Surface grinder bearing questions
 

Hi,

I just bought a Delta Toolmaker surface grinder that I'm refurbishing
for occasional hobby use. This is the older model with cast-iron
legs.

I have a coupe of questions regarding the spindle bearings on
this grinder.

The spindle is quite long and has a plain (i.e., no balls or
rollers) tapered bearing on the wheel end and a 'regular' ball
bearing on the pulley end. The ball bearing is sealed 'for life'
while the plain bearing is lubricated by a slinger that dips down
into a reservoir of oil.

I downloaded an owner's manual, and it calls for "High Grade Spindle
Oil of Viscosity 58 to 60 Saybolt at 100 degrees F." Am I correct
in translating this to "Mobil Velocite No. 6"? If so, that seems
like an awfully thin oil. I'm currently using Velocite No. 10
in my old plain-bearing lathe, and that's a pretty light oil.
No 6 is a couple of steps thinner.

Second question: I'm wondering how much end play the spindle
should have. The manual doesn't say (but does describe how to
make the adjustment). Remember that end play also affects bearing
clearance, since the bearing is tapered. The taper is fairly
shallow (a quick measurement of the drawing in the manual shows
about 8 degrees per side), so the amount of bearing clarence will
be much less than the end play.

Thanks for any information you can give me.

Dave

robinda *at* quincy.edu