RPM is set for surface speed to cut with. Large diameters have more
surface speed - inches/minute.

cutting steel or brass depends on the correct setup.

Martin

On 8/21/2017 7:25 PM, wrote:
On Mon, 21 Aug 2017 10:52:57 -0700, "Bob La Londe"
wrote:

Is there a speed you just routinely find yourself using most of the time?

As I've said many times. I'm not a "real" machinist. I just play one on
the Internet, and I get paid for some work in a very narrow specialty.

Calculate the cutting speed :-) Turning an item, say a foot in
diameter, requires a noticeably different speed than turning a 1/2"
shaft :-)

--
Cheers,

Schweik