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Old 03-12-2018, 09:27 PM
olDave olDave is offline
Craftsman
 
Join Date: Sep 2015
Posts: 174
Default Not quite

Quote:
Originally Posted by luke strawwalker
I personally wouldn't rely on one aft fillet on the aft centering ring to lock the motor mount in place... under thrust this fillet will be in TENSION and prone to tearing away, which would allow the motor mount to shove itself up inside ........


You meant shear, not tension....right?

At any rate, I promise you that gluing one CR is more than sufficient to handle the thrust loads of low-power motors. If you would like to convince yourself, spend a few minutes and a few scraps from the build box and make a MMT, then install it inside some BT. Then add a dowel or length of cord glued to the inside of the MMT, and let everything dry thoroughly. Then, grab the BT in one hand and the dowel in the other hand and pull. It's gonna take a whole lot more than just a few pounds to tear apart, and the BT will be destroyed in the process....this goes way beyond the thrust loading levels of low-power motors.

But by all means, if you are a "belt-and-suspenders" kind of guy, glue the front CR also. It's easy to take your bamboo skewer and stick it through the front end of the BT to smear a little glue around the front CR, from the front side of that CR.
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