Announcement

Collapse
No announcement yet.

Lathe Leveling

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Lathe Leveling

    Greetings Folks,

    Was wondering if anyone here might remember an article in one of the home shop magazines from around 15 years ago about an unorthodox method for leveling a lathe bed that didn't require the use of an expensive precision level. As near as I can remember it involved a bar several feet long pivoted from an overhead support with a lead weight attached to the free end and a simple dial readout of some sort attached to the upper end of the bar. I thought it was in Live Steam but a search of my back issues didn't turn up anything. Maybe it was in Modeltec. I would like to locate a copy of the article if possible.

    Mike

  • #2
    "Rollie's Dad's method" ?

    Comment


    • #3
      Originally posted by Tony Ennis View Post
      "Rollie's Dad's method" ?

      Oh boy, here we go again ...
      Cheers,
      Gary

      Comment


      • #4
        I can't remember what I had for lunch!!!

        JL............

        Comment


        • #5
          I believe it was in either HSM or MW, and it was indeed a pendulum method.

          I can't understand it being really very sensitive, not without such large supports etc as to possibly affect the result. But I don't remember enough of it to discuss it in an informed way.

          Originally posted by JoeLee View Post
          I can't remember what I had for lunch!!!

          JL............
          If we get into another session of RDM, we may all get another look at what we had for lunch.......or dinner.....
          1601

          Keep eye on ball.
          Hashim Khan

          Comment


          • #6
            If we're talking about some kind of sensitive mechanical level, then it would be a base and column, with the pendulum hanging from the top and the pointer hovering over a bit of a scale. The base is set on the ways- if built properly it's not too long to fit between the lathe and the ceiling- and the relative position of the pointer is noted. You repeat the test at each end of the bed, and you shim the mounting bolts until you get the same reading at either end.

            In a variation on this, there's a mechanical amplification added to spread out the small deviations that may exist into a wider reading.
            I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

            Comment


            • #7
              Theres a Utube video of a guy trying it.

              http://www.youtube.com/watch?v=wANmXuwowqw

              Comment


              • #8
                Not enough info: What make lathe, swing, etc? How old? What condition? What class of work?

                I looked at the link above. It appears to be based on the pendulum levels used by the Pharoh's stone masons. The YouTube guy demonstrates a very sensible adaption. However his apparatus is subject to error from drafts purturbing the pendulum, it loses sensitivity in proportion to height limitation and the riser tube is sensative to heat input. A hand on one side will warm it leaning the tube sligtly dragging the bob with it. However the aluminum tube conducts heat well and if allowed to settle will soon reach thermal equalibium. If you wish to shorten thermal recovery time wear thick fluffy mittens or barbecue mitts when handling the instrument.

                The bob's decaying oscillation may be more quickly damped if an aluminum fin is attached that sweeps a magnetic field however the sensitive parts of the apparatus in proximity to the field will need to be made of non-magnetic materials.

                The pendulum level's performance could be enhanced if a more sophisticate pointer and scale is fitted to the bob, maybe with magnification or perhaps some form of inductive sensor could be used. It should be noted that electronic pendulum levels capable of sensing 1 arc second are on the market.

                The idea bears merit if the pendulum length could be shortened and enclosed in a draft and chip- proof enclosure, magnifed optical display: a spherical lens (a clear glass marble) in a cheap pointer laser's light path, mirror the deflected light up the height of the enclosure and fan the magnified travel on an adjustable scale. Pointer lasers, glass marbles and tiny mirrors are cheap, the pendulum apparatus made of shop surplus. Hm, could be made cheap at that but expensive in time. The mind boggles at the possibilities.

                My advice is to spend a little wise money and purchase a precision level you can use in the future because, believe me, a precision level has many uses in a small shop besides leveling machine tools

                Here's a place to start.

                http://www.ebay.com/sch/Manufacturin...recision+level.

                You do not need a used $350 Starrett #199 from eBay or a $750 Starrett #199 purchased new, or $1200 Wyler. Import quality is fine for a precision level for the low-use home or small commercial shop. Their graduations may not be spot-on but their sensitivity is adequate and, if adjusted or used with treverse checking technique, can be easily and consistantly read to 0.001" per foot or better; planty good enough for all but the most persnickity lathes.
                Last edited by Forrest Addy; 02-19-2013, 01:59 AM.

                Comment


                • #9
                  Just get a precision level and save yourself a lot of effort trying to use other methods.

                  Comment


                  • #10
                    I have seen a couple of the Pharoh's pyramids and they seem to be standing up quite well, considering the few thousand years they have been there and the centuries of having bits pilfered off them. Good enough for those guys probably good enough for my lathe.

                    Comment


                    • #11
                      Originally posted by The Artful Bodger View Post
                      I have seen a couple of the Pharoh's pyramids and they seem to be standing up quite well, considering the few thousand years they have been there and the centuries of having bits pilfered off them. Good enough for those guys probably good enough for my lathe.
                      What does that mean? The pendulum was accurate enough, or the ancient Egyptians had Starrett master levels?

                      Comment


                      • #12
                        Here's the link to Rollie's Dad's Method: http://www.neme-s.org/Rollie%27s_Dad%27s_Method.pdf
                        ----------
                        Try to make a living, not a killing. -- Utah Phillips
                        Don't believe everything you know. -- Bumper sticker
                        Everybody is ignorant, only on different subjects. -- Will Rogers
                        There are lots of people who mistake their imagination for their memory. - Josh Billings
                        Law of Logical Argument - Anything is possible if you don't know what you are talking about.
                        Don't own anything you have to feed or paint. - Hood River Blackie

                        Comment


                        • #13
                          Originally posted by SGW View Post
                          Here's the link to Rollie's Dad's Method: http://www.neme-s.org/Rollie%27s_Dad%27s_Method.pdf
                          Waste of time. Don't give sh!t if he's you're personal friend. Over a hundred year of work by Millwrights in setting up and aligning machines says use a precision level, known accurate straightedge, taut wire,etc. If you can't afford to buy a Starrett, Mitutoyo, etc., borrow one, offer to pay shipping and insurance if the lender is far away. Until that time use the most accurate level you own to align the bed, swapping it end for end until the readings are the same.

                          Comment


                          • #14
                            Originally posted by Rosco-P View Post
                            Waste of time. .
                            Why? you don't think it will work?

                            Over a hundred year of work by Millwrights in setting up and aligning machines says use a precision level, known accurate straightedge, taut wire,etc.
                            The conclusion you might draw from that is that if you frequently do this work a 199 Starrett is the quickest way to get the job done, not that this won't work

                            The method, at least the first part checking with the bar, is basically how you scrape a headstock into alignment. It's also not dissimilar from doing a test cut and tweaking the levelling. I can see Rollie's method being of value from someone without a level, or when the lathe is worn to point of not having much confidence on the surface you're placing the level on.
                            in Toronto Ontario - where are you?

                            Comment


                            • #15
                              There has to be an accurate way to do this without a level. Ships have lathes and they roll around in the ocean negating the ability of a level to help at all. During WW II warships took all kinds of punishment from everything from enemy shells to plane crashes and typhoons. Certainly the lathes aboard had to be readjusted after such incidents. Maybe an old veteran navy machinist here can chime in with a method.

                              Comment

                              Working...
                              X