I am after a thread locker that is the closest thing to been permanent.
The reason I want it is to lock a push bike cassette onto the back wheel but I am using it to mount a disc brake on my gravity racer spun a few off now using loctite 270. So need to withstand high torques trying to undo it when the brakes are applied.
Any suggestion jb weld etc.
Matty

Forget the "JB" bit just "weld" ...........

Problem is welding Chinese steel to Chinese Ali.

Old style screw on cassette..? So the disc screws on? If it has to screw on then you realy need a fixed wheel hub that has a thread for the sprocket to screw on and then a slightly smaller left hand thread for a lock ring. If you can't use one of those then the old poor mans fixed trick to fit a fixed sprocket to a freewheel hub. Then to stop it unscrewing when back pedalling, use a bottom bracket (pre cassette bearings) lock ring on top of the fixed sprocket.

Loctite has special grades for fine threads, the normal grades tend not to penetrate fine threads.

Just clean it up completely and epoxy the whole thing inside the threads. Most of the really strong threadlocks are epoxies or cyanoacrylates.

Correct I have used a cassette to make a hub adapter to mount a disc. All is good on one side as it tightens it but other side unscrews.
Any recommendations on which epoxy or locktite to use.
Matty

So twin discs on a double sided (threaded for sprocket both sides) hub? I'm amazed that a double sided hub doesn't have a (second, l/hand) lock ring thread on one side for fixed wheel. Never seen one that didn't.

More years ago than I care to remember we were experimenting with "offsetting" the cylinder head on our racing TR4 engine. Our head specialist, Peter Burgess, had had good results on his flowbench. We duly machined the stud holes in the block out to a larger diameter and glued in cast iron plugs using Loctite 648. The plugs were then drilled and tapped offset by 2mm. Might have been 3mm. The new hole cut through the side of the plugs leaving behind crescent moon shaped remnants of the plugs. I said it wouldn't work. But it did!
So I can thoroughly recommend LOCTITE 648.