Enco 9x20 Spindle Bearings Reading Every Second Revolution O

[ronzo]

I have an Enco 9x20 lathe. Ever since I got it I haven't been able to indicate anything dead true because I get a high point of about.001 on every second revolution of the spindle. I've just lived with it but now it's getting old.To me this says bad spindle bearing as a high roller or ball would make a complete revolution every second revolution of the spindle.
Any thoughts on this?
Any advise on replacing the bearings?
Thanks
Ron

 

[fixit]

I have an Enco 9x20 lathe. Ever since I got it I haven't been able to indicate anything dead true because I get a high point of about.001 on every second revolution of the spindle. I've just lived with it but now it's getting old.To me this says bad spindle bearing as a high roller or ball would make a complete revolution every second revolution of the spindle.
Any thoughts on this?
Any advise on replacing the bearings?
Thanks
Ron

interesting, very interesting

 

[shootur44]

interesting, very interesting

I also have a ENCO 9x20 and had the exact same problem and tried every update I could find and still had that and a laddering effect on my finish that I could not get out and I finally replaced the two main shaft bearings and now it's fantastitic. I can actually hold a 3/10 over 16 inch span now and my buddy says it's better than his 13 x 40 can hold so I guess I am pleased.

 

[gt40]

I have upgraded the spindle bearings on my PM45 mill and looked into it on the lathe- it isn't that terrible but you need to understand how your lathe's spindle is setup and how to press fit bearing. Not that big of a deal actually but there are certain principles you need to apply like applying even force on the inside and outside of the bearings while installing them. Properly done, it can be a huge upgrade. Before you go down that rabbit hole though, you want to be sure the spindle itself has run out and not the chuck or something else. How are you measuring things?

 

[ronzo]

I have upgraded the spindle bearings on my PM45 mill and looked into it on the lathe- it isn't that terrible but you need to understand how your lathe's spindle is setup and how to press fit bearing. Not that big of a deal actually but there are certain principles you need to apply like applying even force on the inside and outside of the bearings while installing them. Properly done, it can be a huge upgrade. Before you go down that rabbit hole though, you want to be sure the spindle itself has run out and not the chuck or something else. How are you measuring things?

Thanks.
I have checked with work held in 3-jaw, 4-jaw chucks, & collets all the same. Have also checked the spindle itself using a DTI It's definitely the spindle. I can turn a piece and then indicate it and get the same effect.
Will I need a puller to get the old bearings off? Do I need to heat the bearings to install or remove?
Ron

 

[gt40]

Thanks.
I have checked with work held in 3-jaw, 4-jaw chucks, & collets all the same. Have also checked the spindle itself using a DTI It's definitely the spindle. I can turn a piece and then indicate it and get the same effect.
Will I need a puller to get the old bearings off? Do I need to heat the bearings to install or remove?
Ron

I think how you do it depends on the design a bit. I used a piece of aluminum stock like this and a long piece of pipe:

The donut just clears the the spindle and supports the bearing and the long piece of pipe allows you to put force on it.



As far as heating, you do that during the install not the removal- not sure how to only heat the bearings and not the spindle tube. Basic idea is chill the spindle and warm the bearing, slide it on and then you have a tight fit when it normalizes temp. You don't want over heat the bearings though...

Hope this helps and good luck!

 

[ronzo]

I think how you do it depends on the design a bit. I used a piece of aluminum stock like this and a long piece of pipe:

The donut just clears the the spindle and supports the bearing and the long piece of pipe allows you to put force on it.



As far as heating, you do that during the install not the removal- not sure how to only heat the bearings and not the spindle tube. Basic idea is chill the spindle and warm the bearing, slide it on and then you have a tight fit when it normalizes temp. You don't want over heat the bearings though...

Hope this helps and good luck

 

[ronzo]

Thanks you have bolstered my confidence. I'll order the bearings in the morning.

 

[cvarrin]

There are two PDFs on the web that deal with chaining the bearings / spindle on 9x20 lathes. "Rebuilding the Asian 9x20 Late" by Cletus L. Berkely and another with no author on it (at least my copy) with the file name: "ReplacingSpindleBearings.pdf"

 

[ronzo]

Got 'er. done.
I got the SKF bearibgs fron Enco. There were two stages where I almost abandoned the job. One in the very beginning, using a 5/8" threaded rod with a 3ft. long pipe on the handle of a 12" adjustable wrench the spindle wouldn't let go. Only after a solid "whunp" with a dead-blow hammer on the end of the spindle di it finally crack. Then alternating between torquing it and "whumping" I finally got it out.
The second time was when I tried to remove the inner race from the riht side of the spindle. Nothing and I mean nothing could persuade it to let go. I finally cut the race with a cutoff wheel in my Dremel almost to the journal and then split it open with a cold chisel to spread it. They make these things way, way, WAY too tight.
There was no mfr's. name on the old bearings. I guess there is a reason for that. With help of my handy-dandy mini lathe I reduced the size of the left hand journal about .0005" to a nice "push" fit on the bearing and the right hand journal about .0012 from the right journal for a light interference fit. It went togeteher without a hitch and the lathe now functions beautifully.
Thanks to all for your help.
Ron