Announcement

Collapse
No announcement yet.

yet another "removing stuck chuck" question

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

  • yet another "removing stuck chuck" question

    Got a "nice" LW dividing head today.

    Cleaning it up, I found that it does have the inevitable one serious problem.

    The chuck (1 1/2-8, apparently) is stuck, and isn't wanting to come off. Looks like it might have some rust in that area, although the rest of the "rust" was really just discolored and solidified grease or oil.

    I have various concoctions for loosening rust, P'blaster, etc.

    The question is how to apply force without risking damage to the worm setup. I don't think I want to pull the spindle if I don't have to, as it's not loose, seems OK. I'd have to take off the gear, and the rear nut, etc, which seems excessive....

    I can set up on the spindle lock, but that doesn't seem to make it particularly any safer to reef on or "tunk" on the chuck (or on a piece of hex clamped in it, actually). I kinda need to get the chuck off for cleaning and/or disposal, I think its junk.

    Not much spindle sticking out....

    Ideas?
    1601

    Keep eye on ball.
    Hashim Khan

  • #2
    I think you are right in not wanting to risk damaging the worm. If there is enough spindle available behind the chuck (1/4" or so) I would try to fabricate a strap wrench with steel strap and a piece of stock of the same width.

    Of course, you should soak it in your favorite penetrating oil for a while first.

    Paul A.
    Paul A.
    SE Texas

    Make it fit.
    You can't win and there IS a penalty for trying!

    Comment


    • #3
      Can you disassemble the chuck in place? If you can remove the gear sleve, thread and jaws, you will have easier access to the back of the chuck. It may be open the the threads or you may have to drill into it. Access to the other end of the thread will allow you to try lubrication first. Failing that, I would try cut the chuck body in half without going down to the threads.

      Comment


      • #4
        If your L&W dividing head is like mine,then the worm is on an eccentric which which can be rotated out of mesh with the worm gear and consequently pulled out of the housing.

        It's pretty straight forward except for two set screws in the top of the housing that are perpendicular to the worm shaft. Their function is to keep the worm shaft bearing,which contains the eccentric,where you set it.

        There is no roller bearing on the spindle,just bare metal to metal.The back bearing is just a straight bore while the front big bearing is tapered.The lock is just a screw pushing against a brass plug that pushes against the tapered bearing.I don't remember whether the thrust bearing is a brass washer or what.

        If it were me I think I would pull the worm out and run one jaw about flush with the OD and flail the hell out of it,in a counter clockwise direction of course and after it was saturated with P oil.

        Jim W.

        Comment


        • #5
          JT: Does the worm have a little bit of backlash to work with ... if so how about if you tighten the lock with the backlash NOT taken up (in the unscrew direction). Then, apply gentle "impact wrench" style taps somewhere on the circumference with a brass or aluminum bar.

          After a few test "taps" loosen the lock and see if the backlash is still there. If so, the lock protected the worm against the taps ... tap on, continuing to check periodically for the sake of the worm.

          Den

          Comment


          • #6
            drof: I don't think it is like yours. There is just one (double stacked) setscrew in the top, and the other pic shows the plate side has a bolt-on piece.. no sign of an eccentric that I can see.

            As you can see. not much to grab anywhere. Might have to figure out how to get it out so I can hold the spindle.

            In the first pic, the object along the bottom is a 6" rule that didn't get quite in the pic.

            http://img4.photobucket.com/albums/0...y/lwinsids.jpg

            http://img4.photobucket.com/albums/0...ey/lwfrnts.jpg

            Also, looking at the first pic, there is a hole at the bottom. The bracket (one side, not double) has got a hole corresponding. Do you suppose it would have had a detent? Neither hole goes through.

            Thanks
            JT
            1601

            Keep eye on ball.
            Hashim Khan

            Comment


            • #7
              If you are ABSOLUTLY SURE that it is threaded on you can try this. It has worked for me every time.

              To invent, you need a good imagination - and a pile of junk. Thomas A. Edison

              Comment


              • #8
                G.A.,

                Now that's clever! When one sees a good idea no words needed.

                (should put that in the tips book)

                -Mike

                Comment


                • #9
                  And I would if it were a lathe. But that worm and gear has me worrited. I don't want to strip teeth.

                  It is kinda like using back-gear for a lock, which wouldn't be too cool with impacts. Only I can't disengage the gears and use the rotating pulley mass as a counterpoise, as I might with the lathe. There isn't any mass to speak of, aside from the chuck.

                  I am not even too sure how to disassemble the thing further, even though it is pretty simple appearing.

                  And, of course, I have something for it to do, scheduled for the day before yesterday....so a chance of damage isn't really wanted. This stuck chuck was a surprise I didn't need.

                  I figured I could get it off and put a good chuck on it, grease and oil it, and get going. A full clean and so forth could wait until I had cut the one gear I need to cut....
                  1601

                  Keep eye on ball.
                  Hashim Khan

                  Comment


                  • #10
                    Mike,
                    One pull of the trigger is all it takes (about 30 seconds) The last time that I had to remove a stuck chuck was for a friend. He had got a bit hyper before calling me and had broken 4 teeth off on his back gear. He almost cried when he saw how easily it came off with the air chisel.

                    Neil can use it in the tricks book if he likes.
                    To invent, you need a good imagination - and a pile of junk. Thomas A. Edison

                    Comment


                    • #11
                      JT,

                      Would you be willing to put some heat to it?
                      If I understand correctly, you don't care about the chuck.

                      Comment


                      • #12
                        <font face="Verdana, Arial" size="2">Originally posted by Mike Burdick:
                        JT,

                        Would you be willing to put some heat to it?
                        If I understand correctly, you don't care about the chuck.
                        </font>
                        That is a possibility. I THINK the chuck is bad, but won't be certain until its off and I can disassemble it sometime. Won't come apart now, can't get to the screws with enough torque as is.

                        My experience with heat removing things has not been good. Basically it has not worked well in this sort of situation for me, at least not as far as differential expansion etc. Everything heats together.

                        Maybe heat will just loosen the "crud bond". That does sometimes work, depending.

                        So long as it isn't galled on it may be fine after soaking longer, too.

                        But I can't see how to get a good torque on it.

                        The ID is a taper, probably B&S, which I have no taper tooling for. I suppose I could make an expanding arbor, or draw-in piece, with a hex or hole thru etc.

                        But I would be a bit afraid of expanding the spindle though. The piece might take quite a bit of drawing-in to withstand the larger lever arm of the OD thread, and it will have to come out again someday!

                        Hmmm, its coming off, I just dunno yet how. Hopefully I won't have to turn the whole dang thing off the spindle. Its about a 5" chuck.


                        1601

                        Keep eye on ball.
                        Hashim Khan

                        Comment


                        • #13
                          J Tiers,
                          If you tighten the lock on your dividing head you won't hurt the worm gear with the air chisel. It is the high speed rapping that does the job not brute force. The fellow that I mentioned earlier had put a 2x4 in his chuck and hit it with a 3 lbs hammer. (no wonder he broke the back gears) A strap wrench around the spindle pully is all that it takes to hold it for the air chisel.
                          To invent, you need a good imagination - and a pile of junk. Thomas A. Edison

                          Comment


                          • #14
                            Brilliant idea.
                            The picture if the air chisel makes me flinch because there's no board on the ways. Of course it's just a photo to show the idea, you probably weren't actually using it then?

                            Comment


                            • #15
                              That is excellent George. I will keep that in mind.

                              JT,

                              I don't think you need to worry about the worm. Each hit of the hammer is no more than a light tap. Think about it, the mass of the piston in the air hammer is only a few ounces. I bet it works just fine. Jam the worm with a hardwood wedge.
                              Free software for calculating bolt circles and similar: Click Here

                              Comment

                              Working...
                              X