Apprentice S Stripped theads on prop connector

[Khrhunter]

New to all this fun but Im slowly but expensively getting it..... My main issue now is the set screw keeps striping in the aluminum prop connector. Its almost like the set screw it too short butn I went thru 3 today.. Is it something Im doing?

 

[quorneng]

A set screw I [resume it uses an Allen key. Both of these are made of hardened steel. The prop adaptor is much softer aluminium. Too much force will always strip the ally thread first. I am afraid you prop adaptor is scrap unless you can rethread it to fit a bigger diameter set screw..
The best solution with a new adaptor is to file or grind a small flat on the motor shaft. This greatly reduce the force the set screw has to apply to grip the shaft securely.
There are collet prop adaptors that use the force of the prop nut to squeeze the prop adaptor down to grip the motor shaft. They do have to be exactly the right size for the motor shaft. They are very effective. The common problem is trying to get them off!

 

[Khrhunter]

this motor has the flat spot on the shaft already maybe im just not getting tight enough afraid its gonna strip threads but next thing you know it comes off. the set screws are about 1/8 inch at tops just seems like a flaw and has to be better

 

[Piotrsko]

All the set screw has to do is provide SOME force to prevent the prop nut from comming loose. Doesn't need more than a pound foot or two. If it's against a flat, finger tight is enough. If you want, longer set screws are available for purchase locally to you, but unless you're in the EU, metric is tough. There's also a thing called locktite or thread locker which comes in various strengths from mild to destroy nut to take it off. You could even use elmers, titebond or hot glue. The other issue with longer set screws is that they will unbalance the motor which causes much bigger problems with the controls and motor

 

[tetraodontoxin]

Make sure your set screws and taped holes are the same thread. Some thread sizes are close enough to seam correct, but will thread into each other with varying levels of play. if you can thread the set screw into the taped hole but there is still a bit of play, I would check the size of the screw and taped hole. I would also make sure you did pull the threads out of the taped hole as well. aluminum is great, but the thread strength isnt always the best, especially on small diameter fasteners. a few years ago, I would direct you to a local Fastenal, but I think the majority of the locations require an account and dont have an open store front. But I know you can source a lot of this stuff from online venders. When you are tightening the set screws, do you feel the screw tightening?