Pretty sure I know what the answer is gonna be .... but is there any way to remake threads on an aluminium bolt?

Managed to damage my rear derailler hollow bolt, new one costs £ 18

Manged to screw into the hanger but next major knock its gonna pop out I am sure.

[Edited on 30/6/09 by 02GF74]
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LOL no I'm afraid you can't make material thats not there. You can certainly run it down to the next size, but then it will be too small for the mech hanger.

Could you perhaps run another bolt through the middle and through the hanger? Kinda like clamp it on. A nice hard steel bolt would easily take the bashing.

That's not a part that normally wears out so ask around on the bike forums to see if anyone has a worn out mech with a good bolt on it.

Duncan

Pick up the cheapest rear mech in the range (I'd guess the X.4 at ~£17) and bastardise it for parts?

Fair chance the bolt will be the same, only steel, so won't die as easily.

Least, that's what I'd do, and if It didn't work, I'd reassemble the one I'd bought and return it.

There are a few decent re-thread sets available, but none of the worthwhile sets are cheaper than £18.

I was kinda hoping this was fixable with technoweld or similar, build up the diameter, turn own and cut thread .... sounds easy but I bet it won't be.

not sure what thread it is but it looks fine, proabluy M10.


all that messing would mean it would be cheaper to get the bolt.

's a prob with top notch components, they wrok great but if you bend 'em, it is gonna cost £££££

You could re-assemble it with Loctite High Strength Retainer on the threads. This is very strong but may be a problem if you subsequently need to diss-assemble, unless you can heat it which breaks the bond.

I'd go with the high strength retainer, then buy a new mech and hanger when it finally gives up (assuming the hanger is replaceable)