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  • Stop me if I'm wrong

    So, I inherited a Vertex collet system, honestly don't much need it, but one of the holders has some obvious issues. Looks like a collet spun and galled up the taper in the holder, probably the 1/2" collet as it was galled up inside too.

    I'm thinking the easiest way to fix it would be to stuff the holder in the spindle taper (it has the correct MT3), set the compound to be slightly steeper than the collet taper, and have at the galled part with a carbide boring bar. That will eliminate the galling on that particular part of the taper, letting the collets register further down.

    Tell me if I'm wrong before I start. Lots of pictures follow:

    The set, with the problem holder not shown:



    The good holder, setting a reference:



    Method: I rotated the spindle by hand, found the low spot, then moved the cross-slide to set the test indicator to 0. Then I rotated to the high spot, as shown. Not bad, at slightly over .0005" (according to my cheap dial test indicator).



    Indicating off a 5/8" endmill, had to go off the TIN coating but still not too bad, for what it is.

    Next post for the problem holder...
    Last edited by fixerdave; 07-22-2016, 01:13 AM. Reason: title change
    http://fixerdave.blogspot.com/

  • #2
    I would first try stones to just work down the highs. A mirror finish in a taper isn't necessary for a good bite.

    Comment


    • #3
      The problem:



      The indicator is about half-way up the galling there, so it's not actually that far into the taper.

      And the result of that problem:

      Finger tight:


      And with the closer tightened:


      That seems to be a problem. Basically, when I tighten the closer, the runout jumps.

      So, do I just cut away the galled part of the taper on the mucked holder, or is there something else I should try first?

      David...
      http://fixerdave.blogspot.com/

      Comment


      • #4
        Did you clip the ER collet into the recess of the collet-nut before closing or did you just slip it over and turn it tight? The eccentric recess will force runnout and not let the collet close tightly if not 'clipped' into the nut as designed. Many first time users of the ER- system makes this mistake often damaging their collet holder or collet in the process.

        Here is a good description of what I mean:
        http://www.arceurotrade.co.uk/Catalo...s/ER16-Collets

        To clean up the taper I would happily take a light cut to either with a boring bar or toolpost grinder to clean up the high spots a bit.

        Comment


        • #5
          Originally posted by Guster View Post
          Did you clip the ER collet into the recess of the collet-nut before closing or did you just slip it over and turn it tight? The eccentric recess will force runnout and not let the collet close tightly if not 'clipped' into the nut as designed. Many first time users of the ER- system makes this mistake often damaging their collet holder or collet in the process.

          Here is a good description of what I mean:
          http://www.arceurotrade.co.uk/Catalo...s/ER16-Collets

          To clean up the taper I would happily take a light cut to either with a boring bar or toolpost grinder to clean up the high spots a bit.
          Thank you, I did not know about that. They're not ER collets, but close enough, and that probably explains my frustration in trying to get the above endmill OUT of the collet afterwards. The big one does not have a through hole (the small one does, oddly enough) and I couldn't get the (at the time) stupid thing to release. Now I know the stupid part was me

          On the next shop day, I'll redo my measurements after clipping the collet in properly and see where I'm at.

          For cleaning up the taper... cut the whole thing, or just go a bit steep on the galled part? Or, just hand stone? Seems to me the galling is only on a little part of the taper, so either the taper doesn't actually match the collet properly now, or... maybe it wasn't clipped in when it got galled? Yeah, that makes sense now.

          I guess the original owner was too proud to ask I'm glad I did. Learned something new in the process.

          Thanks for that,

          David...
          http://fixerdave.blogspot.com/

          Comment


          • #6
            It's never going to work so I hate to see you waste time & frustration so send it to me I'll fix it & send it back in due time just like new.

            Comment


            • #7
              Originally posted by flylo View Post
              It's never going to work so I hate to see you waste time & frustration so send it to me I'll fix it & send it back in due time just like new.
              Well... on general principle... no. I'm way too selfish for that

              That said, I'm a little unclear why you want them. I mean, I'm not quite sure what to do with them. The only reason I grabbed the one with a 1/2" collet, and discovered the problem, is that I wanted to use a cutter without a flat ground in it for my Weldon shank holder, and I needed more reach than just using an MT3 collet directly in the mill spindle. That reach thing is just because I'm using round-column junk that doesn't have a knee.

              I mean, all the tapers are MT3, and I've got MT3 collets, so why would I put a collet holder with an MT3 shank in the spindle and then something in the collet? I've got 5C collets, and can see where they have the advantage of being through. A 5C collet kind of chuck makes sense.

              But, quite honestly, what's the point of having a front-closing collet that doesn't go through? I suppose if I had some big machine where the drawbar was hard to reach... mine is "right there," probably faster to use than a collet nut on the holder. I know this is getting off-topic... but it's my thread and I can wander if I want to

              Is there some other advantage to these things I can't see?

              David...
              http://fixerdave.blogspot.com/

              Comment


              • #8
                Originally posted by fixerdave View Post
                Well... on general principle... no. I'm way too selfish for that

                That said, I'm a little unclear why you want them. I mean, I'm not quite sure what to do with them. The only reason I grabbed the one with a 1/2" collet, and discovered the problem, is that I wanted to use a cutter without a flat ground in it for my Weldon shank holder, and I needed more reach than just using an MT3 collet directly in the mill spindle. That reach thing is just because I'm using round-column junk that doesn't have a knee.

                I mean, all the tapers are MT3, and I've got MT3 collets, so why would I put a collet holder with an MT3 shank in the spindle and then something in the collet? I've got 5C collets, and can see where they have the advantage of being through. A 5C collet kind of chuck makes sense.

                But, quite honestly, what's the point of having a front-closing collet that doesn't go through? I suppose if I had some big machine where the drawbar was hard to reach... mine is "right there," probably faster to use than a collet nut on the holder. I know this is getting off-topic... but it's my thread and I can wander if I want to

                Is there some other advantage to these things I can't see?

                David...
                Don't forget, you can get a 3C collet adapter that fits in your spindle, and use 3C collets with a draw tube to give you true through the spindle collet action. Collet chucks, at least the ones I ever used, weren't accurate enough that I could re-chuck a piece and have it stay concentric, regarding making shafts with steps on them for trains. I always went back to the 4 jaw chuck and dialed them in. Just my own experience, and I am sure theres plenty of people with collet chucks that work for them.

                Comment


                • #9
                  Originally posted by RB211 View Post
                  Don't forget, you can get a 3C collet adapter that fits in your spindle, and use 3C collets with a draw tube to give you true through the spindle collet action...
                  So, I take it you also agree that these Vertex collets mounted on an MT3 arbour offer no advantages?

                  Actually, I do see another advantage: My mill spindle is rather large and I can see times where one of these collet holders, especially the small one, could offer greater clearance. Again, that's likely an issue specific to my compromised machine rather than something general. So, extended reach, greater clearance... might use them once every few years. They look so pretty and all... but I don't think I'd have actually bought them, and I'm a cheap Chinese tool junkie.

                  I still think I'm missing something. There has to be some magical purpose to these things I'm totally ignorant of.

                  Maybe if I made my own holder, just a cylinder with a taper bore and threaded on the outside, that I could chuck in my 4-jaw. I could dial it in and it could be through-bore like a 5C. Now, that would be useful. Now, I'm really seeing the advantage of that nose-clip that releases the collet. Sigh... I feel another project coming on,

                  David...
                  http://fixerdave.blogspot.com/

                  Comment


                  • #10
                    Thinking too much about this...

                    So... been thinking about these collets and how to use them, and here's plan C-23:
                    1. Make a custom taper reamer:
                      1. turn a slug of steel
                      2. match the collet taper
                      3. mill in a cutting edge
                      4. maybe harden
                    2. Make a 'soft' collet holder:
                      1. face and turn one end of an aluminum soup-can casting
                      2. turn it down such that it fits comfortably within the standard jaws of a 3-jaw chuck but has a bore that roughly matches the small diameter of the collets.
                      3. drill/bore out a 1/2" or so for clearance.
                      4. basically, that end is now a cylindrical square
                      5. flip it, chucking in 3-jaw, roughly marking jaw 1 for repeatability, and making sure the face is registered against the chuck
                      6. face the end
                      7. turn and single-point thread the outside to match the collet nut
                      8. roughly drill/bore it out to match the small end of the collets
                      9. roughly cut the collet taper with the compound
                      10. using the tailstock, run the above custom reamer in to a set depth

                    At that point, I've got a through collet chuck that is as true to the lathe as I'm ever going to get.

                    The next time I want to use it:
                    1. chuck it in the 3-jaw
                    2. face off a bit
                    3. run the custom reamer down to the prescribed depth

                    And, at that point, I've got a through collet chuck that is as true to the lathe as I'm ever going to get. Just a little shorter than it was before.

                    At some point, I'll run out of collet holder and have to make another. But, it doesn't actually sound that hard to make if I've got a reamer for the taper angle. I mean, making the taper reamer sounds a lot harder.

                    Does this make sense?

                    David...
                    http://fixerdave.blogspot.com/

                    Comment


                    • #11
                      Originally posted by fixerdave View Post
                      I mean, I'm not quite sure what to do with them. ... I mean, all the tapers are MT3, and I've got MT3 collets, so why would I put a collet holder with an MT3 shank in the spindle and then something in the collet?
                      Well, you could put your collet holder with the MT3 shank in your tailstock, and use live tooling in the headstock, for instance...

                      Comment


                      • #12
                        I have ER 32 and ER 40 with #3 MT shanks that I use in the tailstock on the lathe and the spindle on the drill press. On the lathe, I can run up to 1" shank end mills for counterbores, large diam. drills, etc. On the drill press, anything over 5/8" goes in a collet.

                        For the OP - In your situation I would dial in the taper as you have shown and recut the entire taper with a carbide insert boring bar. Be sure to do lots of spring passes. That will remove the galling and make it run true.
                        Kansas City area

                        Comment


                        • #13
                          I have a similar set, they are DIN or OZ25. Collets for holding work have a through hole, collets for holding cutters have a disc screwed into the back which carries a centre point.
                          Dave

                          Comment


                          • #14
                            Originally posted by Euph0ny View Post
                            Well, you could put your collet holder with the MT3 shank in your tailstock, and use live tooling in the headstock, for instance...
                            Originally posted by Toolguy View Post
                            I have ER 32 and ER 40 with #3 MT shanks that I use in the tailstock on the lathe and the spindle on the drill press. On the lathe, I can run up to 1" shank end mills for counterbores, large diam. drills, etc. On the drill press, anything over 5/8" goes in a collet.

                            For the OP - In your situation I would dial in the taper as you have shown and recut the entire taper with a carbide insert boring bar. Be sure to do lots of spring passes. That will remove the galling and make it run true.
                            Got it

                            Advantage #3: tailstock chuck. Not having a drawbar for the tailstock, I can tap in one of these Vertex then use the collet nut on the front to clamp the work.

                            Advantage #4: they can hold larger diameters than MT3. Didn't think about that one.

                            Thanks for those.

                            Starting to seem a little more useful now

                            And, yes, I think I'm going to just recut the whole taper. But, first I'm going to cut a Weldon shank into a suitable slug of steel. If I'm going to go through the effort of dialing in that taper, I might as well use the same setting to cut my custom taper reamer too. Should be easy to toss a Weldon shank holder in the lathe spindle taper, mount the slug in it, and then cut the outside... oh... issue.

                            To use the same taper setting, I'll have to cut the backside of either the inside or outside on one... easy enough as my lathe reverses with a switch (to run in mill mode) and no threaded chucks etc.. I think I'll cut the front-inside of the holder, to match the carbide boring bars I have, and then the backside of the taper reamer. Have to check to see if the cross-slide has enough range first though. Might have to get creative with mounting the toolpost. Looks like I get a shop-day today too

                            David...
                            Last edited by fixerdave; 07-22-2016, 01:50 PM.
                            http://fixerdave.blogspot.com/

                            Comment


                            • #15
                              Originally posted by fixerdave View Post
                              .......I think I'm going to just recut the whole taper.......
                              Gary Paine gave you the best advice in Post #2.
                              Location: Saskatoon, Saskatchewan, Canada

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