Grinding removable Leblond lathe ways - Page 2
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  1. #21
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    No the front one is tilted. Why?

  2. #22
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    I haven't run all the checks yet but I know there is .0025 wear on the front way and on this lathe the compound is very tall so that will tilt it twards and away from the work and cause around .005" variance in diameter. Do I really need to do it? Probably not but it is only $200 to have them ground and make them perfect.

  3. #23
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    We have taken the ways off of Warner & Swasey slantbed NC's and reground them but they have a pretty large cross section and they set on a aligning key on the bed. Those ways were originally ground on the bed and when removed usually had a bow in them. As someone previously said the case hardening is not very thick and it is not uniformly hard down to where it is soft. Bed ways we reground didn't last as long the second time being softer after grinding. We also ground through the case hardening at least once and got to the point where the last of the hardened layer would peel off like tin foil. We always made up the lost material by glueing a plastic way material to the bottom of the saddle.
    When I worked at American Tool Works in Cincinnati their NC lathe hard ways were ground off the bed. The surface on the bed where they sat was scraped flat to align the ways using an autocolimator and mirror on top ofg the way for measurement. After it was flat in one plane a guiding edge had to be scraped straight and the way was pulled against the edge with cams before being bolted down. People who did this everyday took about a week per bed to install a set of ways. This may be one reason they are no longer in business.
    LeBlond ways are probably fatter than American's but skinnier than W/S. Fixing your ways right is probably beyond the average machinist's capability not because of skill required but because of an inability to measure as close as required. Of course if it is so bad you can't use it go for it.

  4. #24
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    I'm gonna tell ya. I've rebuilt and aligned machines for 26 years and It ain't no picnic. Just what are you going to do with this lathe and wouldn't it be fun if you couldn't remove and clean the surfaces and just for the fun of it slide a few shims here and there and see what happens. Mind you my expertise was Swiss jig borers, Boring mills etc, but this is not to say I was not good at extracting the very last bit of life from existing slides. A lathe is a lathe. My Cincinnati fell .017 as it approached the chuck. I did regrind my ways. The bed was cast in 1954. It was time.

  5. #25
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    At Lodge and Shipley we ground the ways on a big Mattison strip grinder in sets then torqued them to the bed. When I shot the laser during final machine runoff you could see where the cap screws were but it was less than .0005 deviation. If there was a high spot the assemblers just pulled out the breaker bar and pipe and pulled them down more. These were on the CNC machines. These were supposed to be replaceable but not regrindable.

    Dana

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    My point exactly. Probably after one of these Large and Shapley's ran for a few years you would see a ghost of where every screw was and where every screw was not.

  7. #27
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    If your front way is tilted and you grind the exact amount from both bars the front way will fall a greater amount than the flat way. This will necessitate excessive scraping. If one way is f;at and one way is angular the angular way throws a wrench into the works. Not to awfully serious but you must pay attention to it. It must be calculated by someone who understands Geometry or you will be in for some rude surprises.

  8. #28
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    LeBlond Quality ?
    I had a 1944 LeBlond 15 inch Lathe that I rebuilt, from ground up. The ways were solid at that time, and quite beat from years of hard work.
    My Employer bought a brand new 5 inch 5 axis boring mill (80,000+ pounds) for a third of a million bucks.
    As the supervisor, I trained my machinists on programing it AND gave it a trial run to check out its capability, which was to .0001 tolerances.
    Included here was rebuilding "my" Leblond, as I wanted to reface the ways and it became the trial balloon.
    So up went the bed on two 60 inch tall angle plates.
    Now at the rear of the bed, below the way, was a 4 foot long BOSS, about 5 inches tall and having a 2 inch wide keyway, with 1/2" tapped holes every 4 inches. It looks like some sort of taper attachment mounting device, but one I have never seen anyware else..even to this day.
    I had called Leblond years earlier and spoke to an "old" engineer and he could not confirm the use of such a 'special" boss. Only that it was "War Time"
    Since the tailstock had a stop, 2 inches short of the end of the ways, and the ways under the headstock were perfect, my machinist set up the lathe bed to these points, before refacing the ways.
    Now here is the punch line.. I told him to indicate the "Boss" ..just as a second reference.
    he called me over to say "the indicator is shot, it doesn't move"
    Turns out the original ways and the boss are dead nuts.
    Closer examination of the boss, shows scrapping marks. I could not find more than .0002 difference anyware
    I would say that those boys really knew their stuff , even if it was during the war!

    The new ways were now perfect. I trigged out the difference in removal between the rear ways and the front due to the angle

  9. #29
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    Most of your major machine tool manufacturers in the '40s '50s '60s had planers that were their absolute pride. Set up with wire gages and .0025"/ft levels were so frightfully acurate that the average machinist would think you were exaggerating if you would describe their capabilities. When a bed was planed they would cut all long travel surfaces on a single setup. Whenever trying to regain original alignments you can usually find some unused liner edge. I have witnessed this accuracy of the past many times. It only makes me want to take my hat off to those before me who did so much with so little.

  10. #30
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    I'm planning to buy a LeBlond 15" or 19" to restore and use in my home hobby. So far, I've located 6~8 candidate LeBlonds, but none are pristine.

    So, about 10 days ago, I called two way grinding firms [American Machine Rebuilding in NJ and Gallery Of Machines of NY] to get their advice and prices for re-grinding the ways on LeBlonds.

    [1] Both firms strongly advised against grinding the ways apart from the parent bed. They presented several reasons that grinding the ways separately may be unproductive [e.g., the parent bed could be warped from years of improper leveling].

    [2] Both firms emphasized that grinding the ways is only a part of the overall accuracy equation -- proper accurizing of the saddle and other components is essential after the ways are ground. One of the firms indicated that the other work [such as presented above by Forrest Addy] would actually cost more than grinding the ways.

  11. #31
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    Just so no one says it again here: I know that regrinding the ways isn't rebuilding the machine! Now no one needs to say it again on this thread.

    traytopjohnny: If I were to moglace the carrage down on the reground ways would't that solve the very small missalignment that could happen on the rear flat way?

  12. #32
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    No! No! N01 No!. Moglace or Moglice or how ever it is spelled is snake oil. It is a temporary fix to give you a warm and fuzzy feeling for a fleeting moment till oil creeps in between the iron and the miracle cure. Now what do you have? You will have to correct your ways in whatever manner you choose and then your going to need to remove iron from the mating surface under your saddle. Scraping! There's not much getting around it. If you want to do the job annd have it done right. I will say one thing, I recently looked at a friend of mine's Regal and the underside of the saddle looked difficult to scrape. Just getting in and touching the iron with the tip of the scraper in a comfortable manner looked like it was going to take some proping up and then you would have to change dirrections of cut to reach down into each corner. I'm headed to the Flea market.

  13. #33
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    I've been following Johnny's remarks with interest and boy do we agree on Moglice.

    In a few rare cases Moglice can save the farm but mostly it's - well, snake oil; stuff that a bean counter mentality would clutching at like straws when an expensive rebuild looms. Moglice in a half nut? What a cruel joke. After a dozen closures there's moglice chips stuck in the thread spaces and raining into the chip pan.

    I've seen a couple dozen moglice repairs and rebuilds. All I can say about moglice is (if done right) you do save a little by avoiding relocating lead screws and power shafts. OTH moving end brackets and feed transmissions around is no big deal. Prepping for Moglice, setting up the saddle (whatever) on parallels in accurate alignment, damming off the escape paths, gunning in the Moglice, etc, is a huge fussy PITA and it very rarely pays.

    On the other hand you better have the best way wipers and operator hygene money can buy because NOTHING makes a better lap out of mill scale, rust, tramp abrasive, and chips than Moglice.

    Turcite? That's a different matter. This is touchy but effective stuff. While you have to go through many of the same prep and bonding steps as with Moglice you can - if you work carefully - restore the sliding elements to their original heights and alignments saving relocating the end brackets and feed transmissions. You still have to be almost hysterical with the efficacy of the way wipers. I don't think I'd ever reccommend Turcite against anything but hard steel ways and cast iron only in a pinch.

    If someone held a gun to my head and asked me who played the most vital role in a plain way machine tool rebuild I'd point to the planer hand not the man on the scraper. A good planer hand can save a mountain of scraper time and take a lot of the pain out of securing the final alignments. He has the machine and the dial indicator right there and if properly leveled his planer will cut planes and their intersections as straight and level in 20 minutes as the best scraper hand in a full work day.

    Ask me about bonded cast iron way liners and IronTite repair screws.

  14. #34
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    So with all this info what is the best plan of attack at rebuilding a leblond, as i have a 19" that is going to need rework it's an nc that i'm going to convert to cnc. This is for my home shop it will never see full prodution. Todd

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    Traytopjohnny and I have been good friends for close to 20 years. I have seen his excellent rebuild work on jig bores, boring mills and planers at Cincinnati Milacron, that ran heavy production for years. He is very meticulous, almost religious, about accuracy in alignments, etc. And rightly so, his concept of failure is a .0002" error inside the 36" machining cube of a Csip jig borer! He does absolutely amazing work!

    I am the friend who is rebuilding the 15" LeBlond lathe, and with apologies to Forrest, I pulled and reground the ways knowing that a complete rescrape would be necessary. TTJ is helping out here, he is the Zen master to my grasshopper. I have to remind him on occasion that it's a lathe, not the space shuttle! To quote the Chief Engineer at RK LeBlond: "It's only a goddamn Regal!" I'll let you know how things work out over the next few months!

    I was aware of the alignment issues with the leadscrew and properly trigged the grinding stock removal so that the half nut centerline would only drop in the vertical plane.

    I worked at RK LeBlond before it became LeBlond Makino, so I can offer some recollections. The Regal lathe line was redesigned in '53-'54 to the familiar modern style with squared off castings, legs. etc. I believe this was about the time that the hardened, replaceable ways appeared on all the various LeBlond lathe models. The replaceable ways were 6150 steel (as I recall) and were induction hardened & quenched on three sides. This left the underside soft so that the mounting holes could be drilled & tapped. The "hard bars or shear bars" as we called them, were straightened, surface ground all over, then mounted to the planed beds. The surface hardness was 62-64Rc, but since the material was through hardening, a wide transition zone occured. (This is why I am not concerned about the regrind on my 15" Regal ways. If the new reground surface is only 55Rc or 50Rc, its still harder than the cast iron carriage. I'll never wear things out! If I can locate a Shore hardness tester, I'll verify the final hardness.)

    I can only recall the rare occasion when a lathe bed with the ways installed would be surface ground. These would be the NC lathes like a Tape Turn IV or Tape Turn 1212, which had a pair of rectangular box ways, not any lathes which had the angular mount front way. The Heavy Duty and Wide Bed lathes beds were all planed, then had the ground ways bolted on. The Wide Bed lathes had bed sections that came in 40' length increments (as I recall, perhaps less). If a long center distance lathe was ordered, multiple bed sections would be attached end to end. Those ways were all surface ground, the ends ground square, then bolted to the bed sections, and they butted seamlessly end to end.

    About '82 or '83, LeBlond acquired a large Waldreich Coburn grinder, which had angular wheelheads. The Regal lathe manufacturing had already been transferred to Singapore, and the Baron 25, 40 & 60 series CNC slant bed lathes, introduced in 1980, were well into production. They may have surface ground the ways in place on those beds at that time.

    Mike

  16. #36
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    OK Forest - no Moglace. Would you or anyone please help with the math needed to grind the correct amount off the rear way so the saddle remains paralell to the ways.

    The front way is tilted twards the operator at 20 deg. from level. Let say I need to grind off .004 from the top and the side of the front way to clean it up. How much lower will the carrage ride? The amount lower will be the amount to grind from the rear way to keep them in alingnment right?

  17. #37
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    I'm back from the flea market. Forest Addy sounds as though he has been in the trenches as well. Sounds as though he has witnessed would be rebuilders seeing wear and the mind set comes in that all I need to do is remove the roughness that is visible and all will be well. It is not like that. If you carefully calculate how much to remove from each way and you bolt them back on and all does not go well, take one or the other off and have one, two maybe three thousandths more taken off one or the other. Unless you want to plow some iron, careful planning is the whip. Become familiar with the quality of work the guideway grinder or planer you are about to have do your work is capable of. If you drive your truck to a building and drop off a piece of iron you are concerned with, and you arrive back in a day or two, pick it up and get home with it, you have what you have. The metal is gone. If there is a problem, at best, If you are lucky, they can take more metal off. Chances are, if the first pass was no good the second pass will be no better. Know your provider.

  18. #38
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    If you wish to accept a scraping job you had better have a fist full of scrapers and a quality diamond wet face wheel to sharpen them on. The inexperienced will tend to round the cutting face and cause to narrow a cut. A properly sharpened scraper will be able to shave a finger nail when lightly brushed with the edge. When you have a scraping job to do you have iron to be removed. In order to get this accomplished you must push and cut hard. If you are unsure of what you want and are stalling for time you had better sit back and make sure of what you want. If there is more iron in one area than you want to be there and you are sure of it, Cut it out of the way. Get rid of it. People I knew when I was in the trade who i respected had smoke comming from the tip. If you do not believe me, well I guess you just do not believe me. That is all I will say on the subject.

  19. #39
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    This is a great thread. I've often wondered how they originally made lathes and other machines with replacable ways.

    Reworking my Leblond will be strongly influenced/controlled by 2 factors: [1] the lathe will be used for occasional home hobby use, not long term, high-precision production, and [2] money is much more scarce than time.

    Thus, this basic approach: [1] get a competent shop to grind the ways off the bed; [2] shim the ways back up to their original position (approximately) by using 'circular shims' that surround each hold-down bolt; [3] fill the gap between the ways and the bed with a homemade composite of epoxy & Kevlar; ... and

    [n] make a complete photo and verbal record of this process and attach this record to the lathe so that when I'm dead and gone, any prospective buyer can readily see what was done to this particular lathe.

  20. #40
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    I'm glad Johnny and Mike have joined us to reinforce the "do it right" blast.

    It's true one can get carried away with accuracy and refinements but the recent "way lapping" thread and others I've seen reek of false promise. For that reason I'm quick to scotch simplistic methods sketched in glowing terms because their many traps and poor assumptions delude the unwary and may result in the ruin of their beloved machine tools.


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