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  • #46
    I think you're right, it keeps things within the realm what I know will work (lapping, grinding) vs what i'd be hoping will work (line boring the tailstock bore). The basic change in thinking for me is getting the tailstock barrel done first, then scrape to align it
    in Toronto Ontario - where are you?

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    • #47
      There was some discussion on the Monarch forum concerning the use of Turcite and Moglice on the tailstock bottom that ride on its ways. It seems that Turcite is not suitable due to its slipperiness. I find it alittle squishy as well, but that view is controversial. I decided to take a chance and use Moglice in this application, as the scraping alignment of the tailstock (yaw, pitch, roll) was more than my skill and patience could deal with. Using fixtures, which was more intuitive for my brain, I was able to dial in the alignment to original new Monarch specs. It has performed beautifully and has no tendency to slip when locked under load. Moglice needs to be flaked for optimum sliding performance, as it forms such a good mirror of its host surface. Knowing this can be beneficial in a virtually non-sliding component such as the tailstock. In other words, if you don't overly flake it, it will really clamp solid. Even on my heavily flaked carriage, I have found no tendency to slip using the lock. On another note, I made a new oversize tailstock quill. I had tried hard chroming the original, but found local services to be severely lacking, in doing high tolerance work. The hardest part is making sure the quill bore is round and true to very finicky tolerances. Then as said earlier, lapping the mating parts. And yes the quill/bore should be addressed, before any thought of tailstock alignment.
      Last edited by daryl bane; 09-07-2010, 11:03 AM.

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      • #48
        Well. I used Moglice on my TS (senior moment) and I wouldn't do it no more. I have to clamp it like mad, and still it slips (with a 30 mm drill ).
        It makes no difference wether you scrape Moglice or not. I didn't at the TS.

        Moglice simply is the wrong material, use Multimetall.


        Nick

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        • #49
          Well, I must have done it wrong or right, because it certainly works for me. Maybe a Monarch EE has a superior clamping arrangement

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          • #50
            Originally posted by daryl bane
            Well, I must have done it wrong or right, because it certainly works for me. Maybe a Monarch EE has a superior clamping arrangement
            It depends on which Moglice you used Daryl. There are 5 different formulations, and the Teflon/Epoxy "Moglice 1000" is almost as slippery as Turcite, in my experience.

            The original Moglice "FL/P" is Molybdenum disulfide and graphite, and is a lot less slippery.
            Last edited by lazlo; 09-07-2010, 11:20 AM.
            "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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            • #51
              There is only one Moglice. The FL, FL/P & P is only the viscosity "Flüssig, pastِs". The one with high teflon content is ABCoating (air bearing coating).

              http://diamant.ph/en/products/moglice/versions/


              Nick

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              • #52
                Originally posted by MuellerNick
                There is only one Moglice. The FL, FL/P & P is only the viscosity "Flüssig, pastِs". The one with high teflon content is ABCoating (air bearing coating).
                The are 5 formulations of Moglice. Like I said, the original 1986 version is common 2-part epoxy loaded with MolyD and graphite. Moglice 1000 is Teflon based. I've used both, and the Teflon version (which pours like honey) has a much lower coefficient of friction. Moglice 1000 makes a great castable nut -- I poured low backlash nuts for my *cough* RF-30 mill drill. I also used Moglice 1000 for the sliding bushing for my Clausing VariSpeed:

                http://www.moglice.com/lowfrictionwayliners.html

                Moglice 1000 Fluid is a fluid about the same viscosity as the Moglice P-500 above. Moglice 1000 Fluid differs in that it contains Teflon and results in a 25% to 30% further reduction in friction. It also provides added protection against moisture absorption.


                But if the goal is to just shim the tailstock back on-axis, why not use common Devcon? You could scrape both castings flat, spray the opposite piece with mold release, pour the Devcon, and let the tailstock settle. The transverse way should keep it aligned.
                Last edited by lazlo; 09-07-2010, 12:35 PM.
                "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                • #53
                  Moglice 1000
                  Whatever the importer likes to call it. Devitt is just a US-distributor. I gave the link to the manufacturer.


                  Nick

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                  • #54
                    JT,
                    If there is a droop, the job isn't finished. If you have to step in to finish the job, you would have checked everything to see where the job stands. You find the droop, are the slides finished? If so go to the next scenario. Personnally, I would restart the scraping of the slides, and make the correction, that would be the easiest solution. There, most likely, isn't much left to do, but irregardless, I would still do the slides.
                    2nd scenario;
                    If the droop is very little, say .001", yes you may get away with scraping the flat top of the bottom, or the bottom of the top, but why. That's a harder job than scraping the V and flat slides, and you still have to contend with the test bar checks. I've been there and done that, never again. The bottom of the top on my 12"CK wasn't flat, I don't even want to know how it got like that, all I remember from 7 years ago, is that it was a bitch. Mostly a guessing game, as spotting was extremely difficult.
                    On the Series 60 the bottom of the top is not parallel to the spindle, and I made the correction on the V and flat slides of the base casting, plus the spindle was pointing to the rear, after I had spent a lot time scraping the base per Connelly, so it was really a double correction. I discovered this after completing the base, the first time, when I assembled the TS and ran the test bar checks. That was one of the most fussy scraping jobs I've done, but it went pretty quickly.

                    Let me pose a question. Same situation, but it's the carriage, and the cross slide is finished, including the cross feed screw alignment. You find an error in the cross slide alignment to the spindle. Where do you make the correction?
                    Harry
                    Last edited by beckley23; 09-07-2010, 11:50 PM.

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                    • #55
                      Originally posted by beckley23

                      Let me pose a question. Same situation, but it's the carriage, and the cross slide is finished, including the cross feed screw alignment. You find an error in the cross slide alignment to the spindle. Where do you make the correction?
                      Harry
                      Directly fixing the crosslide ways seems to involve less material removal and hassle, even though some things have to be re-done. Cross-slides usually have dovetail ways, and so there are two basic surfaces, plus the screw alignment. The flat slideways shouldn't need anything. Presumably the V/flat is also done, or you wouldn't be even measuring the crosslide. So a direct fix seems appropriate if the metal exists to do it.

                      While I suppose you could fix it with the V/flat, that involve the apron, plus possible lengthwise tilts that might affect compound travel, etc, etc. And, the carriage is usually longer, so any particular angle change needs more thickness of metal removed than on a shorter length of crosslide.

                      So my choice, without more information, would be the crosslide directly. (Assuming there is no error in the headstock alignment, which if you are measuring the crosslide, should be OK)

                      Was your choice of doing the V/flat on T/S based on amount of material removal?

                      The reason I would think about NOT doing that would be "why scrape to 4 constraints, again, when you can do a different surface to 2 only, and have the chance, if there is a lot of error, to mill off the bulk"?

                      Most T/S have only a rim of contact, so the area is not crazy.
                      4357 2773 5647 3671 3645 0087 1276

                      CNC machines only go through the motions

                      "There's no pleasing these serpents"......Lewis Carroll

                      Comment


                      • #56
                        After the cross slide ways, including the dovetails, are completed, and the cross feed screw is aligned, why would you make the correction to the dovetails, which has every possibility of causing an alignment issue with the screw; a tightness in one area of travel and looser the further away from the handwheel, and that's on a lathe without a taper attachment. Think about the issues with a telescopic cross feed screw, which is anchored in the TA. I'm not about to rescrape the dovetails, and will make the corrections on the carriage slides.
                        Back to the tailstock. I'll still recommend doing the corrections on the V and flat slides, and I'll also be monitoring all the important alignments.
                        Harry

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                        • #57
                          You seem to be opposite to me in everything... presumably that makes me "wrong"......

                          As to why?

                          Because, as I mentioned, it is two simple surfaces, to scrape to a limited number of constraints, and , if I understand your statement of the problem, the ONLY issue is the horizontal "aim" of the slide, which is "off" towards either the T/S or the H/S.

                          If so, you probably do not need to do anything to the horizontal slideway, at least not for any alignment correction, just the dovetails. So any issue with the screw can be a left-right issue, and is probably very slight. Of course it could be a problem, but I am assuming the error is not huge.....

                          Otherwise, by attacking the slideways, you may change the alignment of the carriage apron to the leadscrew, both horizontally and vertically, you may tilt the carriage and thus the compound so that it does not track parallel to the spindle when set at 90 deg, etc, etc. Of course that is also a small correction, but the longer length of the slideways means the actual metal removal is more than with the direct correction.

                          If it is big enough to affect the crosslide screw, it will be bigger if corrected at the slideways, I think, so the apron will be affected. And the V angle ensures that there is a vertical component to the issue....affecting those other things.

                          And for the privilege of possibly opening those cans of worms, you get to scrape at least 3 long surfaces to at least 4 constraints (flatness, overall angular positioning (the correction), V angle, relation of V to flat and vice-versa).

                          honestly, it looks like less time and trouble to correct directly. I am looking at it as a business, not as one's personal machine, which of course is not costed the same way. I assume that one would like not to lose money on the job, while also getting a good result to keep the reputation.

                          You asked... that is my answer.
                          4357 2773 5647 3671 3645 0087 1276

                          CNC machines only go through the motions

                          "There's no pleasing these serpents"......Lewis Carroll

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                          • #58
                            While I don't recondition for a living, which I've always found to be a losing proposition, I do use these machines to make my living. You could say I have a vested interest in the accuracy and condition of my equipment.
                            The reality of the carriage is thus; By the time these lathes hit my door there is a good deal of wear in the slides. In order to avoid relocating the gearbox and the right end bracket, the cross slide ways are the first things that gets finished. A few measurements are taken and the decision is made to apply Multifil 426 Way Strip Bearing material, very similar to Turcite, to build height, such that the gearbox and bracket don't have to be relocated. The carriage is than set upside down on the mill, and enough material is taken off the slides to allow for the epoxy, Multifil, and scraping stock. The scraped flat cross slide ways are used as a reference surface for the machine work. After the epoxy has cured, the Multifil is scraped, again the cross slide ways are used as the control surfaces. A level is used on the flat cross slide ways, and the cross slide is indicated against a parallel in the 4 Jaw chuck for that alignment. This is all shown in both threads I linked to earlier. Multifil, and I suspect Turcite, are far easier to scrape than cast iron. I won't use a BIAX on it. Imagine scraping butter with a dull knife, only a little more difficult.
                            I have used these methods on quite a few lathes. There are only 3 lathes that I owned, a 6" Atlas, a 9" SB and a 13" Harrison, that the cross slides were scraped using your method, and only because I was touching up the ways. You're right the effect on the cross feed screw is minimal.
                            Perhaps our differences are a matter of perspective, and stem from the initial condition of the machine, and what has to be done to achieve our goals. You can rest assured that I don't like doing any more work than what's necessary, as far as scraping is concerned.
                            Harry

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                            • #59
                              I sure don't do it for a living...... I'd starve.

                              But I am "lazy", and prefer the way that is not as complex.

                              I'm good with doing it either way. Doing the slideways may be somewhat better, more correct, but too much work for me! I think the result in your example would be the same either way, so I take the easier way.

                              Maybe Nick has an opinion? He obviously is oriented to the most correct method. I respect both your opinions. And of course Forrest.
                              4357 2773 5647 3671 3645 0087 1276

                              CNC machines only go through the motions

                              "There's no pleasing these serpents"......Lewis Carroll

                              Comment


                              • #60
                                Maybe Nick has an opinion?
                                The difference is, that Harry suggest using a resin for the carriage.
                                You can align the carriage with setscrews or leaving small islands that you file/scrape/shim to get the alignment of the complete carriage (incl. cross feed).
                                So this breaks the rule "Work from bottom to top" but gets extra credits on the rule "Save time by thinking".

                                Moglice (etc.) is very easy and quick to scrape by hand and a Biax would be simply the wrong tool. If you did your casting right, you only need minor or no adjustments and often enough you are done after scraping over the surface for oil pockets and cutting a groove for the oil.


                                Nick

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