizing I need a forward one above my engine and I don't realistically have time to buy one. Is there any way to hack this issue? I was thinking of installing an eye bolt into the side of the tube (or maybe a threaded rod) above the retainer but not sure if theres a better way. If it matters I have an aerotech-54-1280 motor set (complete set from bay area rocketry). Just trying to launch my L1 haha.
 

tsmith1315

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If you have an aft retainer in place, you need a recovery anchor point, not motor retention, is that right?

Where are you in the build process, are you doing dual deployment, which front closure(s) do you have...
 

spacepotato88

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Yeah, sorry I'm new to rockets of this size. It's really for an anchor recovery point yes. I have pretty much everything put together now, this was the last thing (short of packing parachute, motor, etc). I am rigging a dual deployment as a single deployment (so effectively a single deployment, wanted to learn to walk before I ran). As far as forward closures I bought the 1280 54mm set from bay area rocketry it has a cap but I'm not sure what it's called (if you Google it it should come up, but it doesn't list what the cap is called so I'm googling to figure out what it's technical name is, but there's a picture on their website)
 

tfish

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yep..

and use some sort of shock cord protection ...which can be as simple as a couple of layers of duct tape or even the electrical tape too..

Tony
 
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spacepotato88

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Awesome, would Kapton work? (For some reason I have more of that than anything else)
 

Buckeye

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These 3 knots are very secure. I am using the constrictor knot on my 54 min diameter.

 

SpaceX76

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Are you always flying with dual deployment is it redundant?? If you are flying redundant you could put a bulk head with an eye bolt in the center. You would loose the ejection charge and would need vent holes to get rid of the gases.
 

dhbarr

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Were you being serious when you said you are attempting your L1 cert with a 54/1280 casing? Every reload I see for that casing is a “J” impulse, which is an L2 motor…
Case spacers are a thing, but I'd hesitate to recommend them in this scenario.
 

prfesser

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Are you sure that is a 54 mm 1280 casing? I think the 54/1280 casing is significantly shorter; it should be about a four-grain motor, about 12" of propellant. The casing in the image looks more like a 38/1280 casing. Of course I may be full of old bootlaces and sardine juice.... :)
 
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