On 2013-06-06, Existential Angst wrote:
"rangerssuck" wrote in message
...
On Tuesday, June 4, 2013 11:21:20 PM UTC-4, DoN. Nichols wrote:

You'll probably also get a rather poor finish at such low speeds
with such small workpieces.

OK, I understand why 500rpm is too low to cut properly on small diameters,
but is it possible to increase the speed of this particular lathe? Is
there something about the drive or bearings that makes it impossible?

Proly could just change the motor speed (assuming the motor is not already
3600 rpm), and/or the drive pulleys. I'm sure the bearings could handle it,
altho it is generally true that the faster the rpm, the faster the wear.
Many lathes come with two-speed motors.

Note that there is a maximum speed rating for each chuck -- and
the larger the chuck, the lower that speed rating. At higher speeds,
centrifugal stresses can cause the chuck to turn into a collection of
Shrapnel flying in different directions.

Now -- if you have collets for the large lathe, you could
probably get away with speeding it up. But then you need to worry about
other workers not knowing about the speed limitations of the chucks,
and/or being too lazy to pull the chuck off and replace it with a much
smaller one, or a collet prior to running some high-speed cutting.

Maybe a smaller motor and spindle held in the big chuck could
give you high speed when you need it.

Enjoy,
DoN.

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