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Possible use for ER collets?

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  • Possible use for ER collets?

    The recent thread on the drill grinding article, and the things brought up in reply, made me think some more.

    The big issue with collet drill holders is the need for a half billion different ones. Most collets are only able to handle closely sized parts.

    But the ER collet is supposed to handle a relatively large range, and would potentially be ideal for this use. They are accurate enough in centering, readily available, and easy to use ( I presume).

    The big problem is the total lack of a thru hole in the holders. That might be fixable by modifying the holder.

    But as a drill holder for sharpening, it seems they should be very good. They might even hold over the flutes acceptably.

    That would eliminate the need for the V-notch, and toggle clamping, etc, as shown in the article. A simple alinement jig such as the one illustrated in the article, and a two-sided holder base would allow essentially the same type operation, with the improvement that there COULD be a stop used, since positioning would be totally consistent.
    1601

    Keep eye on ball.
    Hashim Khan

  • #2
    Originally posted by J Tiers
    The big problem is the total lack of a thru hole in the holders. That might be fixable by modifying the holder.
    That's not a universal problem, many ER holder have holes through the shank.

    Comment


    • #3
      There is all ready one on the market . Uses 7 collets to hold from .060- 1/2 inches. Most ER holders have a thru hole.
      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


      • #4
        Originally posted by lane
        There is all ready one on the market . Uses 7 collets to hold from .060- 1/2 inches. Most ER holders have a thru hole.
        Heck, there are already drill sharpeners on the market also..........

        Not long ago, the chorus was "ER holders have no usable thru hole".

        Now the chorus is "whatcha mean? Thay ALL have thru holes.......

        Go figure.........
        1601

        Keep eye on ball.
        Hashim Khan

        Comment


        • #5
          I like the ER collets and am in the process of making a holder for my Unimat and ER-11s. Also, I see no basic reason why there can not be a through hole. In the case of my design, it would almost be harder to block the back.

          I also read the article and have been thinking about drill sharpening. And this is not the first time the subject has crossed my mind. I WILL build or buy a sharpening machine. Soon I hope.

          I do see one additional drawback to using the ERs and that is cost. A good set of ER-11s cost me almost $150 and they only go to a bit over 1/4". I don't know if I can justify several hundred dollars for a larger sized set that may not get me much past 1/2". And that's just the collets, not the holder or any of the rest of the sharpening machine.

          I had a thought this afternoon. Instead of a collet or a single Vee holder, what about a series of interleafed Vee shaped fingers. You could make a bunch (12-20) of rectangles about 1" X 1.25" X 1/8" or even thinner. Then stack them and simultaneously cut a Vee shapped notch on one of the 1" edges, corner to corner on all of them at once. It would be big enough to hold up to a 1" drill and, with care in cutting the Vee, there is no lower limit to the size. You would also need an equal number of spacers about 0.5" X 1" X 1/8"+. The 1/8"+ would be 0.128" or so for clearance.

          Now divide them in half and use each half to make two sides by stacking Vees and spacers alternatively. For maximum accuracy, you would keep the Vee pieces in the same orientation as when they were cut (in a stack). One stack would start with a Vee piece and the other with a spacer. Tie the stacks together with cap screws while a piece of drill rod is used to align the Vees. Now rotate one stack 180 deg so the Vee ends of the two stacks intermesh. Any errors made while cutting the Vees will be symetric and will cancel out so when the two are closed together with a drill in the central square shaped opening, the drill will stay very well centered both vertically and horizontally in the pair.

          You need a box shaped frame aroung them with adjusting screws on both sides to close these Vee jaws. I would think 3/8" or 1/2" flat ground stock.

          This holder should be able to hold drills from #60 or less to 1" or more. They would be automatically centered vertically and an optical jig could be used to allow you to center horizontally by flipping the holder over and comparing the location in each orientation. Tighten the screws on each side like centering in a four jaw chuck, but easier as you only need to center in one direction. This holder will also provide the 180 degree indexing for sharpening the two flutes by simply flipping it over.

          That's as far as I have gotten with this idea. So far anyway. I need to buy/make a diamond wheel grinder to use with it. And some accurate way of positioning the holder to make split point drills.
          Paul A.

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

          Comment


          • #6
            I have been pushing ER collets for years, hence the spin indexer with combined 5C and ER capabilities,



            An adaptor from 5C to ER32,



            and the test X3 mill that has ER32 direct into the spindle.





            As far as I recall it's only JT who keeps saying ER's have no thru hole in the holders.

            Paul, It's possible to buy small ER11 chucks and a set of good collets for far less than that if you look around.

            I have about 3 of these sets in the workshop, one is fitted with a thread at one end so it can be held in a threaded Clarkson chuck, one has a keyway machined down the side and is held in a bushed and spring loaded spindle for engraving and one is just held in a 16mm collet for small cutter work.

            .
            .

            Sir John , Earl of Bligeport & Sudspumpwater. MBE [ Motor Bike Engineer ] Nottingham England.



            Comment


            • #7
              I really like ER collets. They work great in my mill and lathe. And the ER collet chucks are pretty easy to make as well. I made this thru-hole, screw on ER32 chuck for my lathe.



              Steve

              Comment


              • #8
                As far as I recall it's only JT who keeps saying ER's have no thru hole in the holders.
                I am not sufficiently motivated to "prove I am right" to go and search out prior posts..... I seem to recall others TELLING ME that there was no hole, when I asked (note I asked, and did not declare).

                I look in the catalogs, and I see ER holders on R8, straight shanks, or whatever, and they seem to obviously have no thru hole. At least if they do it don't come out the back...... so it seems to be true, at least in the US.

                But the US is resistant to the dictates of our old imperial masters in europe, so maybe we get bad "punishment" ER holders, just like only the most horrible "punishment" clunky metric screws etc also.....

                I am simply parroting what I was told by folks right here about ER, so if that is wrong, somebody better look in the mirror for the problem....

                The expense for ER is certainly a lot. A set of Jacobs rubberflex and a holder might be fewer collets and a wider range. But I always see the huge handwheel Jacobs holder, was there a smaller one also?
                Last edited by J Tiers; 09-15-2007, 12:04 PM.
                1601

                Keep eye on ball.
                Hashim Khan

                Comment


                • #9
                  Originally posted by J Tiers
                  IThe expense for ER is certainly a lot. A set of Jacobs rubberflex and a holder might be fewer collets and a wider range. But I always see the huge handwheel Jacobs holder, was there a smaller one also?
                  Here is an older rubber flex collet holder that uses a key like a jacobs chuck to tighten. I like it a lot.
                  Jonathan P.

                  Comment


                  • #10
                    ER collets

                    I have been at the HSM game for a couple of years now - first a lathe and now a Nichols horizontal mill with a vertical head based on 40 tapers. I owe my start to a life long machinist and model builder Reg Miller, thanks Reg!

                    Once I had the mill at home I did a fair bit of head scratching to figure out how I was going to hold tools in this mill. In the end I went with an ER40 system because it is good up to
                    1" and it was robust. I went the Chinese route for these collets and holder because it was affordable - I have no regrets...

                    I recently refitted a woodworking shaper that was built to accomodate 3/4" cutters only. I made a new spindle for the machine using an ER40 collet system - one trick pony! Now with three collets my shaper can use router bits and shaper cutters. My time is worth - well - nothing as all my friends with "small interesting jobs" tell me so I was able to get this shaper up with greater capacity for less than $200 in materials.

                    I recently bough a 5C kit with spin indexer etc. and am going to build the Loop collet chuck for my lathe.

                    Imagine my horror when I looked at the ER lathe chucks on this thread - why hadn't I thought of that? What a simple and elegant tool solution. Oh well I guess that you can't have too many collets. I will go metric on the lathe with the 5C collets because they are less expensive.



                    Last edited by chrisfournier; 09-15-2007, 02:04 PM.

                    Comment


                    • #11
                      Actually, the ER holder I use on my Bridgy doesn't have a through hole.

                      The holder itself was a cheapie bought from J&L a couple of years back to go with a nice set of german made ER collets I got.
                      Maybe it's just the 'budget' ones that don't have a hole through?

                      Either way it's a very good system, it's made my drill chuck redundant, and I hardly ever user the standard R8 anymore unless I need the extra headroom under the spindle.

                      Peter

                      Comment


                      • #12
                        ER collets have a lot to like. Through holes are the responsibility of the adapter, not the collet, and the front closing means no through hole space comandeered by a drawbar. They're straightforward to adapt for - one tapered cavity and one external thread. I usually do ER-32 adapters for Atlas threaded spindles (and M39 x 4.0), but it could be ER-40 if preferred, and the larger body allows it to be adapted to larger spindle threads too.

                        What could be easier than this.

                        .
                        "People will occasionally stumble over the truth, but most of the time they will pick themselves up and carry on" : Winston Churchill

                        Comment


                        • #13
                          Originally posted by John Stevenson
                          I have about 3 of these sets in the workshop, one is fitted with a thread at one end so it can be held in a threaded Clarkson chuck, one has a keyway machined down the side and is held in a bushed and spring loaded spindle for engraving and one is just held in a 16mm collet for small cutter work.

                          .
                          Is that a shop-made adapter or is it available for purchase? Odd this should come up as I'm on my way to Boeing surplus to look for some kind of spin indexer and or collets and carbide chips. I have several pending projects that require indexing and now that I'm unemployed I have time play in the shop.

                          Comment


                          • #14
                            I think John 'invented' that adaptor, and it's now commercialised over here via Arc Euro Trade:
                            http://www.arceurotrade.co.uk/

                            Click on 'latest' and scroll down a bit.

                            Peter

                            Comment


                            • #15
                              Sir John said,

                              "Paul, It's possible to buy small ER11 chucks and a set of good collets for far less than that if you look around."

                              Yes, I did look around. And there are ER11 sets for under $100. But I didn't want to go completely cheap and regreat it later. Hopefully it is a once in a lifetime purchase.

                              As for the through hole thing, I highly doubt that there is anything preventing a hole from being drilled in almost any of the collet holders or adapters except the hardness of the steel. Come on guys, we aren't helpless. Break out those carbide drills or boring bars and remedy that situation. As I said above, in the holder I am making it is almost harder to block the center hole than to have it.
                              Paul A.

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

                              Comment

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