On Sun, 21 Dec 2008 23:38:22 -0500, "Wild_Bill"
wrote:

I know there are some folks here that have considerable experience with high
speed parts and lubricating oils.
I anyone has recommendations for oils with properties suitable for high
speed bearings, I'd appreciate hearing them.

The spindle speeds in toolpost grinders can range from about 6k to 30k RPM.

I haven't taken them apart to see exactly what types of bearings are used in
the spindles, but I would expect them to be high precision ball bearing
assemblies. I've seen parts list prices of over $200 each for bearings with
ODs of about 1.25".

I presently have two brands, Themac 1/2 HP and Dumore 1/4 HP.


At those speeds, most bearings will be running with air/oil misting and
a very light turbine oil such as DTE Light

Cavitation becomes a real problem at high speeds in oil baths, as does
the fact that oil isnt a compressible and too much tends to make the
balls in the race ride up and over the oil droplets, slamming back down
on the other side.

The same effect that makes potholes on the back side of speed bumps.

Gunner

"They couldn't hit an elephant at this dist..."
Maj. Gen. John Sedgewick, killed by a sniper in 1864 at the battle of Spotsylvania