> I'll need to remove two bolts broken off in the block of my old Volvo,
> and would appreciate any recommendations or advice from those of you who
> have gone before. I've removed broken bolts before by cutting a slot for
> a screwdriver but these are both a thread or two deep into the block.
> What else works? What doesn't?
There was a fairly extensive article on this topic in Home Shop Machinist
(or maybe Projects in Metal, I get the two confused). The author said
welding a nut to the broken bolt/stud was the only way to go. For cases
where the bolt was broken below the surface, he drilled a sacrificial bolt
and screwed it into the exposed threads, then welded through the hole.
Apparently both the heat of welding and the current involved tends to free
the threads, and there's no expansion of the bolt like there can be with
ordinary extractors. Also no need to precision drill in what may be an
awkward position.
Randall
|