Quote:
Originally Posted by LouisianaJoe
I have used vinegar on rusty tools to dissolve the rust. I restored a very old hand saw this way. Make sure you rinse it good after use.
Another option is to drill out the screw with a bit that has a slightly larger size than the screw threads. Then tap new threads and use a larger screw to attach the new stuff.
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I think the screws are beyond remediation now. As to re-drilling & tapping one size larger, that would mean probably 5/16" (or metric
) plus drilling out the jaw plates (which
just pass a 1/4" screw) and they are really hard, R58-60 according to the places in the UK that make new ones over there. I'd prob. need cobalt chucking reamers to enlarge them.
I've drilled out one jaw and even the thin fragments of the old screws are being recalcitrant. I may be able to re-tap over them or use a #7 bit to clear out the remnants before retapping. I have to make sure that the new hole/threads are
exactly where the originals were, though. I may be able to clamp the old jaw plate in place to act as a guide.
This is more work than I had anticipated, but as long as I learn something useful, it's not time wasted. At least that's what I'm telling myself...