what is the best motor retainer for a minimum diameter rocket?

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mad4hws

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I need to use the ejection charge from the rocket motor, so the internal motor mounts are not an option. Any opinions about Slimlines? I've only ever used the Aeropack retainers, which are great, but not necessarily minimum diameter.

Thanks!
 
Check out aeropacks website and look under minimum diameter they have some that may work. They all require a threaded forward closure.
 
What size minimum ? Anything [most anything]larger than a very small 29mm will not reach maximum altitude with motor delay. Just not long enough.
Altimeter is needed for apogee charge to reach it's highest altitude.

Use sim program to determine time to apogee.
 
Slimlines are great. I would recommend it.

You hit the nail on the head. This is for a 29mm rocket that is being used in the TARC competition. The kids have been using a friction fit, along with a bunch of electrical tape. This past Saturday, the motor ejected out of the tube when the ejection charge fired. So, I either need to do a better job of inspecting the rocket before launch, or we need to come up with a more fullproof way of securing the motor. Thanks everyone for the input.
 
Sticking with the theme of MD you would naturally want to go internal, for the purist mind anything external is a compromise.

Having said that I am not a purist and have two MD with the GLR slimline retainers and love them. But I also have two MD with the aeropack retainers, one 38mm, and one 54mm. The issue with these retainers is the inflexibility of where they are mounted vs the motor hardware. In my 54mm MD CF Tomach I am using the internal aeropack matched with Loki 54/2800 hardware and just drilling countersunk holes to mount the aeropack. This way I can remove it for maintenance. If I need to drill more holes then so be it I can always use a filler ring screwed into any holes above the hardware if using shorter hardware. I originally bought all of the extensions and have the cases and even motor blanks in the case of CTI. The idea was to use combinations of extensions to mount different hardware. But I abandoned this idea after I mocked it up and felt there was too much of a trade off with the extra dead weight and issues with using combinations of extensions.
 
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