Engine Retention

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tjkopena

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@kuririn, I saw your comments on MMX engine retention in the current wishlist thread over in the General Discussion forum. Do you have a lot of MMX motors pop out? My little MMX fan group has lost extremely few motors. I can only definitively recall two out of dozens of flights the past few months, and one was a downsize of an old glider design for which that was intended behavior. I was really surprised that we don't see more motors ejected but theorized that the ejection charge just isn't strong enough if there's any other way for the pressure to escape. If you see it fairly often, I'm curious if that's a product of slight differences in tube tolerances across manufacturers.
 

blackjack2564

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I always leave 1/4in of motor tube stick out, thneen wrap tape around motor and tube.
NEVER have had lost motor.

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kuririn

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Since friction fit or tape wrap is the only method available that's what I've used.
The problem for me isn't motors popping out but the tediousness of cutting little strips of scotch tape to get just the right fit. Too much and it won't go in. And scotch tape works better in my experience than masking tape (too thick). Not to mention removal. So I was looking for an easier way, like a wire hook.
Will be doing some experiments and fabrication.
 
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