Model Boat Mayhem
Technical, Techniques, Hints, and Tips => Other Technical Questions... => Topic started by: ntg06 on September 10, 2009, 09:11:09 am
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Hi,
This is a bit obvious, but not sure how to stop it!?
I have just connected the motor to the prop shaft via a universal joint. The motor end has a grub screw, and so can be locked to the shaft.
The prop end is an M4 right-hand thread. This is fine in forward, but when I switch to reverse to thread undoes (pretty obvious really!).
How do I stop this happening? Do you use thread lock or something? Or maybe I have bought the wrong coupling?
Also, what stops the prop loosening in reverse?
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You need a lock nut on the shaft to tighten against the coupling to stop this happening.
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Same with the propellor. Position the locknut to give the minimum amount of shaft play within the tube and then firmly screw the prop down onto it.
Colin
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A dab of Threadlok on the threads won't go amiss either.
Barry M
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OK, thanks for the advice.
Do you use any kind of locking washer with the nut, or just the nut itself?
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Washer is not needed
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Barry M, I concurr, Loctite the threads every time and props and shaft coupings loosening will be a thing of the past. I actually don't even use a locknut anymore and I swinging 50mm 5 blade props. You will need heat to soften the Loctite when you eventually wish to dismantle.
Superglue and other like stuff is not a substitute for proper threadlocking fluid so don't be tempted to use these products instead.