"Wild_Bill" wrote in message
...
Thank you, Ed. I've trimmed off the earlier discussion so that the
excellent summary is easier to see, since I expect that others will also
be interested in saving it.

I hope you find it useful, Bill.


IMO, it's not likely that someone could provide a clearer explanation,
although I suspect that there are still some HSMs that will disagree,
mainly just out of their inability/stubborness to accept clear reasoning.

The only possible exceptions that I can think of would be beginners that
can't properly select, grind or adjust their cutting tools, speeds and
feeds, and therefore assume that poor tool performance must be because
they don't have a coolant system.

That's what I'm trying to address. I think Iggy understands the issues, but
an implication was creeping in there that coolant is just better overall.
Actually, water-miscible coolant is a good solution for balancing several
competing demands, but the big ones just don't apply to hobby machining.


The others that earn their living making chips deserve to do whatever they
think is best for them.

Sure. And the cost equations that weigh all of these factors are the bread
and butter of industrial engineers, as well as some manufacturing engineers.
Commercial shop owners know about them but apply them somewhat unevenly.

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

Different things happen in different metalcutting speed/power realms. And
the hobby-shop realm has little to gain by applying techniques from the
higher-speed realms. Our relative cutting conditions dictate a whole
different set of solutions.

Some day we can talk about the realm above 10,000 sfm. That's where it
*really* gets interesting.

--
Ed Huntress