Headless Bolt

[Ming the Merciless]

Success - I bought a set of five HSS 3mm bits and used them in succession until I broke through which happened in no time at all. This allowed me to use my screw extractor bit to complete.

An unexpected bonus is that the threads appear undamaged as the new mudguards are now firmly in place.

Thanks to you all for your kind attention and knowledge.

I hope you greased the new bolts to prevent a repeat

 

[si_c]

I hope you greased the new bolts to prevent a repeat

I usually put some loctite on mudguard bolts, stops them working loose and the blue type will help to reduce seizing as well even though that's not it's purpose. The best practice, as is often the case, is to service things regularly including removing, cleaning and replacing all the bolts.