Joe Gwinn fired this volley in
:

I bet if he had used flood coolant, far less resharpening would have
been required.

Or just taken pecks no more than a drill diameter before re-lubing. I saw
him cut more than an inch in dry metal more than twice. I also saw him
pause in the drilling (just one or two times), which kills the hell out of
bits and work-hardens the surface.

Lloyd