On 2015-05-23, Ed Huntress wrote:
On Fri, 22 May 2015 20:40:21 -0500, Ignoramus8699
wrote:

On 2015-05-23, Ed Huntress wrote:
On Fri, 22 May 2015 20:26:10 -0500, Karl Townsend
wrote:

Its a shame, that low top speed on the Monarch is a killer. that's why
it has no wear. I'd send it on down the road.

Slow speed has been the Achilles' heel of Monarchs for decades. They
are magnificent machine tools -- one of the best representations of
American machine tool design. But they were made for HSS tooling.

I don't know what the speed of Iggy's machine should be, but even if
it's running at its top designed speed, if it's from 1944, it will be
slow.


It is 500 RPM.

Ed, can you explain what is so bad, other than more time spent
machining, about slow top speed?

i

That's it, Iggy -- more time spent machining.

These are commercial machine tools. The objective is to produce
quality parts at the lowest cost. That means, first, the shortest
part-to-part cycle time. Then you factor in the tooling cost;
generally speaking, running tools faster wears them out at a faster
rate. In other words, they last for fewer parts.

Running those two curves in an equation -- cycle time and tool life --
is the traditional way of optimizing cost-per-part. Today's
multi-coated tools confound the simple curves a bit, because some of
them, particularly those with an aluminum-oxide top coat, or a
lubricating top coat of molybdemum disulfide over aluminum oxide, need
to run very hot to perform well.

In general, though, with the tools we use in hobby work and in most
general machine-shop work, the only thing you lose by running slower
is time. There are some exceptions regarding surface finish, where
faster can be better, but that's the general rule.


OK, then I am keeping the Monarch!

i