Rounded off mech hanger bolt in a titanium frame - suggestions?

Fireball XL5

The mech hanger on my titanium frame is bent but when I went to remove it I rounded off one of the counter sunk bolts that attaches the hanger to the frame. I say bolt but it is more akin to a grub screw. I am not so keen to cut a slot in the head of the bolt as the countersunk element will also result in a cut to the titanium frame. I have tried to drill out the bolt but every drill bit I have used has simply become blunted and made no impact.

Help !

Any thoughts?

Homer1798

Try drilling the grub screw out from the other side as the drill bit will be travelling the same way as the tread in the frame and with a bit if force may actually unscrew it fro you.

StevieGriff

Homer1798 wrote: »

Try drilling the grub screw out from the other side as the drill bit will be travelling the same way as the tread in the frame and with a bit if force may actually unscrew it fro you.

This ^. And I know it seems obvious but make sure you aren't using a masonry or wood bit, seems a bit odd that you were blunting the bits.

triggermortis

You really need an easy-out to remove this screw. You drill a hole where the existing allen key would fit in and then use the easy-out to screw out the damaged screw. If you're not confident doing it yourself then maybe a bike shop or garage can help

Cee-Jay-Cee

Are you sure your using proper metal/steel bits? They shouldn't be rounding off unless the screw is made from Some sort of ultra toughened steel/carbide.

macnab

The bolt might be made from stainless steel, if so you will need to use a slower speed drill and a lot of force (low speed, high feed)
Stainless bolts are usually not magnetic, so try that first to see if your bolt is stainless.

myclist

Try this. If its an allen screw get a Torx key thats one size bigger and press it in with a vice grips or a g clamp and you should have no problem removing it. You could try driving the Torx bit in with a hammer if you are careful.