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
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