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K O Lee BA-960

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  • K O Lee BA-960

    I'm in the process of restoring a BA-960 tool and cutter grinder. I was wondering if anyone out there has the table tolerance specs. What I'm running into is as I indicate the table there is a difference of about .001 from left to right. The right side indicates slightly higher. Also front to back has a difference of about .002. SInce this machine is almost in unused condition I have to assume that it is within factory specs but would like some opinions.

    TNX... Joe

  • #2
    Hey Joe, welcome to the group...

    As you may have noticed by now, the thread now running "my new toy" is about a 960 KO Lee posted by long time member Lane Sisson. Hes has a 'day job' and wont be home til this evening, but no doubt he can give you some pointers. He often has someone hes emailing info back & forth with -----
    If everything seems to be going well, you have obviously overlooked something........

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    • #3
      Bill,

      Thanks for the quick reply. I will try to check in on a daily basis. I can't find any info on the KO stuff and as all may know whats left of them has been taken over by LaBlonde and there are no technical expersts left.

      Thanks........ Joe

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      • #4
        I have the exact same model as yours, and it had roughly the same problem, but maybe alittle worse. I found that the sliding v-ways and bottom table were very accurate, but the adjustable compound table that sits on top was the culprit. It had a definite twist, but looked original. I cured the problem by scraping in the top of the bottom table and then both sides of the compound table. Quite a bit of work. Probably not the answer you were hoping for, but thats how I fixed mine.

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        • #5
          Darl,

          Thanks for the reply. I would like to post some pictures of mine but don't know how to do it. I think your correct in saying that the top table is the culprit. I'll have to take mine off and indicate it on the surface plate to know for sure. Also than I will be able to indicate the surfaces on the sub table where it sets. The other problem is when I tighten down the center set screws it pulls the center of the table down about .002. I guess the graduated dial under the table center is not the same height as the sub table ends. Given all these inaccurate points a set of matched tailstocks would seem worthless.

          Joe..................

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          • #6
            Your situation is almost exactly what I found with mine. The top table sits on three points, on the bottom table. They should be all the same height, at least, I think they should. On mine, they were all over the map, and I don't think the top table had ever been off, and no indication of wear. Actually I scraped the top table first square and parallel and used it as the master to spot the three platforms on the bottom table. I scraped all of the platforms down to equal height and that made a huge difference. Problem solved. Not to add to your worries, but I had to scrape in the "matched" tailstocks as well to really get them dead on with each other.
            Last edited by daryl bane; 08-17-2009, 01:45 PM.

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            • #7
              The top swivel table is warped .So is mine For cutter grinding it want matter only if you try to mount and use a magnet for surface grinding . Had same problem with my little A 600 ko lee But it I re ground flat . My try to find some one with a big grinder and get the one on my 960 re ground easer than scraping. The numbers you give do not sound bad mine is worse . I would live with that.

              daryl bane could are would you give me the dimensions of that bracket mounted on top of the spindle housing of your grinder . I do not have that bracket and want to build one like it with the t slot . thanks Lane
              Every Mans Work Is A Portrait of Him Self
              http://sites.google.com/site/machinistsite/TWO-BUDDIES
              http://s178.photobucket.com/user/lan...?sort=3&page=1

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              • #8
                does this T&CG table move on roller elements or V ways?
                .

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                • #9
                  My 960 is v-ways, I'm sure Joe's is the same. Lane- I will take a pix with some dimensions and post it here , if thats OK.

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                  • #10
                    Thanks daryl that will be big help. mine is also v and flat way . They made a ball bearing way and a hydrostasatik model also . I know not spelled right
                    Every Mans Work Is A Portrait of Him Self
                    http://sites.google.com/site/machinistsite/TWO-BUDDIES
                    http://s178.photobucket.com/user/lan...?sort=3&page=1

                    Comment


                    • #11
                      Hey Guys,

                      Thanks for all the replies. From what it sounds like those sloppy tolerences were just fine with KO Lee. Every one seems to have the same problem. It's not easy to get all points perfect. When I take my top table off and indicate it I'll post the results but being warped was my first guess due to the castings moving over time. Maybe they were not well seasoned before they were cut. By the way the castings are terrible looking, I've seen better looking vulcanic slag. Also what I have noticed is the older machines 1960's era have much better castings and tolerances than the newer ones, 1980 and up. I'm not real happy about the way the colume moves either, mine is the one with the spring loaded keyway.
                      The matched tailstocks are a whole nother issue.

                      TNX...... Joe

                      Comment


                      • #12
                        Update On K O Lee BA-960 Table Flatness

                        After removing the top table and indicating it I found it to be flat all the way around within .0003. So it's not warped or twisted. Good enought for me. Where the problem lies is in the sub table on the right side where the top table sits. I have indicated both left and right sides. The left side is flat when the saddle is moved in and out. The right side rises about .002 as I move the saddle out. Thats where the poblem is. The factory has a .004 shim under the right front saddle way and base. So that tells me they new and tried to correct the problem. What seems to be happening is when the saddle is moved out it's actually climbing up and when moved out if you press on the table you get about .0015 in dial movement. This is starting to put a twist in the saddle. Trying to correct one problem just created another. Shimming is not the answer. Since I have no experience in scrapeing in a machine I guess I'll have to live with it.

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

                        Comment


                        • #13
                          I can't quite picture the compound table for that particular cutter grinder, but I have one of the Rockwell-Delta Toolmaker's with what I believe to be a similar swivel table. I was going to suggest flipping the table and bolting it down and just grinding the bottom in place, but it struck me that most of these are longer than the work envelope of the grinder, so that they can hold centers out beyond the limits of travel, for making (for example) reamers up to the full travel length.

                          It's a bit wierd to think about something as capable of precision as a tool and cutter grinder or surface grinder with a "flaw" like that, but the fact that it's a single point operation to grind something, can make this less of an issue.

                          Paul
                          Paul Carpenter
                          Mapleton, IL

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                          • #14
                            Sparking

                            Joe.

                            I think you are worrying needlessly about problems that may not be problems after all as they can be over-come quite easily and successfully so that your grinder will work very well.

                            It is quite possible - and normal - to "adjust" any perceived "errors" "out" so that while they will not be eliminated, they can be countered - easily and accurately.

                            It seems that your saddle "X" and "Y" ways are in very good order when the pivoting table clamps are eased/slackened-off. That is the most important thing of all.

                            The "twist" or "warp-age" in the pivoting table is of no concern. The important thing is that it does not impart any distortion into the saddle.

                            Slacken-off all the pivoting table clamps. Measure the gaps under the pivoting table at the clamps (use feeler-guages). Insert shims to suit at the clamp positions. Fasten the clamps. The pivoting table is now clamped to the saddle without trying to distort the saddle nor will it impart any stress to the saddle.

                            Mount the centres on the pivoting table. Get a good quality round and straight test bar with both ends accurately centred. Place the test bar between the centres. Put a test indicator base on the saddle and then put the indicator (a good Test Dial Indicator - TDI - one calibrated to 0.001" is fine) onto the front of the test bar. Set the TDI needle to zero. Run the table left-right and note the TDI deflection difference. Loosen the pivoting table clamps and adjust/pivot the table until the deflection is zero-ed. Clamp the table and re-check the TDI. Re-adjust as necessary. If OK, the centres are set correctly.

                            Grinder centres and table slots are not all that accurate at all as they rely on adjustment to correct for any errors.

                            Now run the TDI on the top of the test piece (between centres). If if the defection difference does not exceed 0.010>0.020" (yep - that much) you are OK as most times you will be grinding from the front or back - not the top. I will be surprised if the error is more than 0.002>0.005" though.

                            Now onto the magnetic chuck.

                            I will assume that you have a magnetic chuck that came with the grinder. If not or if you are getting a new chuck - let me know and I will guide you through installing it.

                            Put the chuck onto the pivoting table and mark the position for future use and reference.

                            With the chuck clamps free, use feeler-guages to find any gaps between the chuck base and the table. Insert shims to suit. Put the TDI onto the top face of the chuck and get the TDI deflections as near equal at each corner and at the centre of the chuck face as you can. Adjust the shims to be both a neat fit under the chuck (see previous) and with the deflections as near equal at opposite corners of the chuck as you can get them. Now clamp the chuck to the pivoting table.

                            You now have the pivoting table and the chuck mounted securely such that no distortion stresses are imparted to the saddle.

                            Now, with a "coarse" grinding wheel mounted on the grinder spindle - dress the wheel.

                            Now take a series of light (0.001") cuts across the chuck face until there is just a small bit left un-ground (this is called a "witness").

                            Let the chuck cool down to ambient (shop) temperature.

                            Re-dress the wheel.

                            Now take light (0.001") cuts on the face of the magnetic chuck until there is still just a slight "witness" left.

                            Now, without down-feeding the wheel, keep grinding - at the same setting - all across the chuck until there is no visible sparks from the grinder wheel. This is called "sparking out".

                            Your magnetic chuck is now "ground in" and is very accurately parallel to the saddle "X" and "Y" ways/guides with no distortion or stress applied from the distorted pivoting table at all.

                            Your grinder is now very accurately set up and ready to go.

                            Whether you have the pivoting table (re)ground or scraped-in is entirely up to you. Not doing them will not upset the accuracy of the set-up at all.

                            Start grinding and let us know how you get on.

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                            • #15
                              Update #2 On K O Lee BA-960 Table Flatness

                              After indicating the top table resting points I went ahead and indicated the center graduated disc or what ever you want to call it. In my first post I had mentioned that when the two locking set screws were tightened down it pulled the top table down a bit over .002 in the front and about .001 in the back. A closer look at the sub table where the graduated disc mounts has revealed that the disc actually slants tword the front of the table. Here is why........ After I took the disc off I found that under it the table was milled. That means during the manufacturing process at KO Lee there were two operations done on the sub table. 1) they either ground the entire top and edeges first and 2) then they moved the table to a mill and milled the round area where the disc mounts. And what do you think happened??????? The table was not accuratly positioned relative to the ground surface and the milled area was slanted. This is what happens when you move things from one set up to another. If I was the engineer in charge of this process I would have ground the table top with the disc bolted in place ensuring that all 3 surfaces were flat. K O Lee Sucks !!!!
                              Anyway, my fix is to grind the round spot in the table where the disc sits. I can grind that on the machine since it's only about a 6" dia. circle in the center of the table. Then I will shim under the disc to meet the height of ends where the top table sits. That should cure the problem.

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

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