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Advice needed to choose QCTP

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  • Advice needed to choose QCTP

    hi guys,
    I got difficulties in choosing the the QCTP for my lathe.

    The compound clamp bolt is a bit unusual, it got extra flare stud at the bottom.
    From my research, it is either very similar (or came form same) production in China to Craftex brand model: CX700 and CX706 (very close in overall dimension)


    the distance from top of the compound to spindle center is 20mm (0.78 inch)
    Max. Swing Over Bed mm 250
    Max. Swing Over Cross Slide mm 140
    Distance Between Centers mm 750

    which should be the best fit: OXA or AXA size wedge type? Also there is MXA size on the wedge type

    or should it be better to use the QCTP italian style or multifix style ?
    If other member may have experience with the same lathe like mine, please share some info



    Here are few picture of the compound bolt with the extra flare stud at the bottom





    Last edited by Steph dexter; 04-12-2017, 03:40 AM.

  • #2
    Mine is almost identical to that. Work out what size Multifix is right for your lathe, then see if the bore is large enough. In my case, I had to enlarge the bottom of the bore to make it fit. Not the full height though because I put a spacer under the tool post.

    All the dimensions and guidelines for determining the correct size are on this image https://www.stahlhalter24.de/images/...rsicht2015.jpg

    If your lathe is between two sizes, then the advice is generally to go for the smaller one. You will see there are two sizes specified for the center bore. The "Bohrung normal" and "Bohrung max".

    I would go through the specifications to work out the right one for you, but looking at the pattern on the top of the compound, it looks like there was a multifix on there before. Just measuring the diameter of the toolpost will tell you what size they were using. It looks a bit on the big side, so the next size down might be more suitable.

    Also, you cannot buy the original Swiss Multifix new. The clones probably all use very similar dimensions, but they may not be exactly the same. So double-check with the specs from your intended supplier.

    Comment


    • #3
      Go for a wedge type system for better rigidity than a piston type system.
      Multifix has bizarre 9 degree increments that don't hit many useful angles and the holders are ridiculously expensive, it's pretty rigid and looks fancy though so if you have B&O Hi-Fi and a Leica camera it might be for you ;-)
      If you benefit from the Dunning-Kruger Effect you may not even know it ;-)

      Comment


      • #4
        Originally posted by Magicniner View Post
        if you have B&O Hi-Fi and a Leica camera it might be for you ;-)
        nicely put. The wedge type suddenly got cheaper in the 'states last year but before the price drop could make it over here some idiots voted for a 20% devaluation so even more I can't afford a QCTP.

        Comment


        • #5
          I had something similar but had the collar turned off so I could fit a multifix clone.
          Yes the holders are expensive, but the nine degree steps are convenient. I can reach most angles I want, can set it at 27degrees for threading and can plop the parting tool in at exactly 0degrees. All this without ever needing to readjust anything back to get it straight.

          If you want to have 100 tool-holders it might not be for you.

          Comment


          • #6
            I should have started my reply with "If you want the Multifix". I didn't intend to suggest that it was the only one to consider. I'm sure all the popular QCTP styles work well.

            B&O Hi-Fi and a Leica camera? That's a low blow Neither for me. I bought the Multifix because Adam Booth and Forrest Addy have both spoken about their preference for it. Considering their years of experience, I decided to follow their advice rather than try to work it out for myself.

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            • #7
              You can use an AXA size tool post. Wedge is better. Careful with the OXA etc sizes - the Imports" are typically aluminum.

              Take out your existing post/collar and replace it with something appropriate to to the AXA. Easy.

              Comment


              • #8
                The "collar" might be part of the casting. That's how mine is.
                Last edited by pinstripe; 04-12-2017, 11:39 AM.

                Comment


                • #9
                  Mill it off (after examining the underside) or bore out the AXA center portion. My Emco had a "collar" but it was inserted from the bottom.

                  Comment


                  • #10
                    Sounds a bit different to mine. The pin is inserted from the bottom on mine as well, but the "collar" in the casting is what retains it. If I milled away the casting, there would be a huge hole. So huge that any new pin would foul against the bottom casting.

                    Comment


                    • #11
                      Here's Forest Addys' review of the original Swiss Multifix system (not Italian Multifix). It is no longer Swiss made. They are now made in Germany, France ,and China and possibly elsewhere. I bought an A series from from Amestra (France) in 2010 together with 10 assorted holders. the quality was a bit iffy in some areas and even included holders marked as made in West Germany (so at least 20 years old). Later I bought 10 more holders from Create (China) they appear to be equal in quality to the originals and considerably less expensive. If I were to do it again I would buy all from Create. The 40 spline post allows you to get into all kinds of difficult corners without the need for a special cutter or unbolting of the post. Anyone who doesn't see the point of the 40 position spine has never used one.

                      http://bbs.homeshopmachinist.net/thr...ultifix+review

                      Phil
                      Last edited by phil burman; 04-12-2017, 02:06 PM. Reason: include ref to Italian Multifix?

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                      • #12
                        Originally posted by phil burman View Post
                        Anyone who doesn't see the point of the 40 position spine has never used one.
                        My Dickson clone has a vertical locking pin hole for useful angles, lots of people don't know what it's for but you make your own locating pin and drill your own locating holes in the base so you can choose 90, 30, 45, whatever is most useful for you, and not be limited by built in divisions. This also leaves you with the option not to locate the locking pin and have absolutely any other angle you want, and still with the option go back to your precise reference angles by dropping the pin back in.
                        Anyone who doesn't see the point of not being limited by their tool holder will probably be using a Multifix ;-)
                        If you benefit from the Dunning-Kruger Effect you may not even know it ;-)

                        Comment


                        • #13
                          Originally posted by Magicniner View Post
                          My Dickson clone has a vertical locking pin hole for useful angles, lots of people don't know what it's for but you make your own locating pin and drill your own locating holes in the base so you can choose 90, 30, 45, whatever is most useful for you, and not be limited by built in divisions. This also leaves you with the option not to locate the locking pin and have absolutely any other angle you want, and still with the option go back to your precise reference angles by dropping the pin back in.
                          Anyone who doesn't see the point of not being limited by their tool holder will probably be using a Multifix ;-)
                          Bump "Anyone who doesn't see the point of the 40 position spline has never used one."

                          Phil

                          PS: Forest says: "The Swiss made product is probably as good as it gets in terms of quality and excellence of design"
                          Last edited by phil burman; 04-12-2017, 03:44 PM.

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                          • #14
                            The 9 degree choices is better than it might be, I suppose, it gives some choices, eliminates some common ones, substituting ones that are "close".

                            Can give you 0, 45, 90, but fails for 29,5 deg, you must accept 27 deg as a substitute. No idea what 9, 18, 36, 54, 63 (not 60), 72, and 81 deg are good for, other than being "probably sorta close to what you want".

                            Are those numbers magic in some way? Or are they just whatcha get when you choose 9 deg increments ( 1/10 of 90 deg, good metric "10 hour day" type thinking)?
                            Last edited by J Tiers; 04-12-2017, 04:45 PM.
                            1601

                            Keep eye on ball.
                            Hashim Khan

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                            • #15
                              I would suggest the AXA wedge type toolpost. Additional toolholders are quite inexpensive. I have no advice about the collar on top of the compound because I don't know how it is made.

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