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  • Benchmaster progress

    Got some time to work, and am starting to get some more contact on the column way fronts....

    As-received.....


    last spotting... still plenty to do


    I've been alternating the small granite flat with a straightedge, both "X" and along the length. it was considerably "out".
    2801 3147 6749 8779 4900 4900 4900

    Keep eye on ball.
    Hashim Khan


    It's just a box of rain, I don't know who put it there.

  • #2
    What kind of scraper are you using?
    "Patriotism is the last refuge of a scoundrel"

    Comment


    • #3
      That looks like something that could be done in a surface grinder and then flaked if wanted.
      Andy

      Comment


      • #4
        Originally posted by vpt
        That looks like something that could be done in a surface grinder and then flaked if wanted.
        Part of it could be easily..... the mating part might not be so easy...... no doubt could be done.

        a) don't have one with the travel to do this. Do know someone who mentioned they have an 18" unit....

        b) there are a LOT of parts and angles to be done, contracting out could get expensive.... as in more than the machine is worth.

        C) Flaking..... I dunno who did the hack job of flaking this one, I assume the previous owner. Flaked it, failed to scrape or grind first. I didn't like the flaking job anyway. I prefer a "frosted" appearance, which is patterned scraper marks, NOT deep gouges. Thankfully, the existing "flaking" was not at all deep.
        Last edited by J Tiers; 12-28-2010, 07:47 PM.
        2801 3147 6749 8779 4900 4900 4900

        Keep eye on ball.
        Hashim Khan


        It's just a box of rain, I don't know who put it there.

        Comment


        • #5
          Looking good Jerry!

          Is there any way to tip the column on it's back so you can scrape horizontal?

          When I scraped the reference flat on my Millrite column, it was exhausting scraping vertical up. I ended up buying a Biax to do it -- I don't think I'd have the patience or stamina to do scrape two entire dovetails in that position.

          "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

          Comment


          • #6
            Yes, I could, but I already bolted it down, so I really don't want to.

            It's not that big, about 18"-20" ways, so its at a reachable position. I almost LIKE scraping this way, the dust FALLS OFF, and a light wipe after the de-burring is all it takes.

            horizontal is probably still better, ergonomically, but this isn't so bad, since the thing is quite solid on its base. Maybe I will think again when I do the dovetails, but I need to make some fixtures for that first.

            For this column, I want to go for the "diamond pattern frosting", we'll see how it goes..... I just love that "Brown & Sharpe catalog" look. I THINK I know in my head how to do it, and we'll see if I can translate that into muscle movement..

            But the alignments have to be right, I want it right even if it doesn't get "frosted". Now I need to dig around for my longest parallel so I can start checking the alignments as I go. The basic marking is now just about all over the surfaces, so it is refining time if it shows up within spec.

            Are you scraping the whole Millrite? Just that column looks like a "job o work".
            2801 3147 6749 8779 4900 4900 4900

            Keep eye on ball.
            Hashim Khan


            It's just a box of rain, I don't know who put it there.

            Comment


            • #7
              Well, since I got to a place with a decent flatness, I could test the ways for alinement to the spindle.

              Setup #1


              left side


              Right side


              Clearly not good, I'll have to scrape a lot off to get this within my goal, which is around 0.001 or less. It's around 7" across the ways, and I want no more than 0.002" in 18" error. So a bit under 0.001 should do it.
              2801 3147 6749 8779 4900 4900 4900

              Keep eye on ball.
              Hashim Khan


              It's just a box of rain, I don't know who put it there.

              Comment


              • #8
                Now the vertical alinement, using the best parallel I can find of a decent length. Could be longer and be better, but I haven't made that part yet.

                Setup


                Upper check


                lower


                looks like some work there also, I'd like that nearly dead-on, since the same 0.002 per 18" applies, and the length of measurement was not so long.

                So it's off to scrape the right side heavy, and the tops of both heavier while taking a bit off the right side of teh left way, to allow the plane to turn a bit to the right.
                2801 3147 6749 8779 4900 4900 4900

                Keep eye on ball.
                Hashim Khan


                It's just a box of rain, I don't know who put it there.

                Comment


                • #9
                  So, now quite a bit of scraping has been done.... taking off just a couple thou is a lot of work, actually,. Makes me laugh when I see someone afraid to use oil and abrasive paper to clean rust off ways.

                  Left side


                  right side


                  Not so bad. if I do the right one heavy and left light as I flatten them, should come in. I'm not going to measure the vertical until the flatness improves.

                  Spotting, just to see where we are.


                  Hmmmm work to do.

                  Just for grins, here's the pile removed , most all from right hand side, in bringing the way down 0.002 or so.
                  Last edited by J Tiers; 12-31-2010, 08:01 PM.
                  2801 3147 6749 8779 4900 4900 4900

                  Keep eye on ball.
                  Hashim Khan


                  It's just a box of rain, I don't know who put it there.

                  Comment


                  • #10
                    You're moving along quite nicely. Bet with a few extra cycles, you could do better than .002"/18".
                    Harry

                    Comment


                    • #11
                      Originally posted by J Tiers
                      Part of it could be easily..... the mating part might not be so easy...... no doubt could be done.

                      a) don't have one with the travel to do this. Do know someone who mentioned they have an 18" unit....

                      b) there are a LOT of parts and angles to be done, contracting out could get expensive.... as in more than the machine is worth.

                      C) Flaking..... I dunno who did the hack job of flaking this one, I assume the previous owner. Flaked it, failed to scrape or grind first. I didn't like the flaking job anyway. I prefer a "frosted" appearance, which is patterned scraper marks, NOT deep gouges. Thankfully, the existing "flaking" was not at all deep.

                      Its looking good, your doing a great job! I haven't ever scraped anything so maybe the process is easier than what I am thinking it is. Maybe some day when I get a machine worth restoring I'll get into it. Now I make more mistakes than I care to mention so any flaws in the machines are covered up by my work.
                      Andy

                      Comment


                      • #12
                        Not owning or having read MTR.... What do you have mounted in the spindle to clamp the test indicator to? If that's a commercially produced MT stub or drill chuck arbor, can you be certain of its concentricity? How can you be certain that the spindle bearings aren't affecting your indicator reading as you rotate the "fixture to access the other column way?
                        Just looking for a better understanding of your assessment procedure.

                        Comment


                        • #13
                          Originally posted by Rosco-P
                          Not owning or having read MTR.... What do you have mounted in the spindle to clamp the test indicator to? If that's a commercially produced MT stub or drill chuck arbor, can you be certain of its concentricity? How can you be certain that the spindle bearings aren't affecting your indicator reading as you rotate the "fixture to access the other column way?
                          Just looking for a better understanding of your assessment procedure.
                          1) Concentricity of any part of the holder is unimportant as long as it is steady and does not change when moved. Since I got very consistent readings, it didn't change.

                          2) Spindle bearings (tapered roller in this case) could make a difference, and I checked for that right away. Since this unit has the spindle in a sort of quill, or "carrier", that in turn is clamped to the column, I could unclamp, turn the "carrier", clamp, and re-check. That turns the outer races vs the rollers and spindle. Turning 180 deg in small increments showed very closely similar results at all points, so the bearings were not a concern. I also had the arm off a time or two, and back on at relatively random orientations.

                          Looking at the geometry, the distance between bearings is less than 2:1 vs the longest lever arm. So to create an error of 0.002, the bearing system would have to be "out" 0.001, which is a lot.

                          Then also, the longer lever arm has a very small arc through which it turns in the test, perhaps 1/6 or 1/8 turn. If the bearing system is "out" 0.001 in that small arc, it has an extremely serious wobble.
                          2801 3147 6749 8779 4900 4900 4900

                          Keep eye on ball.
                          Hashim Khan


                          It's just a box of rain, I don't know who put it there.

                          Comment


                          • #14
                            Got some more time into this .....

                            latest left side


                            latest right side


                            Not perfect, but within my requirements.

                            I probably had it closer at one time, but ended up overshooting a little on the left way, and had to take off more than I wanted to. Then I was pretty unwilling to do anything drastic on the right.

                            latest top


                            latest bottom


                            I'm calling that good......

                            I think it's time to do the column guiding way and gib way now. I may have to make some fixturing to measure them.
                            Last edited by J Tiers; 01-09-2011, 01:12 AM.
                            2801 3147 6749 8779 4900 4900 4900

                            Keep eye on ball.
                            Hashim Khan


                            It's just a box of rain, I don't know who put it there.

                            Comment


                            • #15
                              No it is not perfect but within the red range of spot-on.
                              It looks like the rule you are using to messure is prefered over a camelback.
                              This one you can clamp down.

                              Comment

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