I know I’ve seen such a chart, and I may actually be able to find
it.
In the meantime, you don’t actually need a chart, though I
understand if you’d like one. Just take your drill bit and hold the
end of it up to the end of the wire or tubing that you want to use.
This has always worked for me.
I’d suggest you check The Complete Metalsmith, Pocket Ref. I’ll
find my chart and get back to you.
Elaine
Elaine Luther
Metalsmith, Certified PMC Instructor
Hard to Find Tools for Metal Clay