"Don Foreman" wrote in message
...
snip
A hole saw with plenty of cutting fluid will be the lowest-torque
approach. Next would be a step bit, last choice would be a 1" dia
twist drill. The twist drill would be better for production rate in
heavier material with suitable machinery driving it, but hole saws and
step drills (unibit) work much better when the dia of the hole is
considerably larger than the thickness of the material.

Exactly.

In spite of my suggestion, earlier, to follow the drilled hole with a
reamer, I would use a hole saw, assuming I could get one that created a hole
in keeping with my needs. They tend to cut a ragged hole until they self
pilot.

In answer to the concept of water allowing a greater surface speed, while
coolant keeps temperature under control, it has little effect of the cutting
edge. If you run too fast, the cutting edge overheats and burns, in spite
of being cooled. Surface speed must be reduced, or tools that can
withstand greater surface speed would be required.

Harold