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A very handy gizmo for scraping and general evaluation of equipment

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  • A very handy gizmo for scraping and general evaluation of equipment

    This little item seems simple, and basically it is, but it is ridiculously handy. Already it has suggested to me that the wear I thought was on the lathe is not nearly as bad as I had thought....





    Basically a way to hold an indicator in a fixed relation to one part of the machine, while it is slid along to read the distance to another part. For relative measurements, of course, one would use an indicator or DTI to observe variations.

    In the pictured case I am using it to measure from the carriage ways to the tailstock way, which gives a wear measurement under the assumption that the T/S way is not "excessively" worn anywhere, and particularly not near the chuck, where the T/S cannot even physically be moved.

    However, it could be used to measure to the underside of any way to check gib space, to check crosslide dovetails, or on a mill, to check the relation between the column dovetails, knee ways, etc, etc, etc.

    For most of the measurements that are shown in *Connoley* (the scraping reference book), this thing will do them without the need to reproduce the odd looking frames he schematically shows in the illustrations.

    It is based closely on the "King-Way" alignment tool. This one I made, I think it is smaller than the smallest of the original King type, but I am not sure.

    not too hard to make, except that I was being fussy about making it "anatomically correct" insofar as I was able to determine from pictures. I may or may not add the two level vials that are present on the original.
    1601

    Keep eye on ball.
    Hashim Khan

  • #2
    It seems a simple but effective for detecting wear. Nice work, I like the idea a lot. One question I have is that I don't know how you could tell which set of ways is worn (more). I agree that the tailstock ways should be unworn near the headstock but it seems that as you move away from that area it would be difficult to tell how much wear is in either. It certainly would give a comparative measurement between the carriage and tailstock ways, but as you move away from the headstock both would be worn, probably unequally. How can you tell which is worn and how much? Although the odds are against it, couldn't this device "fool" you and give a near zero change as it travels along the carriage way if the tailstock way were worn nearly the same amount? Doesn't the length of the part that rides the "V" way affect the measurement you get as well? Since it appears the tool contacts the carriage ways at 3 points, the tool would not rock at high points or low points, obviously by design. It seems that a longer part riding the "V" would span low areas and give a false impression of wear at a given point. What am I missing here?
    I can see that if you were to use a straight edge on the tailstock way to insure it's flatness prior to applying this tool you might well get an accurate indication of carriage way wear although it might not indicate whether the front or back way has more wear. My assumption would be that the front way would receive more load and ultimately wear on most lathes, but I could easily be mistaken.
    By the way, is that a Logan lathe bed? It looks familiar, but I guess they all (except Atlas) look pretty much the same.
    Last edited by firbikrhd1; 03-28-2011, 12:08 AM.

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    • #3
      Originally posted by firbikrhd1
      It seems that a longer part riding the "V" would span low areas and give a false impression of wear at a given point. What am I missing here?
      By the way, is that a Logan lathe bed? It looks familiar, but I guess they all (except Atlas) look pretty much the same.
      What you are missing is that the prime use is for checking a machine you are scraping....... to get one part you have not scraped parallel to another which you have already completed..... it is a "relative" measurement. You would always use a straightedge to confirm that some odd compensatory set of errors is not present, but in scraping that is inherent.

      And, the complete instrument includes a pair of precision level vials.... one oriented across, and one oriented along the ways..... they have adjustments to set up an on-scale condition.... Most errors that are present would affect the levels, and so would be quickly detected. I have not added levels yet, and may not. Have not yet decided.

      The pictures are just what was handy to show..... but, for instance, if I had scraped the carriage ways, and now wanted to scrape the T/S ways parallel, this would tell me how much I had to take off, and where.

      Or, on an Atlas, I could check the backside gib way relative to the front gib way with one setup and sliding pass, and I could continue to quickly check it regularly as I scraped, using a straightedge for surface, and the "checker" for orientation of that surface.

      The vertical way of a mill column, which is generally too wide for easy use of mics, is another case, as I mentioned....

      When scraping, one has some "known" surfaces, from which others need a specific relation... it's an easy check, without taking a bunch of measurements with a mic and graphing.

      I might mention that if the errors really DID offset, along the whole bed, on both T/S ways, one might then almost call that "parallel"....... it would be pretty much indistinguishable FROM parallel, as the relation would be constant......

      The use of a straightedge would then show if the compensation is due to offsetting errors, or is a true parallel condition.

      For an evaluation of a machine, a complete compensation is so unlikely that one could assume that a parallel indication is probably close to true..... with the addition of the levels, one across and one along the ways, a really good indication is obtained.

      Yes, a Logan
      Last edited by J Tiers; 03-28-2011, 12:11 AM.
      1601

      Keep eye on ball.
      Hashim Khan

      Comment


      • #4
        Thank you for the detailed explanation. I misunderstood and thought the device would be used to check wear on a used machine. It becomes apparent that if a way surface has already been scraped true this tool would provide an excellent method of checking adjacent ways for comparative purposes. I suppose it could be used to check used machines if, as I previously mentioned, the tailstock ways were first checked with a straight edge to insure it was true. If what i have said is true, it would be a great tool to take along when purchasing a used lathe to get an idea of how much wear is actually on the machine and what level of accuracy might be expected. I have read that Logan lathes, in particular don't seem to show wear on their ways and can appear unworn even if significant wear is present. Apparently, on South Bend lathes the wer is more visible.
        Nice job on the tool, thanks again for the explanation.

        Comment


        • #5
          That's a smaller version of the old Kingway Alighment System, I believe. They came in kits each intended for a size range from small like Jerry's to quite large. The patent app shows a variety of uses. It's a "violin" tool. Its deceptively simple whose utility is greatly enhanced by the skill and ingenuity of the user.

          Here's the patent info. Be patient. It takes a while to load even on high speed internet.

          It's an easy to make but all important item for a scraper hand to have in his armentarium or the toolroom of a middling small machine shop.

          Gerry, could you post a photo of your alignment apparatus with the levels in place?
          Last edited by Forrest Addy; 03-28-2011, 01:24 PM.

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          • #6
            It looks like yet another project added to my to do list. Seems to be well made and an excellent and useful tool. Would you mind posting a few more pictures of other angles so I can get a little better idea of the design? Did you use other clamps or make them all.

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            • #7
              Jerry, where did you get the right-angle connectors? Or did you fab those?
              "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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              • #8
                wouldn it make sence to put the instrument on the tailstock ways and measure to the carriage way, if thats what you want to check?

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                • #9
                  Jerry, didn't someone here or on PM create drawings for the King Way - did you use those or just build from pics?

                  I can see the levels being a useful part of it....the challenge is in getting the ones as used in say the Starrett 199 for an amount that is affordable.
                  .

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                  • #10
                    Originally posted by Mcgyver
                    Jerry, didn't someone here or on PM create drawings for the King Way - did you use those or just build from pics?
                    Peter Verbree, on PracticalMachinist, made a nice set of drawings for the full Kingway Alignment Jig, complete with the level mounts. He told me that he submitted it as an article to HSM Magazine, so we'll probably be seeing it pretty soon.
                    "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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                    • #11
                      When Lathe beds are made, the ways are gang milled on a horizontal.
                      The Lathe bottom ,or feet if you wish have been machined first .
                      This means the top, and ways are cut parrallel to the bottom.
                      then the ways are hardened and ground.
                      When ground, again the ways are parallel to the bottom.
                      because the Milling was done with a gang cutter , all top surfaces are cut at the same time ! This is important !
                      The point is that the surfaces on top, although not a "way" are good for
                      evaluations of the ways. (Just a bit rougher )
                      Using J's instrument (also made my own ) you can measure the tailstock slide ways, AND the unground top surface areas and compare them.
                      If both read the same deviation, you know the tailstock way is unworn, and you automatically know what the wear is in the Carriage way.
                      All these surfaces are measured and charted, and the error can more easily be seen.

                      One lathe I rebuilt had no tailstock wear as it was never used .
                      I was in a small town in Canada and no grinding shop. I took the tailstock off its slide, and mounted a 45 degree angle plate and the lathe top slide on it, then put a die grinder on it and ground the carriage V ways using the tailstock ways for a guide and the slide allowed incremental feed of the grinding wheel. Then it was scraped.
                      Lots of ways to skin a fish.

                      Rich

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                      • #12
                        Originally posted by lazlo
                        Jerry, where did you get the right-angle connectors? Or did you fab those?
                        Made the clamps. Started with 1" square stock, and cut away everything that did not look like a "King-Way" clamp. Could have made them much simpler, but I wanted them to look "original", because it looked harder to do that way. Also they ended up as they are because that is darn near the only way you can make them and be able to close the clamps with a thumbscrew.....

                        I have now made very good friends with several bastards...... of the abrasive type.... two are half-round, and the other is rough but has two safe sides........ And I developed a vise as well.....

                        Did NOT make the thumbscrews..... but may do that, because these that I happened to have in a drawer are really too small diameter.

                        The whole thing was made from photos, I have never seen plans other than the patent drawings, which I think I have somewhere..... Over on PM there were good photos for a while, which I snagged for the project.....

                        Forrest.... I have not MADE the level setup yet, because I don't have level vials yet..... I have a project or two going and wanted the frame for measuring, so I didn't mess around with the vial aspect yet.

                        In use for scraping in pics below.

                        Mill is vertical, not the best position for pics and usage, so the "disk" is not included in the picture. The ball would ride on a disk for flat way measurements. If I didn't need a hand free for the camera, it would be perfectly practical to use it on a vertical way like this, complete with disk.

                        What I am doing here is assessing the left hand (gib) way for its alignment vs the right hand (guiding) way. Incidentally, if you are curious, the gib way stinks.... its out several thou, fat at top, skinny at bottom. Since I basically just flattened the guiding way for good contact (not orientation), it has stunk for alignment for some time, possibly since it was made.

                        if Mr Verbree has submitted it, I won't..... I figured to when I had made the levels, if ever....



                        Last edited by J Tiers; 03-28-2011, 11:50 PM.
                        1601

                        Keep eye on ball.
                        Hashim Khan

                        Comment


                        • #13
                          More pics....

                          The disk and ball. I made the disk, but used a tooling ball for the ball, loctited into the end of a rod. Disk has a conical recess for the ball, and a hole through.




                          The V-way slider.... Which works on inverted V, planer/grinder type V, and dovetails. The key issues are the two fatter sections at the ends, to provide 2 of the 3 points of support, and the slot.



                          Slot is also recessed to provide the 2 supports, and the inside of the split is rounded. it's hard to see the rounding in the last pic, because there is also a chamfer on the end, which distorts it. The rounding is not extreme, it is most on the tips of the "arms".

                          EDIT:
                          I should point out that this photo shows the V-way slider in it's alternate position, for dovetails..... tilted 60 deg. if you look at other photos you will see the alternate position for the "standard" or vertical rod attaching to it.

                          Last edited by J Tiers; 03-29-2011, 01:27 AM.
                          1601

                          Keep eye on ball.
                          Hashim Khan

                          Comment


                          • #14
                            Wow, great job Jerry!
                            "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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                            • #15
                              I rigged up a cruder but similar in function setup for my SB9 some time ago. I used a pair of small v blocks spaced apart with a round bar clamped to the top of each block. The middle of the round bar held the rest of the rig.
                              Before I line bored the headstock on the lathe I took some relative measurements with it.

                              I really like your setup with the tubular V way slider.
                              On another note, I have seen a few examples of "sleds" carrying a cutter or grinder that ride along the tailstock or unworn ways to plane or grind worn carriage ways. Such a measuring tool might be a big help for such a project.

                              Steve

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