Newbies Lathes

[ozzie46]

Here are some pics of my Grizzly 10 x 22. I made quick change tool post for the Griz.











Works like a charm.

Ron

 

[ozzie46]

Make sure your oil ports for the spindle are clean and free of cast iron dust and such. Here's what I found.









I had only run it in at this point. Oil ports full of black grit. With the bearings out they flushed clean easily.

Grizzly sent me new bearings and I installed them. After I had done that I read on Yahoo 10x 22 group that I should have polished the spindle some as the bearings are to tight of a fit. But I had it back together already and after 2 years I have had no problems with the bearings.

Ron

 

[ozzie46]

Thanks dalee. Yes it is a great improvement over the stock 4 way. I also plan on redoing the compound mount, making it a 4 bolt mount instead of 2 bolts.

Ron

 

[ozzie46]

Oil coming out from the bearings is normal if you oil too much. They are not sealed bearings so nothing there to keep oil in. I usually squirt twice with my oil can and go on,the oil doesn't come out then, if I squirt 3 or more times oil will come out. I oil it every time I start up for the day. The oil does get in the bearings as I can see it come out from between the rollers if I over oil it. You can see it behind the chuck mount.

As far as tear down you need a couple of spanner wrenches for the spanner type lock nuts on the spindle
and access to a press and bearing pullers to do the job right. I so angry at what I found I just pulled off the nuts and gears and beat the spindle out with 2 x 4 board carefully so it didn't drop on the ways. Then as the bearings were shot any way I beat them off with punch. I don't recommend this approach . Then it is a matter of replacing the races in the head stock and the bearings on the spindle and putting things back together. Remember to adjust the bearing preload also. That is the reason for polishing the spindle so the bearings aren't such a tight fit on it. They should slide on with no play like wheel bearings on a car.

Work carefully and things will be fine.

Ron

 

[Highpower]

~ Then it is a matter of replacing the races in the head stock and the bearings on the spindle and putting things back together. Remember to adjust the bearing preload also. That is the reason for polishing the spindle so the bearings aren't such a tight fit on it. They should slide on with no play like wheel bearings on a car.

Ron

Ron,
I don't know anything about this lathe, but I have to question the notion of using a slip fit on spindle bearings? Any clearance between the spindle and bearing race will certainly show up at the workpiece when a cutting force is applied. I can understand perhaps a slight interference fit at the drive end, but I would have thought a press fit would be necessary at the chuck end at least?

Keep in mind I haven't replaced any lathe spindle bearings before, so I'm certainly no authority on the subject. :-[
But I have rebuilt plenty of transmissions & differentials in my time and have never seen a drive pinion that didn't have a pressed bearing on the business end where all the force is applied. I would just hate to see anyone end up with run out or vibration problems at the chuck after having installed a fresh set of bearings.

 

[Tony Wells]

Slip fit in this case is likely no more than 0.0002. The clearances in the bearings themselves are also part of the necessary calculations. The problem and difficulty here is in temperature coefficients. The spindle will grow when it reaches operating temperature, but that generally comes from the bearings, which also change size as they run. The idea is to strike a compromise with as low a clearance as possible when cold, and not too little clearance when warm to allow an oil film. When things warm up, and everything is sized theoretically perfectly, all there is room for is oil.....no clearance other than that. The bearing will "shrink" onto the spindle and there will be no clearance there.

Kind of like old tube radios.....they drift until temperature stabilized, but until then they are still usable.

 

[ozzie46]

Slip fit in this case is likely no more than 0.0002. The clearances in the bearings themselves are also part of the necessary calculations. The problem and difficulty here is in temperature coefficients. The spindle will grow when it reaches operating temperature, but that generally comes from the bearings, which also change size as they run. The idea is to strike a compromise with as low a clearance as possible when cold, and not too little clearance when warm to allow an oil film. When things warm up, and everything is sized theoretically perfectly, all there is room for is oil.....no clearance other than that. The bearing will "shrink" onto the spindle and there will be no clearance there.

Kind of like old tube radios.....they drift until temperature stabilized, but until then they are still usable.

That's what I've been told also and and also don't forget the bearing preload.
Old machinists will tell you not to expect to hold tolerances until the machine is well warmed up.

Ron

 

[ozzie46]

Turbo,

The spindle comes out toward the tail stock as the spindle flange for chuck and face plate mounting is to large to pass through the head stock.

Ron

 

[ozzie46]

I didn't measure the torque.
I was a mechanic for many years and developed a good feel for how tight a wheel bearing should be and used that. It seems to have worked as I have had no problems and have done some heavy turning on the lathe. As they say time will tell but so far so good.

As far as a repair manual I don't know if Griz has one or not.

Ron

 

[Highpower]

Slip fit in this case is likely no more than 0.0002.

Ahhhh..... Ok. That makes much more sense than what I was thinking. :-[

Thanks for the correction Tony. My bad.