On topic drilling question...
Drilling into the end of a large threaded rod, centered, punched and
drilled starting at 1/8" worked up to 3/8". 3/8" is about 1/4 of the
way into the hole and quit cutting, Either I hit a hard spot in the
steel, or it got work hardened, I was using coolant, but not flood.
Swapped to a new and sharp HSS bit, no joy at all.
Suggestions?
I can:
1. Try a masonry bit, 3/8 is something I have in the shop.
2. Heat it with a plumbers torch and see if I can temper the hole.
3. Go get a TiN or Cobalt bit...
I need to finish the 3/8 and then drill it to 13/32nds, then tap, so I'm
close, but I'm worried about the tap and the hard spot too.
Any help would be great!
Stuart
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