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Acceptable spindle play, Logan 825 10” lathe

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  • Acceptable spindle play, Logan 825 10” lathe

    I’m finding it almost impossible to part off with my Logan 825 10” lathe. The work seems to climb up on the tool. I set up a dial indicator on the chuck and found it will lift by .005” when the spindle is static, when I’m trying to part off with a normal top pressure the spindle lifts by .008” I’m just wondering if I need to replace the spindle bearings?

    I removed the spindle and cleaned and regreased both spindle bearings about a year ago. The grease was dried out then and not doing any lubricating.

    Has anyone found the bearing numbers for this lathe? So I can get them locally.
    Last edited by RockingJ; 02-07-2019, 06:17 PM. Reason: Because I wanted to!

  • #2
    the bearings are still available from logan actuator company. you must tighten the spindle nut very tight. it's on the inside of the head stock. I used a punch and hammer.
    http://store.lathe.com/baandoibe.html

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    • #3
      I think they are special, pre-loaded, or assembled with precise parts to have about 0 play. I don't know though if they are an odd size though, you may be able to get them locally or you need to contact Logan Actuator.

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      • #4
        Originally posted by wdtom44 View Post
        I think they are special, pre-loaded, or assembled with precise parts to have about 0 play. I don't know though if they are an odd size though, you may be able to get them locally or you need to contact Logan Actuator.
        they are, special that is. and I think they are special made for logan.

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        • #5
          I know I can get them from Logan. I’m just wondering if there is another source. I’m retired and Logan’s price is a bit high for me! And I’m not sure this will fix my issues.

          There is maybe .002 thousands end play on the spindle, bearings feel smooth, but this lathe is 74 yrs old.

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          • #6
            Originally posted by RockingJ View Post
            I know I can get them from Logan. I’m just wondering if there is another source. I’m retired and Logan’s price is a bit high for me! And I’m not sure this will fix my issues.

            There is maybe .002 thousands end play on the spindle, bearings feel smooth, but this lathe is 74 yrs old.
            no other source that I could find. try the adjustment. my lathe is 73 and has no play.

            Comment


            • #7
              8 thou in the spindle bearing is just about IMPOSSIBLE. It would have had to have been lubricated with diamond dust for that to ever occur. Almost certainly that issue is elsewhere.

              First, make CERTAIN that the problem really is the spindle moving, and not the headstock or something else. Put the indicator base on the HEADSTOCK and repeat your check, measuring to the actual SPINDLE. That way you limit any movement to actual movement of the spindle in the headstock.

              if you get the same type results, then we'll talk about more things.....

              if your spindle bearing has ever been replaced, and I would almost bet that it has, then you could have a problem, but not 8thou, or even 5 thou worth of problem. My guess is that you are measuring the sum of other issues common to older machinery, and which are fixable if found.

              Stuff that can cause that movement between tool and spindle includes the following:

              headstock not tight down on bed. possibly resting on a piece of swarf and able to tilt.

              Sloppy adjustment of gibs in crosslide and/or compound

              Just plain wear. Wear in some places and in a certain manner, can let parts "rock" and cause issues. So can a piece of swarf under the compound swivel

              A toolpost that is too flexible. The "lantern" post can do that, especially if the tool and/or holder is stuck out too far.

              Sticking the compound and/or cutting tool too far out. Keep the front of the compound over the dovetail way it moves on.

              Having the work sticking too far out

              Not having the chuck screwed down to seat properly on the spindle, which can let it move.

              This is a partial list, there are more things..... And, there is always a little bit of flex in the lathe itself. Might amount to a thou or so with a heavy force. But the Logan is a very nice usable lathe of its size, I have a model 200, which is very much like your machine, just an earlier model, and I like it. There is no way stuff should move to the degree you suggest.
              Last edited by J Tiers; 02-07-2019, 08:17 PM.
              1601

              Keep eye on ball.
              Hashim Khan

              Comment


              • #8
                RockingJ, perhaps to quiet the doubters you might describe the setup used to test for the play you found? I just assumed that you would be securing the dial gauges to the bed and lifting, pushing or pulling to get those readings.
                Chilliwack BC, Canada

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                • #9
                  Looking back to the original post, He did say he had it apart to clean and lube the bearings. I'll becha a beer a readjustment to the bearings will fix this. If it's that far out, it's probably been that way since he put it together after the lube job.
                  I cut it off twice; it's still too short
                  Oregon, USA

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                  • #10
                    Originally posted by BCRider View Post
                    RockingJ, perhaps to quiet the doubters you might describe the setup used to test for the play you found? I just assumed that you would be securing the dial gauges to the bed and lifting, pushing or pulling to get those readings.
                    I set up a dial indicator on the top of the chuck and the mag base was on the top of the gear cover. First I put a lever under the chuck and lifted the chuck with out a lot of pressure just enough to see if there was play. This method showed me .005”. Then I set up with a carbide insert parting tool in my quick change tool post with the least stick out I can get with that tool holder. I still had the indicator set up on the top of the chuck. I ran the lathe at the slowest speed back gear and as soon as I put normal tool pressure on the part the chuck rose up .008. This rules out cross feed problems, compound problems.

                    The parting blade was exactly on center. I have 4 different chucks and I have this issue with all of them.

                    I haven’t checked if I get the same issue on the just the spindle, I will do that tomorrow.

                    I know my lathe is old and has issues but nothing major. I am fairly competent as a machinist and have been running this lathe for about 10 yrs in a hobby shop setting. I used it in my fabrication shop occasionally but not often. This parting issue is not a new issue, I’ve always had the problem but I’m finally getting around to addressing it.

                    Comment


                    • #11
                      When it comes to lathe age, mine is coming up on 79. I replaced the original spindle bearing, which I still have, because there was uncleanable old grease in it that made it "bumpy" as it turned.. And on that replacement hangs a story, one not entirely to Logan's credit. But we can save that until the measurement has been further explained.

                      We really need to know where the base of the indicator holder was, and what the tip was on, before the 5 (or 8) thou can be evaluated properly.

                      Eh, that's what I get for dealing with supper before finishing the post.... OP posted before I hit the "save" button.
                      Last edited by J Tiers; 02-07-2019, 11:44 PM.
                      1601

                      Keep eye on ball.
                      Hashim Khan

                      Comment


                      • #12
                        Originally posted by J Tiers View Post
                        We really need to know where the base of the indicator holder was, and what the tip was on, before the 5 (or 8) thou can be evaluated properly.
                        The base was on the gearbox cover and the indicator tip was on the chuck body. This eliminates anything to do with the carriage, cross-slide etc. (post #10)

                        Comment


                        • #13
                          Originally posted by J Tiers View Post
                          When it comes to lathe age, mine is coming up on 79. I replaced the original spindle bearing, which I still have, because there was uncleanable old grease in it that made it "bumpy" as it turned.. And on that replacement hangs a story, one not entirely to Logan's credit. But we can save that until the measurement has been further explained.

                          We really need to know where the base of the indicator holder was, and what the tip was on, before the 5 (or 8) thou can be evaluated properly.

                          Eh, that's what I get for dealing with supper before finishing the post.... OP posted before I hit the "save" button.
                          when I got my logan it had a rough growling noise when running. The previous owner told me to let it run until the grease got soft and it quieted up. it never did, so I replaced the bearings with new ones from logan. runs good now.

                          Comment


                          • #14
                            Some posters seem to think they know everything !

                            Originally posted by nickel-city-fab View Post
                            The base was on the gearbox cover and the indicator tip was on the chuck body. This eliminates anything to do with the carriage, cross-slide etc. (post #10)
                            I have been running lathes and other machine shop tools for 55 years. In that time I have had quite a lot of experiences, most good, some bad, and nearly all interesting.
                            One thing I have learned is that , very often, the man who says the most, really knows the least.
                            To say that a lathe cannot have eight thous lift on the mandrel is NONSENSE ! I have used and repaired old junkers with that and more.
                            I have met bearings loose in housings and bearings put in wrongly , not preloaded and some simply worn out.
                            One big heavy old bundle with plain bearings I ran had about 50 thous play, the owner tightened that up by using an angle grinder on the caps.
                            Best wishes to all those wanting to learn, lets give them real help not Nonsense, pretending to be facts.
                            Regards David Powell.

                            Comment


                            • #15
                              Let me update a bit.

                              I rechecked everything tonight. I set up the mag base on the side of the head stock, to remove any chance of the problem being from a movement of the gear cover. With the indicator tip on the top of the chuck backing plate. When I put a lever under the chuck I got .004” of lift. Then I took the chuck off and measured the lift doing the same lever under the spindle, I got .003 of lift. I then put the chuck back on and using a carbide insert in a holder on my axa quick change tool post of only the finest chineesium, when I tried to part off some hot rolled steel, I measured .004 of rise and then the part grabbed and broke the insert. If I raise the tool holder any at all ,all it will do is rub. I have verified the tool is right on dead center.

                              So my memory stretched the original measurements, hey I’m old, I can get away with it most of the time!

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