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Sjogren Speed Chuck- zero settable?

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  • Sjogren Speed Chuck- zero settable?

    I'm looking at getting a Sjogren or Sjogren-Hardinge style "speed chuck", like this...



    For one of my lathes. The one I'm looking at is well-used, and I'm wondering if they're zero-settable, like a "Set-Tru" chuck. None of the admittedly thin documentation I can find about them says anything about it- near as I can tall, they're made concentric at the factory, and if they ever wear off-center, presumably you're supposed to grind the taper back into shape.

    Anyone know for sure?

    Doc.
    Doc's Machine. (Probably not what you expect.)

  • #2
    I think you're right about them not being adjustable. The Jacobs Flex collet holder that works like these can be tapped into center but not these. I could pop the back off mine for a look-see, I'll try that this morning.

    Later: it's not adjustable. The pins that hold the pinions come in from the front half, if you shifted the halves the gearing would get wonky. I took photos and will post when I don't have to go through the machinations of saving them into a local album that always drops them after a 'save'.



    Last edited by rkepler; 03-28-2017, 03:21 PM.

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    • #3
      They don't adjust, but there's no reason to think that they might wear unevenly. What's your reasoning?
      Peter - novice home machinist, modern motorcycle enthusiast.

      Denford Viceroy 280 Synchro (11 x 24)
      Herbert 0V adapted to R8 by 'Sir John'.
      Monarch 10EE 1942

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      • #4
        Is this for your CNC'd lathe?

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        • #5
          Originally posted by Peter. View Post
          They don't adjust, but there's no reason to think that they might wear unevenly. What's your reasoning?
          -No 'reasoning', it's just that in this case the price is "suspiciously low", making it both very tempting, and making me wonder "what's wrong with it?"

          But they're simple enough devices that the only thing I can see being wrong is either problems with the gears, or wear on either the spindle face or the collet face. I can theoretically lightly regrind the collet taper, if necessary, but began to wonder if they were, in fact, adjustable.

          Doc.
          Doc's Machine. (Probably not what you expect.)

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          • #6
            Originally posted by Doc Nickel View Post
            -No 'reasoning', it's just that in this case the price is "suspiciously low", making it both very tempting, and making me wonder "what's wrong with it?"
            The threads for the collet end on the central gear can be stripped (I've seen that) and there can be enough wear on the handwheel that it rattles annoyingly. The latter is a lot more common with the 2J collet holders, for some reason.

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            • #7
              Originally posted by reggie_obe View Post
              Is this for your CNC'd lathe?
              -No, I have a full 5C setup for that. The one I found fits an L1 taper, and I'd been thinking of picking up something like that for the big Springfield. I do a lot of collet work, and while theoretically I could fit a 5C closer to the Springer, it'd take some custom work, probably a custom-made extended drawtube, and likely a very expensive, possibly even custom-ground spindle nose adapter.

              I'd been kind of hoping to find a 3J or even 22J chuck, since the Springfield is a fairly big lathe, but the one I ran across is a 2J, which is still a bigger capacity than a 5C.

              Doc.
              Doc's Machine. (Probably not what you expect.)

              Comment


              • #8
                It seems that the original question has been answered in a satisfactory manner, so I don't feel bad about this thread hijack.

                Looking at the photo in the first post, it seems like this brand of collet chuck comes with three different nose styles; plain, taper, and threaded. I am curious, why are different noses needed? I can perhaps see some need for the tapered nose as it may offer slightly more clearance in some (a very few) cases, but I am really interested in why would you need an externally threaded one. What is the justification for these three styles?



                Originally posted by Doc Nickel View Post
                I'm looking at getting a Sjogren or Sjogren-Hardinge style "speed chuck", like this...



                For one of my lathes. The one I'm looking at is well-used, and I'm wondering if they're zero-settable, like a "Set-Tru" chuck. None of the admittedly thin documentation I can find about them says anything about it- near as I can tall, they're made concentric at the factory, and if they ever wear off-center, presumably you're supposed to grind the taper back into shape.

                Anyone know for sure?

                Doc.
                Paul A.
                SE Texas

                And if you look REAL close at an analog signal,
                You will find that it has discrete steps.

                Comment


                • #9
                  Originally posted by Paul Alciatore View Post
                  Looking at the photo in the first post, it seems like this brand of collet chuck comes with three different nose styles; plain, taper, and threaded. I am curious, why are different noses needed?
                  -The middle one is a Hardinge lathe nose taper, commonly seen on the HLV-H and many of their second-op lathes. So it's probably in order to to use "pot chucks" or "step chucks"- oversized 5C "emergency" collets with big heads- upwards of 3" and 4" in diameter. The OD of these are tapered, and fit into a hollow collar that goes on the outside of the spindle, so that when drawn in, that taper does the locking, rather than the smaller 5C taper.

                  Doc.
                  Doc's Machine. (Probably not what you expect.)

                  Comment


                  • #10
                    Originally posted by Paul Alciatore View Post
                    It seems that the original question has been answered in a satisfactory manner, so I don't feel bad about this thread hijack.

                    Looking at the photo in the first post, it seems like this brand of collet chuck comes with three different nose styles; plain, taper, and threaded. I am curious, why are different noses needed? I can perhaps see some need for the tapered nose as it may offer slightly more clearance in some (a very few) cases, but I am really interested in why would you need an externally threaded one. What is the justification for these three styles?
                    The non-plain types match Hardinge spindle and tooling noses. So if you bought a collet closer for an extra-depth 6" collet for your dividing head you'd be able to use it on your lathe on the nose of the 5C closer. I made one with the Hardinge 2 3/16-10 (? hope that's right) thread for my lathe:



                    It takes closers for large collets:

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                    • #11
                      I got a 5C one that had about .001 of runout, which is not that bad, but I scraped in the mating parts and the back that seats against the spindle nose, and I am about .00015 now.

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                      • #12
                        that is impressive work.

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                        • #13
                          As to the adjust ability, as others said, they aren't. I sold a 2J version of the of one of these chucks to a friend. It had a D1-3 mount for his Monarch 10EE. He said it had a couple thou runout. We never could figure why the runout since both the chuck and his spindle are made to precision tolerances.

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