Attaching derailleur - Damaged hanger
 

Hi guys, wondering if somebody could advise with my trouble, its not that big deal but anyway,

I have ripped off my derailleur hanger and lost threads in frame and now cannot attach the hanger to the frame

I havrapped new threads into the frame - but bit larger as it was about 0,5cm and now its 0.8

im trying to attach derailleur/hanger but im not sure how should be done.

Shall i drill new thread into my hanger? Or is there any reduction i could insert into the frame?

Ive heard that if you drill the derailleur hanger it becomes fragile,

My frame is alu and hanger aome other hard material so cannot do it with tap and die set and need drill probably

Many thanks guys.

Pete

Why not just try a band on hanger?

not sure how, its rear mech i forgot to mention. Can donit with rear mech aswel ?

There is this option that replaces the nut on the quick-release skewer: https://problemsolversbike.com/produ...versal_-_21655

Can you helicoil it?

Hard to tell from your description, but if the hole your derailleur mounting screw threads into is stripped, it can be repaired with one of these: https://wheelsmfg.com/ds-1.html
If you have a removable hanger whose mounting holes are stripped you can repair the holes with a Helicoil, tap it out to a larger size,and use a a bigger screw or use a jam nut behind the dropout and a short screw to mount it if there is room.
If you upload some photos to a photo-sharing site and post a link we might be able to help you better.

D'oh! I was thinking front. Not rear.

My only comment might not even apply, the OP's description is so lacking I'm not really sure what is going on. BUT, a 3mm increase of fastener diameter (from .5cm to .8cm) is a HUGE increase in both diameter and, I assume, thread pitch. Generally when one tries a larger fastener in a stripped out mount it's typical to go up only one size of bolt/fastener. Not 3 sizes. Andy (Who's wondering what really is going on. Another reason to post photos or a link to a photo sharing site.)

I surmise the OP has a claw type RDER and stripped out the attaching screw, which is likely 5mm.
And then drilled the hole way too much oversize? Should have started at 6mm?

Not sure if "claw" will handle having the hole enlarged to 8mm?