Wayne Lundberg wrote:

"mac" wrote in message
oups.com...

I just became the owner of a 13" LeBlond regal lathe the the number on
the ways is B 9860. The lathe seems to be in good shape, came out of a
trade school, everthing seems to be tight and the

---snip---

First thing... LeBlond was among the best of the best. Second thing: HP
labels have changed since then. I'm not sure, but I believe HP in the days
of your B9860 were calculated at 1,700 rpm and today's electric motors
calculated at 3,600? so it may be that your 3/4 HP is equivalent to today's
inflated 2HP or more.

It's not the speed that affects the horsepower. An induction motor can
be built to operate just shy of the line rate (60Hz = 3600 cycles per
second), or just shy of 1/2 the line rate, or just shy of 1/3 the line
rate, etc. So a two-pole two-phase induction motor will spin around
3500 RPM, a four-pole two-phase will spin around 1750 or 1700, etc.

Back in the day, however, motors tended to be rated _very_
conservatively, because everything was done with a slide rule and paper.
To make sure they were telling the truth they way over designed
things. This is why an older 3/4HP is "better" than a newer one.

And today's "2HP" for an itty bitty motor is just a lie -- see all of
the threads about compressors.

Older lathes have hand-scraped bearing surface ways and many of us old
timers think the hand-scraped ways are better than even the laser calibrated
ground ways of today's machinery.

I suspect that a hand-scraped way done with care is _way_ better than a
laser calibrated ground way done by someone who doesn't give a ****. I
also suspect, however, that a good, careful guy with a laser-guided
grinding setup that's kept in good trim can at least turn out stuff
that's as good as hand-scraped and probably faster.

The hottest-**** setup would probably be a laser interferometer plus a
really bright, committed guy with a scraper, though.

I'm probably wrong on both these counts... but they may be worth following
up on. LeBlond is one hell of a good lathe!

Wayne




--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com