This is not going to be a productive night in the shop. The girls have
left me for the evening and I have to deal with the little extortionists
at the door. Before I gave up and went upstairs, I was trying to figure
out how to get the spindle lock assembly off. Presently the knob can be
pushed in a small amount, but not far enough to slide the dog into the
spindle. Any hints?
There's a setscrew on the bottom side. If you remove it (check for
two, don't remember), the bolt should pull out. I was not successful
in removing the mounting flange from the casting. The feedback from
the Yahoo group is no one else has removed it either. I gave up for
fear of cracking the pedestal casting.
Thanks, I found the setscrew hole under five generations of paint.
Pulled the bolt out to find the reason it does not engage is that the
holes in the bolt slide and spindle drive sleeve don't line up by about
~.075. I can find a single setscrew in the spindle drive sleeve. My
guess at the moment is that the fix is to loosen the setscrew and tap
the spindle drive sleeve into position. Is there a better procedure?
Then something's wrong. That spindle sleeve is in compression between
the rear bearing and front bearing races, and transfers the preload
from the clamp nut to the front bearings. Messing with the preload is
a big no-no if you have good bearings. Removing the pulley screw
would only allow you to shift the pulley and possibly pull the
spindle, which wouldn't help your alignment issue.
I'd check the spindle front cap. That's the only place you could
adjust the spindle front to back location in the column, probably with
One other uglier possibility is that someone backed off the clamp nut
on the back of the spindle, and the spindle shifted. If that's the
case, google "Gunner Hardinge spindle" for tips on proper procedure
for replacing the bearings, etc.
Oh, and if you need the manual and drawings, look in the files section
of the Yahoo Hardinge-Mill group.
Hmm. A puzzler. It's been some time since I had the spindle out of
my UM but I'm here perusing the exploded diagram. Looks like
the setscrew holds the three belt pulley to the spindle sleeve, or
maybe it holds it right to the spindle itself. Can't tell from the
The sleeve is indeed under compression from the rear clamp nut.
Further it looks like the sleeve itself has the sheave for the
power feed belt cut into its surface so there's no way that somebody
could have put it on the spindle backwards. (might be worth a double
check, to be sure that there's no V-belt groove on the sleeve, near
the triple pulley section. I think that one can put that sleeve
on the wrong way round...)
I would be interested to know which way the lock pin hole has
been offset - is the hole in the sleeve too close to the front, or
to the rear of the machine?
If for some reason somebody has put an incorrect part in the
machine, the spindle could be easily removed - the sleeve has
to come off to do this - and two new lockpin holes could be
machined into it, at 90 degrees to the other ones.
But I don't think Hardinge ever made that dimension (the
location of the locking pin) as a variable in their various
designs. That's the puzzler.
I would tend to dismiss out of hand the thought that the
spindle has been shifted. 0.075 inch of offset would make
the nose of the spindle behave wrong in some fashion.
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