Thread: DV-59 Bearing Change

I'm trying to change the spindle bearings on a DV-59 and am running into trouble getting the nut off the back of the spindle. THe pin holes have been egged out to the point that I have to use a hammer and a pin punch and I don;t know if it is a left or right hand thread. I've banged it about a quarter of an inch either way and notice no difference in movement.

Please help me on this one if you can. I don't want to mess this one up for the obvious reasons.

Geoff

My split-bed ESM-59 had the nut as standard,
right hand fastner. It was hella tight though,
I had to make up a special wrench to undo it.

I had to hold the special pin wrench (face
spanner, really) onto the nut with the outer
nut that held on the spindle locking ring
that the lock pin engaged.

The trouble with that designe was, you could
not get at the preload nut (the one you are
into) without *first* removing the ability to
lock the spindle.

What WERE they thinking???????????????

That problem was fixed in the DV series machines
I think because the lock pin engages the
preload cylinder at midpoint of the headstock.
So you can at least lock the spindle.

But the wrench to undo the preload nut will
have to be about three feet long, that's what
I got up to before mine budged. I was locking
the spindle with driver plate on the front,
I sheared the pin on that twice during the
exercise.

Spend as much time as you need to fabricate the
absolute best four-pin face spanner you can
figure out. Use something to tie it in hard
to the nut, even if you only use a piece of
threaded rod through the spindle, so it cannot
cam out.

Good luck.

Jim

I had the same problem with my ESM-59. To get the clamp nut off, I made a tool with four pins. However, the only tool I had that fit on the spindle nose was a step collet closer, so I had no easy way to hold the spindle still while loosening the nut. I wound up removing the headstock a grabbing the collet closer with the chuck on another lathe. Then I was able to loosen the nut. It was right handed and tight, but no so tight as the one Jim Rozen described.

I tried a pin punch and hammer first, but there was no way that was going to work.

Intersting. I guess somebody else found the
same hardinge 'feature' that I did.

I used a driver plate, which has a slot across
the front, for the dog to engage in, but I
simply put a two foot long piece of rectangular
stock across the slot and braced that against
the bed, cushioned with rags.

Like I said, I sheared the pin twice while
undoing that nut.

I was only going into the headstock as far
as I had to, to get some grease in there. The
machine had an intermittent bearing whine that
sounded like it might be from the grease being
old and dried out, the machine sat for many
years unused.

I only extracted the spindle out far enough
from the front so I could get a syringe into
the two front bearings to inject a bit more
grease. It seemed to help a lot.

I was worried about getting the old bearings
back in with the alignment marks, if any,
back in the same spot. I've heard tell those
bearing go in with dots or marks that should
be lined up, and I knew mine were in there
from the factory, correctly. So I tried to
disturb it all as little as possible.

Jim