Bought my first lathe - tell me how bad I did - Page 2
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  1. #21
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    And take note of what I said about oil level in the head....if the rear bearing isnt oiled it will seize......Ive seen lots of ruined spindles in these machines.....but ruined by pressing off the bearing after it has seized....so if the bearing is seized ,ask advice,dont try to press it off.

  2. #22
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    Quote Originally Posted by john.k View Post
    And take note of what I said about oil level in the head....if the rear bearing isnt oiled it will seize......Ive seen lots of ruined spindles in these machines.....but ruined by pressing off the bearing after it has seized....so if the bearing is seized ,ask advice,dont try to press it off.
    Thanks for the heads up on that. How exactly should the bearing be replaced if pressing it off isn't the right way? If there's one thing it seems the previous owner did well, it was keep it oiled. The constant stream(s) of oil coming out of it probably kept it fresh in his mind. So far it seems like one of the primary leaks is coming from the spindle seal, which I would assume isn't too difficult to remedy.

    When I first looked at this machine, I had chalked it up as too far gone and most likely a parts lathe. I will say this lathe has (so far) had it's share of scary moments. Particularly because I have nearly zero experience with lathes. Last night I was spinning the drive pulley with a drill to check function on everything and I noticed my lead screw was not turning, and I couldn't get it engaged with the lever. I pulled open the gearbox and discovered the shifting lever paw had somehow spun past (and out of) it's race, so that was yet another easy fix. All of the gears looked pretty good. Once I get the new motor and VFD installed and verify functionality, i'll be tearing it down for a rebuild. Maybe not entirely down to every part, but I need to verify all the gears and shafts are good and tight in their bearings. Afterwhich, I expect I'll know this machine inside and out.

  3. #23
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    You should cut the race off with a grinder.Carefully.....The damage is done in pushing off when the whole spindle is scored and grooved.Anyhoo,hopefully ,your s hasnt run with low oil .Oil leaks from the thread/feed gearbox cant really be helped,best to use the thickest oil you can find.....I use steam cylinder oil....These machines also have problems with the leadscrew drive ,and I suspect yours has been disconnected on purpose.......Never ,never ,try to cut coarse LH threads ....gears will break for sure.......I would advise against removing parts in the head ,unless there are obvious problems.....and removing the head casting from the bed will leave you with a realignment chore.....If you have good gears ,then the machine hasnt done a lot of work......Parts ,even used,cost a fortune.....However ,do pull the apron to pieces and clean out all swarf and rust...and my advice,never use a bed stop /feed kickout ...something will break sooner or later...sooner ,actually.

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    Quote Originally Posted by john.k View Post
    You should cut the race off with a grinder.Carefully.....The damage is done in pushing off when the whole spindle is scored and grooved.Anyhoo,hopefully ,your s hasnt run with low oil .Oil leaks from the thread/feed gearbox cant really be helped,best to use the thickest oil you can find.....I use steam cylinder oil....These machines also have problems with the leadscrew drive ,and I suspect yours has been disconnected on purpose.......Never ,never ,try to cut coarse LH threads ....gears will break for sure.......I would advise against removing parts in the head ,unless there are obvious problems.....and removing the head casting from the bed will leave you with a realignment chore.....If you have good gears ,then the machine hasnt done a lot of work......Parts ,even used,cost a fortune.....However ,do pull the apron to pieces and clean out all swarf and rust...and my advice,never use a bed stop /feed kickout ...something will break sooner or later...sooner ,actually.
    Did a full inspection of the gearbox this evening and saw no damage to any gears, looks good throughout. I have yet to inspect the headstock gears but they all work and I don't hear any issues. As for the leaks I intend to make new gaskets on all the major surfaces to help remedy it. Should be easy.

    So, why do coarse left hand threads cause issues on these lathes? I was planning on cutting most all of my threads in reverse with the threading tool flipped so I can cut away from the stop instead of towards it.

  5. #25
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    The leadscrew thrust bearing surface is virtually unlubricated inside the box for RH threads and isnt outside the box for LH threads.....Its a very poor setup,and I suggest before cutting a thread ,engage the half nut and turn the gear train by the chuck to test for bind........you may find with LH threads the whole thing just jams up............The obvious cure was applied in the Bantam,by putting a proper greased thrust at the tailstock end of the leadscrew......I would try to fit roller thrust washers ,but I dont do any threading on the Master,so I havent bothered.

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    As I recall matters its a labyrinth seal on the spindle. Basically grooves and close fit pull the oil back. Effective when new or not too old. Usual reason for leaks is build up of crud in the drain and grooves over umpty four years so it eventually stops working. Spindle out job to clean and fix so most folk live with the oil loss.

    Do remember that these machines were built to a price and to be destroyed for the value of the work they produced. Design life for sensible RIO on the factory floor was probably a decade or maybe two. The important fundamentals are good and solid but there are some short cuts and cheapening involved. Mostly in the apron I think. New price was extremely good. You got a lot of specification and performance for your money.

    Despite the less than ideal lubrication arrangements for the leadscrew thrust bearings these lathes typically manage many years of work before wear becomes an issue. If its worrysome I'd look into installing a dry lube faced thrust washer or, better, face to face pair to take the load which will do fine under minimal lubrication. Been a very successful "go-to" technique for me over many years and a fair few applications, although not a leadscrew thrust.

    Clive

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    The Master I have now came free ,it having been dismantled and every bearing surface hardchromed.....and never reassembled due to death of owner.....fast forward 20 years ,another owner passes without doing anything to it,and a Weiler Condor similarly in pieces.....sadly the scrapman got the Weiler bed before wiser heads had a chance to look.......the guy also had four ,yes four,Manx Nortons and a couple of con artists got them for a couple of bucks by harassing the widow at the funeral...talk about lowlifes,and I do know who they are.

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    Quote Originally Posted by Clive603 View Post
    As I recall matters its a labyrinth seal on the spindle. Basically grooves and close fit pull the oil back. Effective when new or not too old. Usual reason for leaks is build up of crud in the drain and grooves over umpty four years so it eventually stops working. Spindle out job to clean and fix so most folk live with the oil loss.

    Do remember that these machines were built to a price and to be destroyed for the value of the work they produced. Design life for sensible RIO on the factory floor was probably a decade or maybe two. The important fundamentals are good and solid but there are some short cuts and cheapening involved. Mostly in the apron I think. New price was extremely good. You got a lot of specification and performance for your money.

    Despite the less than ideal lubrication arrangements for the leadscrew thrust bearings these lathes typically manage many years of work before wear becomes an issue. If its worrysome I'd look into installing a dry lube faced thrust washer or, better, face to face pair to take the load which will do fine under minimal lubrication. Been a very successful "go-to" technique for me over many years and a fair few applications, although not a leadscrew thrust.

    Clive
    Okay. A little confused but let me make sure I understand. On the tailstock side of the leadscrew you add a thrust washer bearing? I'm assuming since the concern is LH threads you're saying it should be added to the left side of the boss? How do you secure it, machine a shoulder or use a collar with a set screw? I believe there is some sort of a collar there now. Seems like an easy insurance policy given your experience.

  9. #29
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    Nope.....the only place for a thrust is where it is now.....What I was suggesting can be plainly seen if you have a look at the setup on your Bantam....However this will require a reworking of the simple bushing thats there now.....As I said ,if the Master was my only lathe ,then I would have a look at this.......buuut....before I went to all this trouble,I would make sure the leadscrew and halfnut were serviceable......which mine are not.

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    Pyrex

    Apologies for confusion. My fault I should have dug out a manual rather than relying on memory as to how the thrusts were handled. Was thinking of wrong breed of machine.

    Don't have a Master manual to hand but I'm pretty surer yours has the same gearbox as the Student, which I do have aPDF manual for.

    Looking at the parts section its clear that the leadscrew is retained at the gearbox end with arrangements to take thrust both ways at that end. The tailstock end bushes are plain so the leadscrew floats at that end.

    Essentially the leadscrew sits inside a hollow T shaped bush which actually runs in the garbox bearing. The top end of the T carries thrust pulling the screw assembly to the left. Thrusts to the right are taken via a thrust collar sitting on the T shaped bush. The righ end of the collar is threaded to accept the two nuts used to set and lock free play. I think you need bot machine and parts book in front of you to make sense of how it all goes.

    The thrust surfaces are supposed to be lubricated by oil working out of the bearing bush. I seriously doubt that the full oiling schedule was adhered to on any lathe significantly past the first excitement of installation.

    Clive.

  11. #31
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    The leadscrew drive /extension is the top shaft in the gearbox,and the possibility of splash is remote.....I found greasing with pure molydag is best,oiling from the top ,not so good.......there seems to be massive friction in the setup,even when well lubed......hence my warning to work your threading setup by manually turning the chuck as a check on loading,and be sure to flood lubricate saddle ways,and the leadscrew.....A simple project would be to install a grease passage to the thrust setup from the front of the box.,then use moly.


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