Replacing Lathe Spindle Bearings

[Jimmy Chrisawn]

A couple weeks ago it became necessary to replace the spindle bearings in my Jet 1642 after about 8 years of use. I searched for some good DIY information and found very little. Having a background in machine work and being pretty mechanically inclined I tackled the job. It wasn't really difficult. I did do a two part video on the process and I am goimg to post a link in this post. Maybe it will be helpful. The process works with other lathes not just the Jet. It is what I did and how it worked for me, so I just hope it helps.

https://www.youtube.com/channel/UCdF...7HDJ4U5XoxFH7g

[Scott Ticknor]

I wish all repair videos were this good, Thank You !

[Thom Sturgill]

Nate Davey posted a thread back in 2010 on replacing the bearings: http://www.sawmillcreek.org/showthre...nt-on-Jet-1642.
I used his info to replace mine - twice, once just recently.

[David Gilbert]

I love videos like this. I seriously considered replacing the bearings on my Jet 1642 but sold it before I got around to it. Very nice job.

Cheers,
David

[Jimmy Chrisawn]

Nate Davey posted a thread back in 2010 on replacing the bearings: http://www.sawmillcreek.org/showthre...nt-on-Jet-1642.
I used his info to replace mine - twice, once just recently.

Thank you Thom, I followed the link in your reply, but wasn't able to find the actual write up. I would le to read it sometime. Jim

[Jimmy Chrisawn]

Thank you David, I hope it is helpful to someone along the way. Jim

[Brice Rogers]

I want to thank the OP for posting the link to the Youtube video. It is helpful.

I have 6 month old Grizzly G0766 with a bad spindle. I'm hoping that Grizzly can make me a new spindle with both nice looking threads and threads that are within the National size spec. So, I am optimistic and anticipating swapping out the spindle in a short time and am planning on replacing the bearings at the same time.

Is the procedure for replacing the Grizzly G0766 bearings basically the same as were shown in the Youtube video for the Jet lathe? What are the differences, if any?

[Jimmy Chrisawn]

I want to thank the OP for posting the link to the Youtube video. It is helpful.

I have 6 month old Grizzly G0766 with a bad spindle. I'm hoping that Grizzly can make me a new spindle with both nice looking threads and threads that are within the National size spec. So, I am optimistic and anticipating swapping out the spindle in a short time and am planning on replacing the bearings at the same time.

Is the procedure for replacing the Grizzly G0766 bearings basically the same as were shown in the Youtube video for the Jet lathe? What are the differences, if any?

Brice, the procedure is basically the same. The one thing that may be different is the way the Grizzly monitors the spindle speed. Where the Jet uses four bolt heads the Grizzly may use a collar type pickup.

[David C. Roseman]

Brice, I just watched the first part of the Youtube video on the Jet 1642. I haven't had to replace spindle bearings on the Grizzly G0766 (or my older G0733), but I can tell you that there are some differences from the Jet that require modifying the procedure. Example, the rear bearing in the Jet is seated in a collar outboard of the spindle pulley. In the G0766, it is inboard of the spindle pulley, seated in the main part of the casting that also holds the nose bearing. The Jet video shows driving the spindle out while the pulley and its key are still on, until the pulley dislodges against the headstock casting. That makes me wince. On the Grizzly, I definitely would first remove the pulley, using a bolt-type wheel puller. $15 at HF, if you don't already have one: http://www.harborfreight.com/bolt-ty...set-69889.html

To Jimmy's point about the rpm sensors, the Jet uses an optical sensor in the sending unit. The Grizzly G0766 uses an electromagnetic sending unit that monitors the rotation of three rare-earth button magnets embedded in the inboard face of the spindle pulley. The sending unit mounts in a bracket (ref. #47 in the G0766 parts list) that attaches to the headstock casting just aft of the rear bearing collar with two Phillips pan-head screws. From the parts diagram, it doesn't look like the sending unit or the bracket would need to be removed to pull the spindle and bearings. You may know all this already.

Another thing that just occurred to me. The button magnets are pressed, not glued, into the spindle pulley, and they are directional. That's another reason to pull the pulley gently, rather than driving it off, which easily could dislodge them. If they do become dislodged, make sure they go back in the same polar orientation. If the poles of one are reversed, for example, the sensor will not read it as it rotates, and rpm display will read at only 2/3 of actual speed.

[Brice Rogers]

Thanks, David.

[Steven Park]

After reading and researching, I still have trouble taking out the spindle on my g0766. Does the spindle come out the front of the head stock or the back? Do I just wack on it like in the jet video? How hard should it be hit? Any advice

[Dexter Harris]

I replaced spindle and bearings in my go733 acouple of months agp. Lucky for me, my son in law is a machinest for a living. He knew just what to do. Turn a spindle to drive it out from the back and yes I had to hit it very hard many times.

[Steven Park]

I replaced spindle and bearings in my go733 acouple of months agp. Lucky for me, my son in law is a machinest for a living. He knew just what to do. Turn a spindle to drive it out from the back and yes I had to hit it very hard many times.

So you just hit it with a soft hammer from the back and it pops out the front?

[Alex Zeller]

I'm assuming you have the nut and pulley off of the back. If so then I would get a good solid piece of hardwood and hit on that. Hopefully the wood will be strong enough and not splinter.

[Steven Park]

I'm assuming you have the nut and pulley off of the back. If so then I would get a good solid piece of hardwood and hit on that. Hopefully the wood will be strong enough and not splinter.

yeah, everything is off of the spindle... i just feel nervous hitting the thing.... seems very sketchy.