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  1. #61
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    Quote Originally Posted by simonl View Post
    Hi Mike, thanks for your input.

    In my case i would disagree on the S/H worn out lathe being a better option to a new Chinese. My Chinese lathe is far more capable of accurate work to a worn out well built lathe of yesteryear. Sure, I can attempt to buy an old one and re-furbish it. I may even succeed but at the time I aquired my Chinese lathe, I had no lathe work experience. How would someone who is just starting out and wanting to learn turning be in any position to (1) know what they are looking at and (2) identify and know how to fix the issues?

    Simon
    They can't.

    Second question though - how can someone just starting out know the difference between a totally crap brand new lathe and their lack of skill/ability in machining?

    They can't.

    I've said it before and I'll say it again. Using H&F as an exemplar of the better end importers, IMO (and at least one of their sales people) there is no lathe that they sell less than the AL960B that can be *relied upon* to be good - as in meeting recognised standards - straight out of the crate. You can get lucky, and the next machine can be crap.

    This isn't a cheap hobby if you want to work consistently to fine tolerances. It costs money for the equipment, it costs money for the measuring gear and it costs a *lot* of time to learn what you're doing. If you have the time to learn the skills, you can buy machinery that isn't up to specification and rebuild it to the standard you demand. Otherwise, you pay in hard cash.

    As for torque shimming, I agree with Bob - this is a kludge to substitute for proper manufacturing. It saves money at assembly time and has nothing else going for it. Anyone with the time & patience would, if the machine has been disassembled already, be well served in blueing the HS to the bed just to see what the bearing around the bolts was like. Knowing this, at least you're in a position to make a judgement on how to proceed.

    IIRC RC had a very comprehensive thread on realigning the 10EE HS posted on PM in the Monarch sub-forum. Anyone thinking of having a crack at realigning their HS would be well advised to read it.

    PDW

  2. #62
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    Oh, and BTW Simon - if your Chinese lathe was capable of better work out of the box than an older industrial one, just why did you strip down the HS and replace the bearings?

    I'm not picking on you - just that the fact you decided you had to do this demonstrates that your machine wasn't capable of accurate work, as delivered.

    The bearings in my 1942 Monarch CY lathe are still in perfect condition. As are the Gamet bearings in my 50 year old Chipmaster.

    PDW

  3. #63
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    Quote Originally Posted by morrisman View Post
    I had read about the precision bed to the base fitting the Harrison factory had done, and the advice is, under no circumstance, disturb the bed to base setup.
    This is where half this hysteria starts. And Electrical blokes like Chris, grab it by the balls, and go to town with it.

    Wouldn't the matter of fact be that your Harrison head stock resides on a Vee way and a flat. And that Vee way is an extension of the Vee way that the saddle uses? In fact its ground at the same time as the bed. What they should have said was "Our Scraper hands are world class, don't attempt to better that".

    Am I wasting my time? Your on about "bed to base' Pretty sure we're talking head stock / spindle axis to bed here.

    So its not so much a case of "Under no circumstances, disturb the bed to base setup". Its rather a case of you "Couldn't disturb that set up if you tried", short of shimming, torque shimming(T.M"), angle grinder, or indeed taking to it with a scraper. Shovelling in off cuts of old Coke cans /paper / Eye of newt, tobacco paper, BASF 8 track tape, doesn't count.

    The fit of that head stock, whilst bruise free/ stoned / gospel clean will repeat with in a tenth, if you took it off and on a dozen times. Its the very nature of a positive location devise such as a dovetail location. The rest of the machine wouldn't be constructed out of them if it wasn't such a perfect system.

    None of which matters in Simon's example. His sits on two flats. Totally adjustable . (I'd note he has lifted it before, and found no shims / Eye of Newt). None of which is any harder than dialling in a tail;stock, setting the top slide at zero.

    Just make it cut parallel, no test bar required. I can loan him one. I never use them. A dynamic test is the only test that a customer will sign off on.

    Phil.

  4. #64
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    Quote Originally Posted by PDW View Post
    Oh, and BTW Simon - if your Chinese lathe was capable of better work out of the box than an older industrial one, just why did you strip down the HS and replace the bearings?

    I'm not picking on you - just that the fact you decided you had to do this demonstrates that your machine wasn't capable of accurate work, as delivered.

    The bearings in my 1942 Monarch CY lathe are still in perfect condition. As are the Gamet bearings in my 50 year old Chipmaster.

    PDW
    Hi PDW, I never mentioned it was capable straight out of the box. It suffered from the same issues that other Chinese lathes have, sand, rubbish and other impurities in the HS which over a short period of time destroyed the spindle bearings. This rendered it incapable of a good finish. But, it was still easier to fix than a worn out lathe and while I did make some mistakes with it's repair and re-assembly, I still managed to do it. There is no way I could have fixed a lathe with a worn out bed.

    I'm very happy with it now. If I have bought a S/H worn out lathe, chances are it would still be worn out and probably rusting from lack of use and frustration.

    No need to worry about picking on me, I have broard shoulders!

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  5. #65
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    Quote Originally Posted by Michael G View Post
    I chose that one because it used a test bar.
    You did read the part about reading and averaging the run out of the spindle, and using the mean position of run out to do geometry? Its allowed to revolve the bar, so you get the mean avg near the spindle nose, and again at 300mm out.

    This covers one of Simon's questions about the precision of the bar. He mentions an accuracy of 10um. Slam a test bar in and it 0.04mm T.I.R/300 out. Unless you have a certified bar and you can add or subtract the error of the test bar. In the orientation it is in. How much do you know is in the bar, and how much is in the interface? That could be 30 or 50, depending on how you insert the bar.

    Phil

  6. #66
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    Quote Originally Posted by bob ward View Post
    Thinking about this a little further, the class of lathe makers who *“torque shim” their headstocks into alignment wouldn't just be machining everything close enough as I say above, lathe bed and.
    How do you figure they machine all those head stocks, so they rock? Perhaps they buy all the flogged out Bridgeports from Practical Machinist?

    Any machine I've ever seen to tries to cut true, flat, parallel and square. What sort of machine do you in-vision the Chinese are buying, that cuts on the Piste, that it cuts a rocking chair?

    Perhaps Criss can help here

    I'm aware of one. Ascherleben Slide Grinders. They are famous for being able to put the crown on a Maho, Deckel, Huron. All ram machines. As it extends further out, it droops. So you cant scrap in line, you have to bias it. I dug 27 thou into my first one before I worked it out. Ascherleben's 2nd hand start at about 2Mil Euro.

    Tell me again how the Chinese are deliberately machining the " deliberately machining the lathe bed and underside of headstock to ensure that the HS rocks.

  7. #67
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    Quote Originally Posted by Machtool View Post
    This is where half this hysteria starts. And Electrical blokes like Chris, grab it by the balls, and go to town with it.

    Wouldn't the matter of fact be that your Harrison head stock resides on a Vee way and a flat. And that Vee way is an extension of the Vee way that the saddle uses? In fact its ground at the same time as the bed. What they should have said was "Our Scraper hands are world class, don't attempt to better that".

    Am I wasting my time? Your on about "bed to base' Pretty sure we're talking head stock / spindle axis to bed here.

    So its not so much a case of "Under no circumstances, disturb the bed to base setup". Its rather a case of you "Couldn't disturb that set up if you tried", short of shimming, torque shimming(T.M"), angle grinder, or indeed taking to it with a scraper. Shovelling in off cuts of old Coke cans /paper / Eye of newt, tobacco paper, BASF 8 track tape, doesn't count.

    The fit of that head stock, whilst bruise free/ stoned / gospel clean will repeat with in a tenth, if you took it off and on a dozen times. Its the very nature of a positive location devise such as a dovetail location. The rest of the machine wouldn't be constructed out of them if it wasn't such a perfect system.

    None of which matters in Simon's example. His sits on two flats. Totally adjustable . (I'd note he has lifted it before, and found no shims / Eye of Newt). None of which is any harder than dialling in a tail;stock, setting the top slide at zero.

    Just make it cut parallel, no test bar required. I can loan him one. I never use them. A dynamic test is the only test that a customer will sign off on.

    Phil.
    Wow . I am glad that I bought the Harrison after that glowing praise of it

    BTW when I wrote "half worn out lathe " this was misleading . I should have written
    " showing signs of previous use " which means a lathe which probably has many years of use left in it .

    Simon, the bed on my Harrison is hardened and it appears to be in excellent shape . It also has hardened and lapped gears in the headstock , the gears 'sing' a little at higher speeds but I think that's normal . Buying a new Asian lathe of similar dimensions and specifications, would have cost me twice or more, than what I paid for the Harrison

    I was in your position Simon . Absolutely nil knowledge of lathes or how to use them . I had not been near a lathe since cleaning one at high school in 1970 . I've taught myself mostly and forums like this are very helpful too.

    I did a TAFE entry level machining course , the lathes I used at TAFE were very large industrial things, not typical of what a hobby person would use and the teachers were time poor with a class of teenage kids to look after ( most of the kids didn't want to be there and they just wasted everyone's time , including mine) .I didn't learn much there to be honest . Mike

  8. #68
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    Quote Originally Posted by morrisman View Post
    Wow . I am glad that I bought the Harrison after that glowing praise of it

    BTW when I wrote "half worn out lathe " this was misleading . I should have written
    " showing signs of previous use " which means a lathe which probably has many years of use left in it .

    Simon, the bed on my Harrison is hardened and it appears to be in excellent shape . It also has hardened and lapped gears in the headstock , the gears 'sing' a little at higher speeds but I think that's normal . Buying a new Asian lathe of similar dimensions and specifications, would have cost me twice or more, than what I paid for the Harrison

    I was in your position Simon . Absolutely nil knowledge of lathes or how to use them . I had not been near a lathe since cleaning one at high school in 1970 . I've taught myself mostly and forums like this are very helpful too.

    I did a TAFE entry level machining course , the lathes I used at TAFE were very large industrial things, not typical of what a hobby person would use and the teachers were time poor with a class of teenage kids to look after ( most of the kids didn't want to be there and they just wasted everyone's time , including mine) .I didn't learn much there to be honest . Mike
    That's great news about the lathe Mike. Sounds like you did really well. Did you know when you bought it that it was that good or did you just get lucky?

    Simon
    Girl, I don't wanna know about your mild-mannered alter ego or anything like that." I mean, you tell me you're, uh, super-mega-ultra-lightning babe? That's all right with me. I'm good. I'm good.

  9. #69
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    Quote Originally Posted by morrisman View Post
    Wow . I am glad that I bought the Harrison after that glowing praise of it
    All this thread needs is the truth. Your read of the instructions was to die before attempting to adjust the headstock alignment. Much like Chris's Any chance you could post a Pic of that sitting up on a Vee Way

    Simon would be best placed here to show the interface between the headstock and base. That thing floats around like the Greek National debt

    But what ever you do. Don' touch it. The Super Ninga's, Head Stock alignment Chris Guru's wont have a second of that.

  10. #70
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    Quote Originally Posted by Machtool View Post
    How do you figure they machine all those head stocks, so they rock? Perhaps they buy all the flogged out Bridgeports from Practical Machinist?
    I think it more likely they machine fresh castings which then move. I can't see paddocks covered with thousands of castings waiting their turn some how, and stress relieving ovens are probably seen as an unnecessary luxury.

    Quote Originally Posted by Machtool View Post
    You did read the part about reading and averaging the run out of the spindle, and using the mean position of run out to do geometry? Its allowed to revolve the bar, so you get the mean avg near the spindle nose, and again at 300mm out.
    It's funny, but I do that so automatically these days that I did not think to mention it so it is a worth while reminder, but the selection and quoting of those figures was primarily to give the better figures for the standard accuracies as that particular bit of the truth had not appeared. While we could argue exactly which test should apply, I prefer specified numbers to uncertain memories of numbers. I also wanted to make the point that while Schlesinger standards are established, they typically do not encompass hobby type lathes so quoting compliance is more or less meaningless.

    Michael

  11. #71
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    Quote Originally Posted by Machtool View Post
    How do you figure they machine all those head stocks, so they rock? Perhaps they buy all the flogged out Bridgeports from Practical Machinist?

    Any machine I've ever seen to tries to cut true, flat, parallel and square. What sort of machine do you in-vision the Chinese are buying, that cuts on the Piste, that it cuts a rocking chair?

    Perhaps Criss can help here

    I'm aware of one. Ascherleben Slide Grinders. They are famous for being able to put the crown on a Maho, Deckel, Huron. All ram machines. As it extends further out, it droops. So you cant scrap in line, you have to bias it. I dug 27 thou into my first one before I worked it out. Ascherleben's 2nd hand start at about 2Mil Euro.

    Tell me again how the Chinese are deliberately machining the " deliberately machining the lathe bed and underside of headstock to ensure that the HS rocks.
    The ways of Chinese lathes are ground, not as fine a finish as on western lathes, but ground. That is where the Headtock sits on.

    The bottom of the headstock of chinese lathes is usually just roughly milled. By roughly I mean you can see about two cut marks per mm. The resulting "wavy" surfacre roughness seems to be enough to allow about +/- 0.05 of movement up down just by slightly tightening or loosening the front two hold down bolts of the headstock. That is what I call "torque shimming" in the absence of another word for it.

    Usually, the Headstock of Chinese bench lathes is not guided by the Vee's of the bed but free to float. But some lathes like the Sieg minilathe seem to use the bed Vees as a guide.

    Sometimes there is considerable grit (paint and castying sand) between bed and the bottom of the Headstock. This could be left there on purpose to increase "adjustment range".
    Sometimes, but rare, I have been told of paper shims being used. If used, all a paper shim would do is to increase the torque shimming adjustment range, by provindig a compressible interface.
    Sometimes file or rasp marks, or very very coarse scraping marks at one end only can be seen at the bottom of a headstock - that is how they "adjust" if Schlesinger's can't be met at the first attempt.

    I am assuming that the larger Chinese lathes (costing over 5K) would follow more serious practices. The smaller China made lathes below $3K definitely do not follow Connelly's book instructions - its just not possible for that sort of money. You can buy a Chinese 9" swing lathe at H&F for $1000. That is the whole lathe with chucks and rests and accesories and H&F's profit margin, for about 5 days of Australian average wages earnings. You would probably have to charge that much just for one days work if someone asked you to properly scrape that lathe into specs.

  12. #72
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    Quote Originally Posted by Machtool View Post
    Shovelling in off cuts of ..... BASF 8 track tape.
    Hmmm you've given me an idea Phil,
    I believe I might just have some rolls of that self lubricating magnetic shim strip you mentioned in a box somewhere.
    Perhaps I should try selling it by the metre on ebay as high precision machine tool shim stock.
    Gotta be worth a lot more than a box of flogged out old video cassettes.
    Cheers,
    Greg.

  13. #73
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    Quote Originally Posted by cba_melbourne View Post
    Sometimes there is considerable grit (paint and castying sand) between bed and the bottom of the Headstock. This could be left there on purpose to increase "adjustment range".
    Sometimes, but rare, I have been told of paper shims being used. If used, all a paper shim would do is to increase the torque shimming adjustment range, by provindig a compressible interface.
    Sometimes file or rasp marks, or very very coarse scraping marks at one end only can be seen at the bottom of a headstock - that is how they "adjust" if Schlesinger's can't be met at the first attempt.

    I am assuming that the larger Chinese lathes (costing over 5K) would follow more serious practices. The smaller China made lathes below $3K definitely do not follow Connelly's book instructions - its just not possible for that sort of money. You can buy a Chinese 9" swing lathe at H&F for $1000. That is the whole lathe with chucks and rests and accesories and H&F's profit margin, for about 5 days of Australian average wages earnings. You would probably have to charge that much just for one days work if someone asked you to properly scrape that lathe into specs.
    It's hard to know where to start with this.

    Suffice to say that, like Michael, I don't like to see the name's Schlesinger or Connelly used in vain, as neither have any relevance here. There are many people here on the forum who may not be familiar with either person. For the record a "Schlesinger" is not a thing or set of tests, it was a person who was reputed to be the first to develop a standard set of tests to quantify the accuracy of machine tools. Until then it was a bit of a mish-mash of tests that may not have been compatible between various manufacturers. This made comparison or acceptance of machines difficult, as there was no real standard to compare what was achieved with what should be desired. In the early 20th century Dr Georg Schlesinger published a book containing a series of tests for most common machine tools of the day which set down standards as to how they were to be tested and the desired results. They were not at the time compulsory tests, nor have they been since, however most machine tool manufacturers, certainly in this case of lathes, adopted at least some of the tests and publish the test results with the machine when sold. This is particularly the case with any quality tool. However because the tests are not compulsory, there is no guarantee that a test sheet provided contains the same tests as specified by Schlesinger, the tests were carried out to the same standards, nor that the results were to the limits set by Schlesinger's original specifications. This is particularly true with Asian sourced tools. They certainly may be, but shouldn't be assumed. For this reason the whole term adjusting to meet "Schlesingers" is a complete nonsense and makes no sense at all when viewed in regard the actual history behind this.

    In regard Connelly, I don't know how that could even come to be mentioned here. For those who are similarly scratching their heads, Connelly was a machine tool rebuilder who published a book on machine tool rebuilding, and in particular the use of scraping to align machine tool elements. I doubt any Asian manufacturers would have even heard of the gentleman, never mind follow his "instructions". The techniques he described were in any case applicable to rebuilding of worn machine tools and really had nothing to do with building new machines. The techniques described by Connelly are simply a book describing the techniques used by master craftsmen like Phil here, as they would go about rebuilding a worn machine. The text has a large introductory section on scraping followed by various machines and what are essentially step by step processes to start from a worn machine and gradually rebuild the machine components to finish with a functioning machine ready for final testing. Because a machine tool manufacturer is mass producing the machines, the whole process and methods used, particularly by large Asian manufacturers, are completely different to those described by Connelly, and again it's a complete nonsense for it to be referred to in regard new machines.

    Anyway, I have some fettling of some machines to do today, so I must remember to include some "castying sand" and paint to increase my adjustment range while "torque shimming" them in to Schlesingers.

  14. #74
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    Quote Originally Posted by Machtool View Post
    I'm aware of one. Ascherleben Slide Grinders. They are famous for being able to put the crown on a Maho, Deckel, Huron. All ram machines. As it extends further out, it droops. So you cant scrap in line, you have to bias it. I dug 27 thou into my first one before I worked it out.
    Phil, can you give a little more detail on this? I will be scraping my Deckel at some point. Incidentally it has the long reach ram. I wasn't aware that there's a crown on I assume the ram ways?

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    Quote Originally Posted by Pete F View Post
    In the early 20th century Dr Georg Schlesinger published a book
    A lucky few own a paper copy.. I had a second Schlesinger original on the way (to gift it) when Pitney Bowes managed to vaporize it!

    I digress.. For those interested it's available to download online ("Testing Machine Tools" is the title).

    Quote Originally Posted by Pete F View Post
    Connelly was a machine tool rebuilder who published a book on machine tool rebuilding
    This book is still available for purchase new - shipping internationally at a reasonable rate. A great well illustrated text even if one's not rebuilding machine tools.

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