Nasty, nasty, nasty.
I hope someone comes to your aid. I had a situation like this occur in our
prototype machine shop. As the work was being bored for tapping, our continuos
oil spray was apparently hardening it. The tap went in maybe 1/2", began to get
very tight, finally seized and snapped when we tried to remove it. Had to junk
the whole thing and start over.
I have a friend who is a tool and die maker at FoMoCo, a very skilled welder, a
great no-plastic body man, and of course an MG nut. He is not on the net, so if
you don't get some real help right-quick, send a note to me and I'll ask him
for some advise. He doesn't always like to share what he knows, and that is
unfortunate because he knows a lot.
If you encounter stripped threads again, be advised thread repair kits are
pretty inexpensive especially compared to this.
Jim
abadeker@tribune.com wrote:
> Listers:
> After the crazy itinerant welder stopped by and welded shut the
> stripped stud holes on my A's front shock mount (not the job I hired
> him for, but never mind), I've been trying to drill them out and retap
> them. One I succeeded with, starting small and working my way up to
> 5/16. But the second has me stopped: I got a 1/4-inch cobalt bit
> through, but can't step up to a 5/16th, surprisingly; it went in about
> 1/16 inch and just sits there, spinning and no doubt making the whole
> problem worse by heat-treating the already very hard metal. I bought
> another 5/16 cobalt bit, thinking I had dulled the other, but no soap.
> I don't have a torch (aside from propane) to anneal the area, even if
> that would work. I can't get at it from underneath; it's the inboard
> hole and is blocked by the rest of the frame. I'm thinking of slipping
> a narrow cold chisel down onto the `collar' created by the shallow
> penetration of the 5/16th bit and giving a tap, in hopes of creating a
> ridge or chip for the bit to get hold of.
> Any better suggestions?
> Thanks,
> Andy Badeker
> '60 coupe
|