How to extract sheared off bolts

[PeterW]

I have two sheared off screws in the rear knuckle I would like to extract. They are the two 6x16 mm screws which hold the brake pipe bracket to the knuckle. Looks like the steel screws corroded and seized in the alloy knuckle. I know there are a few options - left hand drill bits, left hand extractors, drill it and retap ... etc.

Does anybody have any experience of the best way to extract these sheared off screws?

Thanks
Peter

[wixer]

Hi Peter,
I drilled and re-tapped all the ones that were sheared off on my car. I bought cobalt tipped drill bits from Axminster Tools and using a decent speed variable cord-less drill, it was easy. The most awkward thing was getting the drill into place and square. I coated the new bolts with anti-corrosion sealant called Duralac.

Hope this helps.

[Silver Surfer]

13072
You can try this.

SS

[UnhuZ]

^ it works... i have the 4 bit version !!

[PeterW]

^ it works... i have the 4 bit version !!
Interesting. Hadn't come across these before. Made from HSS, which should be tougher than normal left hand extractors - which have a reputation for breaking off leaving a bigger problem.
Thanks
Peter

[UnhuZ]

at least in mine, each bit is double sided/headed so you
use on side to make a cone hole in the screw head and
then use the other to get it out ;)