I fixed the threads on this caliper mount
This is off a customer bicycle. A Jetson from Costco, I noticed it was stripped while adjusting the rear brake.
I replaced entirely in the moment but used the discarded part to learn how to do it better next time.
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Out of curiosity, how did you repair the stripped threads? I gather that this is an aluminum component? Given that this is what mounts a disc brake caliper, would this repair be reasonably safe to ever reenter service?
Looks like heli-coil repair.
https://www.stanleyengineeredfastening.com/brands/optia/heli-coil
Exactly this.
Threaded inserts are an option with more space but bicycle parts are small
As far safety the threads in the part are now stronger than they were originally so it would be reasonably safe to put it back into service.
I guess as long as the threads can take the required bolt torque there's no reason why it shouldn't work.
But I'm always a bit sceptical around brakes, because they're brakes.
I should check all the brake bolts on my bicycle soon...
Probably a wise thing to do anyway. :)
The part is Aluminum and the screw going into it is steel.
The threads wore down due to the part being loose
Steel is harder than aluminum so the screw destroyed the part rattling around in the threads and being pulled when brakes were applied
The heli-coil is steel and secured with red locktite. So now it's a steel on steel interface and is stronger than before.
Torque wise brake mounts typically require 70-90 inch pounds (7.5 ft pounds on the high end) of torque. (In most cases tight is correct)
I repair threads in aluminum electric motors regularly with these and they work wonderfully ! Cheap easy and stronger than the original.
As mentioned, helicoil is one approach, nutserts are another.
All depends on the material and how the mounting works.
Helicoils in aluminum are dead simple and a pretty permanent fix.
Cheap, easy and tough. I use them regularly at work.
100% not dull!
Loved doing repairs like this when I was a bike wrench - incredibly satisfying to save components from the scrap bin.