South Bend 13" Lathe Bearing Issues - Page 3
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  1. #41
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    I don't see anything wrong yet, except in this photo, is the rear casting journal gouged?
    Or is the just angle of the photo?
    I gave a response post in the serial number thread on getting the photos from your phone rotated correctly to upload from you PC.

    Steve20210515_150322.jpg

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    When you say file the vee are you talking about the interface between the bearing and the expander? Or the v hump on the expander under the felt?

    And agreed I don’t see anything wrong, I’m starting to think your simply making the bearing adjustments too tight. But that’s just a guess.

    The screws that hold the expander into the cap MUST be snug (tight but DONT strip them)















    Hope these help in some way

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    Quote Originally Posted by swells View Post
    I don't see anything wrong yet, except in this photo, is the rear casting journal gouged?
    Or is the just angle of the photo?
    I gave a response post in the serial number thread on getting the photos from your phone rotated correctly to upload from you PC.

    Steve20210515_150322.jpg
    I did not see this Steve. I usually sit down when working on the lathe, I stand up to remove and install the spindle. I will have to look at this tomorrow. The spindle is in the headstock with the front bearing on but I removed the cap and put a spacer under the rear until I can look at it again. Thanks for helping with the photos.

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    That looks to be a reflection to me

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    [QUOTE=Homebrewblob;3758411]When you say file the vee are you talking about the interface between the bearing and the expander? Or the v hump on the expander under the felt?

    And agreed I don’t see anything wrong, I’m starting to think your simply making the bearing adjustments too tight. But that’s just a guess.

    The screws that hold the expander into the cap MUST be snug (tight but DONT strip them)


    Yes Sir it's the expander VEE at the felt location. I think I'm going to repair it back to the original VEE so I can go in steps if I need to. Yes again, the pictures and all helps. I have read the post on inserting pictures but can't seem to get it in my head about editing the rotation. I'll figure it out in due time.

    Was heat applied to the bronze shell?

    I want to respond to your other reply on the previous page, I have a lot of questions to ask.

    In Addition, I am totally screwed on owning a bore micrometer. I have been looking on eBay but in all honesty I don't know what I need. I can't afford very much either.

    If a member has a bore mic that he/she wants to sell please let me know.

    I bought a cheap scale that goes to 100 pounds pull for the lift test.

    On the bearing tightness I can assure you that I have not overtightened the cap or the expander. I have at times started with the rear bearing shims at 0.022 each side and brought it down removing 0.001 or 0.002 at a time to get to 0.0007 to 0.0015. Currently it's set to 0.005 but I no longer trust the lift test results because of my physical condition.

    Another thing is I did as SB recommended on filing the VEE and shortening the piece of felt on the expander.
    On the original spindle you could set it (spindle) in the headstock with the bearing caps off and still couldn't rotate it. At least I'm past that with the spindle I have now.

    Also as I mentioned in some of my first posts, the rear Allen Head Cap Screw on the inboard side was stripped. I had to run a tap through all of them and by doing so I was able to use 1 3/4" instead of 1 1/2" that came from SB. So I take great care not to overtighten that rear inboard Allen Head since it only has 1/4" of thread holding the bearing cap.
    Last edited by Greenlee52; 05-18-2021 at 11:08 AM. Reason: Missed a response

  6. #46
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    I wouldn't add a shim until you can prove it's actually out of center line, which I'm doubting it is.
    If you filed no more than 3/32 off the V for the felt, I would leave it at that. That just ensures it's not to tight.
    Or if you had a piece of F1 felt in it, might overcome the stiffer felt, maybe not. The shortening of it helps throw more oil out to the ends of the shells. The felt, remember, can't shear the film, it has to be soft enough to pass oil through it and also throw oil out into the shell. if its too hard of felt or compressed to much, it will shear the film, and eventual because of the loss of oil flow will overheat.
    Look at the old shells and try to see if there are any witness marks from the spindle over-heating and/or scoring. If it's oil flow problems I would expect to see the marks or discoloration on the front half of the shell facing the operator and possible more on the lower, as it runs out of oil after the wiper. On older box bearings, this would be on the rear upper from tool and belt pressure.

    I'd start with the full width peal shim pack thicknesses, but I can't remember what a 13-inch takes, and how many. The ones I have in my tool box are 16 or 17K, maybe Ted or someone that has a real shim pack can chime in hear and help. I'll keep looking for the spec if not.
    Anyway, git it shimmed up to make the spindle run free and not over-heat, first goal. then work on the lift test.
    Rotate the spindle multi time before the test, you want oil on the shells, zero your dial indicator and push down watching the indicator, note the reading where it stops moving, that's the downward force required to get to the oil film. Now pull up on the spindle until the dial stops moving as before and note the reading, and hopefully the are very close to the same movement. You can use a longer bar, you just have pull enough to know you have oil flat and the indicator will show where it bottoms . add the two clearance readings together and this is the total film clearance you have, South Bend states not more than .001, but not less that .0007 for a perfectly spec'ed spindle, I can't get mine quite to that, but I'm ok with that, it does everything I need it to do.

    Steve

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    Quote Originally Posted by swells View Post
    I don't see anything wrong yet, except in this photo, is the rear casting journal gouged?
    Or is the just angle of the photo?
    I gave a response post in the serial number thread on getting the photos from your phone rotated correctly to upload from you PC.

    Steve20210515_150322.jpg
    It was a reflection, I was able to remove the spindle again and wipe the headstock bearing castings clean and all was good.20210518_122024.jpg20210518_122002.jpg20210518_122010.jpg

    I read the serial number thread several times. I understand how to upload to this point but still can't see how to rotate. Sorry.

    I can see I messed up by not having the bearing wrapped and put in a box. The surfaces are scratched up pretty bad. How could I buff it out and not remove metal? What's the correct method to polish the spindle journal and not remove metal only smooth it out?

    The bearings were in a stainless pan with my tools needed for the job and they got beat up a lot.


    I don't know how I got the attachment with 2 pictures below, didn't see a way to delete it.
    Attached Thumbnails Attached Thumbnails 20210515_150637.jpg   20210515_150334.jpg  

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    For post #35....It might not be tonight but I want to discuss what you have posted, it's a lot of information and some of it I do not understand at the moment.

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    Quote Originally Posted by BobsYourUncl View Post
    I think you are heading down the right path with your observation that the rear cap was milled. The bores of the front and rear bearings must be concentric. If a cap was milled, it would shift the axis of the that bore away from concentric.
    You might consider measuring the concentricity of the rear cap bore to front cap bore.
    Quote Originally Posted by swells View Post
    I wouldn't add a shim until you can prove it's actually out of center line, which I'm doubting it is.
    If you filed no more than 3/32 off the V for the felt, I would leave it at that. That just ensures it's not to tight.
    Or if you had a piece of F1 felt in it, might overcome the stiffer felt, maybe not. The shortening of it helps throw more oil out to the ends of the shells. The felt, remember, can't shear the film, it has to be soft enough to pass oil through it and also throw oil out into the shell. if its too hard of felt or compressed to much, it will shear the film, and eventual because of the loss of oil flow will overheat.
    Look at the old shells and try to see if there are any witness marks from the spindle over-heating and/or scoring. If it's oil flow problems I would expect to see the marks or discoloration on the front half of the shell facing the operator and possible more on the lower, as it runs out of oil after the wiper. On older box bearings, this would be on the rear upper from tool and belt pressure.Attachment 321388

    I'd start with the full width peal shim pack thicknesses, but I can't remember what a 13-inch takes, and how many. The ones I have in my tool box are 16 or 17K, maybe Ted or someone that has a real shim pack can chime in hear and help. I'll keep looking for the spec if not.
    Anyway, git it shimmed up to make the spindle run free and not over-heat, first goal. then work on the lift test.
    Rotate the spindle multi time before the test, you want oil on the shells, zero your dial indicator and push down watching the indicator, note the reading where it stops moving, that's the downward force required to get to the oil film. Now pull up on the spindle until the dial stops moving as before and note the reading, and hopefully the are very close to the same movement. You can use a longer bar, you just have pull enough to know you have oil flat and the indicator will show where it bottoms . add the two clearance readings together and this is the total film clearance you have, South Bend states not more than .001, but not less that .0007 for a perfectly spec'ed spindle, I can't get mine quite to that, but I'm ok with that, it does everything I need it to do. Steve
    I'm going to measure the rear bore to the front bore. It will be 10 days before the scale I ordered comes in.
    I'm going to be on the lookout for a bore micrometer, I think it will be what I need to have accurate measurements. Using the Snap Gauge always seems to be close but out by .0005 to .0015 unless I take 5 measurements and average it out.

    I'm not sure what felt I have other than what came out of the kit sold on eBay. I didn't think about putting the felt in the center of the expander after I shortened it. I cut another full length piece of felt to go in. I really appreciate all of the explanations on how all of this works. I can picture the oil film coming up the backside and passing through the felt.

    The original bearing was shot and it was discolored, showed a lot of black.

    Do you think I should get rid of the shims I made and buy another shim pack? I'm using a large wooden dowel or rod that is 1 1/8" Diameter. Thank you for explaining

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    For the lift test you need metal bar of some kind to prevent bowing of the bar.

    I wrote my pass messages assuming you had a working machine, at this point I’m not really sure what’s going on.

    To be Frank your moving in all directions and i just can’t seem to make heads or tails of what all is going on.

    I think at this point you should just stop and evaluate.

    You have to have the felt at the top of the expander.

    If you have a Unmodified expander then USE THAT.

    DONT file any vee and DONT try to repair the vee.

    Order the southbend 13 shim pack off online if you haven’t, and install the whole pack.

    Do not remove any shims.

    Then do the bar test to see what your baseline is.

    After that record the baseline and then test run the spindle, DONT FORGET the top felt on the expander.

    If you ran the spindle without the top felt the bearings would overheat AND if you was at factory spec .007-.010 clearance the bearings could lock up when too hot.

    Report back here when you’ve done this, (a week, a month, doesn’t matter)

    Then we’ll have a much clearer picture.

    I’ve never heard of someone machining the headstock bearing caps/spindle bearing bore and I can see the hand scraping on your bearing caps/Headstock so it’s not been milled.

    If the bearings were burned up in its past life that could explain the shims on expander.

    There should NEVER be shims on the expander, that’s just bizarre.

  11. #51
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    Quote Originally Posted by Homebrewblob View Post
    For the lift test you need metal bar of some kind to prevent bowing of the bar.

    I wrote my pass messages assuming you had a working machine, at this point I’m not really sure what’s going on.

    To be Frank your moving in all directions and i just can’t seem to make heads or tails of what all is going on.

    I think at this point you should just stop and evaluate.

    You have to have the felt at the top of the expander.

    If you have a Unmodified expander then USE THAT.

    DONT file any vee and DONT try to repair the vee.

    Order the southbend 13 shim pack off online if you haven’t, and install the whole pack.

    Do not remove any shims.

    Then do the bar test to see what your baseline is.

    After that record the baseline and then test run the spindle, DONT FORGET the top felt on the expander.

    If you ran the spindle without the top felt the bearings would overheat AND if you was at factory spec .007-.010 clearance the bearings could lock up when too hot.

    Report back here when you’ve done this, (a week, a month, doesn’t matter)

    Then we’ll have a much clearer picture.

    I’ve never heard of someone machining the headstock bearing caps/spindle bearing bore and I can see the hand scraping on your bearing caps/Headstock so it’s not been milled.

    If the bearings were burned up in its past life that could explain the shims on expander.

    There should NEVER be shims on the expander, that’s just bizarre.
    I agree, I'm all over the place. I was trying to address everyone, every thread is important but it takes the line of thought in a different direction.

    This was a running machine. So I'll order another shim pack, I think without pealing any off it's about .032 thick. When you looked at my shims did you see something wrong about them that would help understand what's going on?

    The bore on the headstock and cap is all that's been machined. I guess when SB does this at the factory they have to account for the thickness of the shims prior to boring to make the bore round.

    Can anybody suggest or post a picture of the kind of Bore Gauge I should be looking for?

    I'll report back when I get a scale and a metal rod for the lift test and of course the shim pack. I will also go back to the beginning about the lathe history. Thanks

    I started thinking about this last night. Can anyone tell me the best method to polish the inside of my bearing shell to remove the scratches and also the spindle journal. What tools and what kind of compound will work the best? Thanks
    Last edited by Greenlee52; 05-20-2021 at 12:05 PM.

  12. #52
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    Quote Originally Posted by Homebrewblob View Post
    There a lot to read here.

    I rebuilt my SB16 and it has the same type of bearings.

    1)The using homemade shims in the tops of the expanders will cause the bearings to get TIGHTER (tighter tolerance) .

    Some one added shims to tighten up a worn/loose bearing

    If you remove the homemade shims then your bearing will expand and have a loose tolerance.

    2)Make sure the inboard and outboard factory SB shims are within .0005 - .001 of each other, the shim thickness on the right bearing vs left doesnt matter in relation to each other, only the inboard and outboard matter.

    3)Yes your top felt on the expander is a wiper and it pushes the oil to the gutters.

    4)Southbound Lists a process for adjusting the oil flow rate using THE TOP FELT on the expander.

    The thicker the felt the more oil wiped away and by capillary effect the more oil will get picked up off the capillary wick in the bottom.

    If (for example) you have no felt on the top then the oil logged bearing will not physically pick up additional oil from the bottom capillary wick.

    This will decrease heat removal (causing heat to build up) and also prevent debris from escaping the bearing

    And the contrary would be a top felt too tight will wipe away so much oil it floods the gutters and leaks out the side, sb says to file the expander hump a little at a time and test until the oil no longer overflows (leaks) from the gutters.

    Your spindle is locking up due to heat expansion.

    Your clearance is to tight. Your measurements are inaccurate and the oil clearance is too tight.

    Sounds like the bearings wore out so bad all the factory shims were removed but couldnt get the bearing tight enough.

    So they shimmed the expander DOWN to allow the bearing shell to clamp closed tighter (bringing the spindle into tight tolerance, may even have milled the flats on the bearing caps and then added factory shims to bring the bearing cap back up.


    I would remove the homemade shims altogether and then remove all the factory shims (HANDTIGHTEN the bearing cap bolts for this test as you can crush the bearing shells) and test the spindle play, afterwards if you have any play and/or can spin the spindle by hand then your bearing is technically shot.

    If the spindle is locked up thats a good sign, now with the expander shims removed, add back the factory shims until you free up the spindle, snug down the cap bolts And check play.

    Get your rear bearing around .0015 - .002 and test run it

    And you need to Absolutely make sure your measurements of the spindle play are CORRECT!

    iirc its a 60 or 80Lbs lift with a specific length very Rigid bar.

    Just drain and fill the Reservoirs, the capillary wicks will never allow debris to climb back into the bearings so dont worry, now bad oil will Climb.
    1) I added a couple of numbers to your statement to help me. With the homemade shims on top of the expander it will not let the shell spread out conforming to the wall making the bearing tighter, right?

    2)The laminated bearings seem to be more difficult to measure and I'm saying this from my point of view. There's more of a sponge reaction when trying to measure them. Does anyone else have this happening to them? It's no big deal but you have to remember that each one that peels off is supposed to be .002 so I'm thinking the glue is part of the problem. Is why you would crush them right off the bat?

    3)At least I'm correct on one thing. The felt is a wiper, I termed it a defuser as used in TIG welding to spread the gas out evenly out of the cup. Thanks for clearing it up.

    4)Can you please tell me where the information is from SB on controlling the oil flow with the felt on a expander or how to use the correct term for searching? I need to see this. Thanks

    I'll get back to this #35 after I get all the information together and the story straight and the parts in house. it should be 2 weeks or so.

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    1) the expander forces the bearing to expand to the bore when tightened. The shims determine the diameter of the bore.

    The bore is only round from factory and even then it’s not perfect.

    You don’t have to worry about how round the hole is.

    What I think happened is someone misunderstood how to adjust the bearings and in a bad attempt to adjust, shimmed down the expander to allow the bearing to clamp shut on the spindle *simulating a tighter bearing but this is NOT the proper way to adjust the bearings at all.

    To be honest I think if you would of just removed those weird EXPANDER shims you would of restored a useable clearance.

    The bearing shells CLAMP down on the spindle so tight the spindle won’t turn, the expander when tightened will spread the bearings open allowing the spindle to “free up”.

    The bearings are VERY rigid and return to the original shape kinda like spring steel.

    2) my shims where individually marked what size they are, once pealed apart they really shouldn’t be re used except under specific circumstances. And they were NOT all the same size!, you don’t measure the shims per se, you measure what you remove by reading what they are marked as.

    3) the felt does a little of everything, it also helps with “dry starts” by “storing” oil.

    4) I was incorrect I believe, it was the rebuilding manual from lion industries South Bend Lathe Works - Publication Reprints | VintageMachinery.org

    44e0e4f6-db32-40ec-b02b-3bddb56b4a2a.jpg

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    Quote Originally Posted by Homebrewblob View Post
    1) the expander forces the bearing to expand to the bore when tightened. The shims determine the diameter of the bore.

    The bore is only round from factory and even then it’s not perfect.

    You don’t have to worry about how round the hole is.

    What I think happened is someone misunderstood how to adjust the bearings and in a bad attempt to adjust, shimmed down the expander to allow the bearing to clamp shut on the spindle *simulating a tighter bearing but this is NOT the proper way to adjust the bearings at all.

    To be honest I think if you would of just removed those weird EXPANDER shims you would of restored a useable clearance.

    The bearing shells CLAMP down on the spindle so tight the spindle won’t turn, the expander when tightened will spread the bearings open allowing the spindle to “free up”.

    The bearings are VERY rigid and return to the original shape kinda like spring steel.

    2) my shims where individually marked what size they are, once pealed apart they really shouldn’t be re used except under specific circumstances. And they were NOT all the same size!, you don’t measure the shims per se, you measure what you remove by reading what they are marked as.

    3) the felt does a little of everything, it also helps with “dry starts” by “storing” oil.

    4) I was incorrect I believe, it was the rebuilding manual from lion industries South Bend Lathe Works - Publication Reprints | VintageMachinery.org

    44e0e4f6-db32-40ec-b02b-3bddb56b4a2a.jpg
    This is great information that explains so much as to the working of the expander and expander felt. When I get everything together in parts and new shims I can tell the rest of the story only a shorter version.

    All of the damage was already done by the previous owner who was a life long machinist selling one of his many lathes and other machinery.

    I heard it run for about 30 seconds, I wish I had tried out the other speeds on the step pulley but I didn't.

    Those are some first class shims you have in the picture.

  15. Likes Homebrewblob liked this post
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    Just remember you want a positive stop and snug on them expander screws, Ive heard of guys on here loosing them expander screws a tad to tighten the spindle and gain some better finish,

    But thats a horrible idea, loose expanders are a terrible terrible thing and could smoke the spindle at any moment.

    But they are steel screws in BRASS, so DO NOT EVER over-tighten them!
    They will strip right out

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    Quote- “I have at times started with the rear bearing shims at 0.022 each side and brought it down removing 0.001 or 0.002 at a time to get to 0.0007 to 0.0015. Currently it's set to 0.005” -

    I was checking back to this thread for updates and noticed this.

    The southbend recommendation for .0007 and .001 is NOT the shim thickness.

    It’s the measurement of movement in the spindle when lifted.

    There’s no shim thickness recommendation and everyone’s machine will have a different shim thickness/stack height.

    If your removing shims down to .001 or god forbid .0007 then your WAY WAY TOO TIGHT!!

    don’t do that!

    That’s your problem.

    Install the whole shim pack and reassemble then test spindle play.

    Rinse and repeat until your getting .0020 - .0015 movement in the spindle when lifting.

    If you wish to try and get down to factory spec i highly recommend stopping at .0020/.0015 first and running the lathe for awhile before making that jump.

    Keep the inboard and outboard shim stack equal, if you get the spindle too tight then add back shims equally until you get a useable clearance again.

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    Quote Originally Posted by Homebrewblob View Post
    Quote- I have at times started with the rear bearing shims at 0.022 each side and brought it down removing 0.001 or 0.002 at a time to get to 0.0007 to 0.0015. Currently it's set to 0.005 -

    I was checking back to this thread for updates and noticed this.

    The southbend recommendation for .0007 and .001 is NOT the shim thickness.

    Its the measurement of movement in the spindle when lifted.

    Theres no shim thickness recommendation and everyones machine will have a different shim thickness/stack height.

    If your removing shims down to .001 or god forbid .0007 then your WAY WAY TOO TIGHT!!

    dont do that!

    Thats your problem.

    Install the whole shim pack and reassemble then test spindle play.

    Rinse and repeat until your getting .0020 - .0015 movement in the spindle when lifting.

    If you wish to try and get down to factory spec i highly recommend stopping at .0020/.0015 first and running the lathe for awhile before making that jump.

    Keep the inboard and outboard shim stack equal, if you get the spindle too tight then add back shims equally until you get a useable clearance again.
    Well I'm close to getting started on installing all new parts as you all recommended. I have a new shim pack

    for each side front and back under the bearing cap. The thickness of each pack is 0.0325. On one side I see

    a thickness stamped on the shim, .001 but nothing on the reverse side. Could somebody please tell me the

    correct way to measure laminated shims??? It seems odd to me that even after I cut separate .002 or .001

    that they seem to be a half a thousands thicker than before I used them. My micrometers are on the money.

    Does the glue or bonding agent used have something to do with it? If I measure with a soft touch they are

    always thicker but I can tighten the micrometer and come up with what I think it should be eliminating the

    half thousands but is this giving me the correct thickness or screwing up what I think is the shim thickness

    with the lift test? I'm trying to learn the little details that are or seem to be extremely important.

    When I put the new packs in under the bearing cap they will all be the same at 0.0325 so I would expect a

    larger number on the gap for oil clearance. Do I peel off one shim at a time till I get in the ballpark?

    I can make additional shims from shim stock I bought from McMaster-Carr but I was reading that I should

    throw away the shims I peeled off and not to bother ironing them out flat?

    I have my new capillary oilers soaking in oil with a new piece of felt for the expander, it's now full

    length again across the expander opening opposite the VEE.

    Again I'm just trying to get all the right information together before I start. I don't think there is any

    out of round issues with the rear cap or headstock casting, it was all me in the way I was doing this. Not

    taking it apart and putting it pack together but in how I peeled off too many shims, didn't have the felt

    cut to the right length and using a 1-1/8" wooden round rod to push down and pull up getting the wrong

    results and wrong thickness on the test.

    It's amazing how well the larger front bearing works and is on the money every time but I could have gotten

    lucky on it. I'm getting my metal round rod cut to length tomorrow and I bought a scale that goes to 100

    pounds. I'll use a small mighty-mite come-a-long for the lift test and it will be more accurate. Thanks

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    The lift test does NOT require much force. You are only overcoming the oil film thickness. Do not overdo this.

    5-10 pounds applied via a broomstick is fine. Put the indicator (ideally a tenths reading one) RIGHT AT THE SPINDLE where it emerges from the
    headstock casting. Pull up, zero the dial. Push down, read the total indicator reading.

    Remove chucks, faceplates, etc - remove all tooling from the spindle. BTW slack the thrust bearing a teeny bit while doing this.

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    Quote Originally Posted by jim rozen View Post
    The lift test does NOT require much force. You are only overcoming the oil film thickness. Do not overdo this.

    5-10 pounds applied via a broomstick is fine. Put the indicator (ideally a tenths reading one) RIGHT AT THE SPINDLE where it emerges from the
    headstock casting. Pull up, zero the dial. Push down, read the total indicator reading.

    Remove chucks, faceplates, etc - remove all tooling from the spindle. BTW slack the thrust bearing a teeny bit while doing this.
    This is getting confusing and I don't want any of you to think I don't appreciate all the

    advice. I was told that I'm doing it all wrong using a wood dowel 1-1/8" and not pulling to

    at least 80 pounds. My strength to lift is probably about 30 pounds in the front and maybe 40

    pounds in the rear bearing. I bought a scale for the purpose of getting it right, now I don't

    need any of it because I was already in the limits I needed to be at. The only difference is

    I pushed down to zero out and then pulled up. You are the professional machinist so I empty

    everything I know and take in all that you suggest. Again I am thankful for ALL the

    suggestions passed on to me. I'll do the lift test as you suggested.


    What about the shims? Start out with the complete shim pack, 0.032+0.0005. Make sure it is

    all cleaned, oiled, and get started. IF the first lift test shows a large number like 0.015"

    should I continue to remove only 1 0.002" shim from the laminated stack or remove 2 or 3????

    I know what you are thinking, would I jump off a bridge if you told me too? lol

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    You cannot go wrong going slow by removing only one peel per try. The peels are two I think, and there's a 0.001 that you
    add or subtract.

    The lift test is easy, apply downward force until the dial gage stops moving. It's pretty obvious when you overcome the oil film. Zero
    the dial, then lift, again until the dial stops moving. I've never had to push real hard for this.


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