Re: [CAD_CAM_EDM_DRO] Cheap 56,000RPM milling upgrade (not a dremel :)

JanRwl@... wrote:

>In a message dated 4/17/2005 12:59:30 A.M. Central Daylight Time,
>elson@... writes:
>
>I've got a Westwind air bearing drilling spindle that runs on 80 V @ 400 Hz,
>or 160 V @ 800 Hz if I had a VFD that would go that high. This motor uses
>about 3-4 CFM of air, almost all for cooling the motor.<<
>So, WHICH is it, high-freq. AC in, or AIR? If both, does the air "turn"
>anything, or is that JUST for cooling and swarf-blast? JRR
>
>

It is a high frequency AC induction motor, but uses air for the bearings
(both radial
and thrust) as well as air cooling of the motor. When you turn on the
air, the spindle
begins to float, and if you flip it with your fingers, it will spin for
minutes. There isn't
a whole lot of swarf, this thing is mostly for drilling tiny holes in PC
board material.
They usually set up a shop vac to vacuum away the dust. The air escapes
from the
top of the motor, where the thrust bearing is.

Jon