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Jimmy Chrisawn
03-13-2016, 5:42 PM
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/UCdFaZ0aX47HDJ4U5XoxFH7g

Scott Ticknor
03-15-2016, 3:39 PM
I wish all repair videos were this good, Thank You !

Thom Sturgill
03-15-2016, 5:41 PM
Nate Davey posted a thread back in 2010 on replacing the bearings: http://www.sawmillcreek.org/showthread.php?155617-Bearing-Replacement-on-Jet-1642.
I used his info to replace mine - twice, once just recently.

David Gilbert
03-16-2016, 3:58 PM
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
03-16-2016, 7:58 PM
Nate Davey posted a thread back in 2010 on replacing the bearings: http://www.sawmillcreek.org/showthread.php?155617-Bearing-Replacement-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
03-16-2016, 7:59 PM
Thank you David, I hope it is helpful to someone along the way. Jim

Brice Rogers
03-16-2016, 11:47 PM
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
03-19-2016, 6:19 PM
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
03-20-2016, 2:56 PM
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-type-wheel-puller-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
03-20-2016, 3:52 PM
Thanks, David.

Steven Park
08-28-2018, 12:39 AM
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
08-28-2018, 10:40 AM
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
08-28-2018, 11:53 AM
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
08-28-2018, 1:27 PM
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
08-28-2018, 1:38 PM
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.

david privett
08-28-2018, 3:00 PM
you can always use a nut over the threads and a big brass mallet or maybe a deadblow , when I did mine it was on there pretty good when reassembled used some grease on all the surfaces inner and outer.

Joe Kaufman
08-28-2018, 4:52 PM
Use allthread through the spindle and wood blocks to pull the spindle out and back in for a bearing change or if you have to change the belt. Makes the job much easier on a Powermatic Lathe with the double bearings. I can't locate the photo's right now.

Barry McFadden
08-29-2018, 2:10 PM
Does anyone realize that this thread is over 2 years old??

Len Mullin
08-29-2018, 4:37 PM
Well as long as the info is still correct on the subject, it shouldn't make any difference how old the posting is.



Does anyone realize that this thread is over 2 years old??

Barry McFadden
08-29-2018, 8:43 PM
Well as long as the info is still correct on the subject, it shouldn't make any difference how old the posting is.

I would figure that the OP has it handled and doesn't really need any more help at this point...

Alex Zeller
08-30-2018, 12:36 PM
I would figure that the OP has it handled and doesn't really need any more help at this point...

There was a new post about a Grizzly lathe from a few days ago. That's what people are answering.

Barry McFadden
08-30-2018, 5:56 PM
There was a new post about a Grizzly lathe from a few days ago. That's what people are answering.

OK......... puzzling why they would answer a Grizzly thread in a Jet thread???