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  • #31
    Good timing on this post as I'm just getting ready to buy a new TS arbor for an Allbrecht chuck someone just "gifted" me. since it was free, I should probably opt for a better quality arbor. Jacobs or Bison. My Bison 5' inch 3 jaw chuck is the only one of the three I've bought that spin true right out of the box.
    Robert
    grumpy old fart
    www.wirewerkes.com

    Comment


    • #32
      The justification for complaint is questionable since the actual dimensions of the taper blanks is not known. It is assumed they are wrong because they are made in India. It is assumed the tailstock is right because it was reamed with a reamer that is assumed to be correct because it was made by Morse. It is assumed the live center used to check the TS was right because it was made in Poland. That is a lot of assuming, why can it not also be assumed they are all within specification.

      Unless actual dimensions assigned, whether they are in tolerance or not will never be known.

      Without knowing the intended application, whether a problem exists or not also cannot be determined. Since the original design of the MT shank was for drilling, pressure of the drilling operation will tend to make it tighter in the socket. In that instance, the adaptors will probably work if they are within tolerance.

      The MT was not designed to handle side forces or pullout forces. If the application will be subject to these forces a different arrangement should be considered. MT arbors subject to these forces are threaded for drawbars.
      Jim H.

      Comment


      • #33
        Originally posted by wirewrkr
        ,I should probably opt for a better quality arbor. Jacobs or Bison.
        I've had good luck with Bison, but be careful with Jacobs -- they were bought out by the Danaher group years ago, and a lot of their stuff is now made in China.

        I have several Collis abors, adapters, and although they're expensive, they're exceptionally well-made.
        "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

        Comment


        • #34
          Originally posted by J Tiers
          BTW... What was that thing about a "tang drive"???? Means what?
          It's the fat little blade or tang on the arbor end of a MT drill or adapter that fits the corresponding slot in the quill that keeps it from turning/slipping in the taper when under a high torque load that the fit of the taper can't hold by it self.
          Most smaller lathes don't have this feature,usually MT3 and up have it .

          Comment


          • #35
            Originally posted by J.Ramsey
            It's the fat little blade or tang on the arbor end of a MT drill or adapter that fits the corresponding slot in the quill that keeps it from turning/slipping in the taper when under a high torque load that the fit of the taper can't hold by it self.
            Most smaller lathes don't have this feature,usually MT3 and up have it .
            Odd, If THAT was all you meant...... they already have the "removal tang" on them. As far as that being a "driving tang", well the ones I've seen twisted off didn't drive very well. The friction of a taper socket drives very well indeed, I doubt the tang adds anything, and I have heard the "driving tang" theory disputed by persons such as Forrest A.

            That is a lot of assuming, why can it not also be assumed they are all within specification.
            The evidence is that they appear to be "out", but they might possibly be just at the limit.... As for the reamer and center.... If three things are INTENDED to be made to fit into identical recesses tightly, and TWO of them precisely fit a particular recess, the simplest "assumption" is that both are very closely correct, and the odd one out is wrong.
            Otherwise, you have to assume that the two totally independently made items that fit well are both "off" to the precisely identical amount.......and I suggest THAT is a LOT of assumption.

            The MT was not designed to handle side forces or pullout forces. If the application will be subject to these forces a different arrangement should be considered. MT arbors subject to these forces are threaded for drawbars.
            I didn't just hatch this morning........ I do know that. The amount of side force or end force I expect is the same that a drill would experience. And that can be substantial, due to chips, but drills don't have drawbars.

            A good fit of taper ejects with somewhat of a "pop", it does not just "flop" out of the taper. Therefore it can withstand some end force, but clearly not a lot, a drawbar is required to resist substantial pulls, or milling. But a Morse is not a "self-ejecting" taper, rather it is more-or-less a "self-locking" taper.

            And, it is a rare tail-stock which has provision for a draw-bar, although I understand they do exist.
            Last edited by J Tiers; 02-08-2008, 11:33 PM.
            4357 2773 5150 9120 9135 8645 1007 1190 2133 9120 5942

            Keep eye on ball.
            Hashim Khan

            Everything not impossible is compulsory

            "There's no pleasing these serpents"......Lewis Carroll

            Comment


            • #36
              JT
              You sound like some people I know that even though they're not always right they're never wrong.
              Who's Forrest A. ? Did he design the Morse taper?
              If the tang is for removal then why the 2 flats?
              I have Greenfield 3-1/4 # 5 Morse taper drill bit that gets used often in an old 32" Hamilton lathe and I seriously doubt the taper alone would hold it even if I drove it in the tailstock quill with a 20 lb. sledge hammer.
              I'm sure you own a drill press?
              Knock out the Morse taper arbor an then try to reinstall it with the tang 90 degrees to the key removal slot ................ bet it won't fit.
              Better yet saw off your so called removal tang and see how long till it slips and falls out of the quill.
              I think you would complain to the hangman even if he used a new rope.

              Comment


              • #37
                Forrest Addy is a guy who has been in the biz for a long time and probably knows more about machine work than both of us put together.

                He is also the guy who does the scraping seminars that were organized by folks over on PM.... And the professionals over there respect his opinion a lot. I share that opinion of him. He has written a number of excellent articles for the magazine that sponsors this very site.

                In any case, I have a drill or so with bad (missing) tang, and they seem to drill just as well as any other, don't slip, but I DO have to tap them in solidly.

                if you have ever had to get a morse taper collet out after it's been rammed in well by holding work or a tool, you'd agree with the 'self-locking" description.

                And, I notice that drills which have been "pressured through" the work definitely come out with a "pop". There is a REASON why those wedges have to be tapped on smartly to get the drill out of the spindle.

                Of course it won't even go into the socket at 90 deg, unless it is one of the ones that were made with a round "nub" and not a tang. Yes there were some, no doubt to stop folks depending on the tang for driving......... I think I have one somewhere.

                "One of those guys who is never wrong"?

                That's a good, workable, insult, (and also an "ad hominem abusive" argument, btw) intended to end an argument on a "winning note" for the accuser, but t'aint so.

                I was wrong once in 1987, and I don't mind admitting it. So there!
                Last edited by J Tiers; 02-09-2008, 01:36 AM.
                4357 2773 5150 9120 9135 8645 1007 1190 2133 9120 5942

                Keep eye on ball.
                Hashim Khan

                Everything not impossible is compulsory

                "There's no pleasing these serpents"......Lewis Carroll

                Comment


                • #38
                  I guess that was you and Forrest driving the turnip truck I fell out of but I didn't realize that back in 1987.

                  You know you've spent more time talking/typing about your taper problem then it should have taken to fix it in the first place.

                  Professional?
                  Most machinist I know consider themselves tradesmen/craftsmen unless they have a chip on their shoulder.
                  Last edited by ; 02-09-2008, 03:21 AM. Reason: spelign

                  Comment


                  • #39
                    Regardless of what you assume, without numbers, all you know is that you have some taper shanks that are different. Reaming of the tailstock is not a precise operation, reamers will follow an out of line hole, and if not precisely in line, a taper reamer can produce a hole that is large on the small end.

                    Forrest is a great guy, but subject as subject to presenting opinion as fact as anyone else. I have a 1972 Bendix Tools catalog that defines tang as " The flattened end of a taper shank, intended to fit into a driving slot in a socket.

                    Armstrong, Williams and probably others manufactured taper shank sleeves with handles to be used in lathe tailstocks to keep taper shank tooling from slipping in a tailstock not equipped with a driving slot.
                    Jim H.

                    Comment


                    • #40
                      Originally posted by Milacron of PM
                      1. A yacht is a poor analogy to what we are talking about here....

                      2. I doubt anyone here is assuming cheap always means "bad" and expensive always means "good" ...
                      Granted, wasnt the best analogy, but is what came to mind, that and what i guess i didnt make clear was i was refering to some of the more critical subsystems that are made to similar spec limits to MT tapers, including some components critical to operation.

                      its not so much that they have failed "yet" its more that on some of the parts ive worked on are produciton parts used on almost all of the yachts made by the shipyard that made this one (which is since operating under a different name by a different company) most of the problems come down to the hydraulic systems where even the spares supplied from the original company were out of spec, and they were £280 spares for something around about the size of a cellphone. the yacht is far from new and the out of spec parts have lasted and have been fine for the intended use but if their had been a faliure at sea then the spares wouldnt have fitted and would have left the yacht stranded.

                      But enough of that as i said i didnt want to argue anyway my point was more along the lines of while most of the time you do get what you pay for and was pretty much agreeing with you and JT and lazlo.

                      But my main thought is/was sometimes albeit rarely you do get bad products from both ends of the expense scale and that if something is sold as an item that would normally be universaly expected to be within limits then i would expect even a cheap tool/taper to be within said limits regardless of price or origin. I've had bad sandvik tapers and bad cheap ones both of which were replaced for accurate stock.

                      With that said im also guilty of buying the cheap option if its not going to get much use.

                      I suppose its possible they had fill in workers or a trainee that day on QM so the bad tapers slipped through, which is pretty much what happend with my sandvik stuff which they replaced with absolutly no trouble at all.

                      Comment


                      • #41
                        Originally posted by J.Ramsey
                        It's the fat little blade or tang on the arbor end of a MT drill or adapter that fits the corresponding slot in the quill that keeps it from turning/slipping in the taper when under a high torque load that the fit of the taper can't hold by it self.
                        My Clausing tailstock (MT3) has the driving slot to keep the taper from spinning. The Monarch's do as well.
                        "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

                        Comment


                        • #42
                          Originally posted by J.Ramsey
                          You know you've spent more time talking/typing about your taper problem then it should have taken to fix it in the first place.
                          Ironic statement considering YOU are a major contributor to JT's "excess" talking/typing.

                          Amazes me when that happens on forums....the original poster gets the answers he needs in the first two or three responses and it would end there. But then other folks keep chattering away, often with total irrelevant BS of speculation or that accuses the poster of this or that. So the poster continues on just to clarify matters or defend himself from the BS.

                          And then the very BS perpetrator that contributed to the poster having to type unnecessarily more, is the very one who then makes fun of the poster for spending too much time typing about it !

                          Comment


                          • #43
                            Considering that "fixing it" involves tools I do not actually own (universal grinder, mine is incomplete) and do not have handy access to, don't know about "less time to fix". I might get it done in a week or two if I make arrangements. If I had to I could get it faster.

                            Are they out of spec?

                            I DO NOT GIVE A RAT'S TUSCHIE IF THEY ARE OUT OF SPEC OR IN SPEC.

                            They do not fit well enough to work for the application, and yes indeedy, they DO "FLOP OUT" of the taper, when a large selection of other taper shank tools STAY IN and come out with a "pop".

                            1) Specs are written originally by the developer of the "device", and "groomed" by industry folks who don't want extra production trouble. 0.002 per foot probably makes a nearly unusable fit if BOTH the taper and the tool are at maximum error. That would be 0.004 per foot loose, and the taper might well not hold. But it surely makes it easy to make..... with tools per 1870 or so.

                            2) Very odd that my "must be out of spec and obviously isn't accurate because it is reamed and not ground" taper just HAPPENS to FIT a wide variety of tools that were made at different times by different folks and therefore have totally uncorrelated errors.

                            It is obviously technically not "impossible" that all my other MT2 shank tools AND the reamer are miles out of spec in the same direction. But it isn't very likely.

                            Do I KNOW what the actual error of the tapers is? NOPE...... and I never have claimed to *KNOW*.

                            For all I know, that is what a "limit spec" MT is like. I'll have to measure their taper, that does not require any gage-line info, just a slope. Sounds like a pain.

                            What I know is that these three, from a suspect source, are DIFFERENT from that "boxload" of ones made by generally respected companies like Morse, Cleveland T & D, Jacobs (old Jacobs) etc, and even Bison brand. I also know these three are different enough to be unusable in general.

                            Given that, apparently the ONLY possible assumption is that these three are the ONLY ones of the lot that are "in spec"...... YUP, that's what anyone would deduce from the info at hand. Uh HUH....!

                            Heck, the original point was that these things are so well finished, and nice looking, you'd a thunk the makers would have bothered to get the taper close enough to work right.

                            BTW, I type fairly fast, so no need to feel I am wasting time.......
                            Last edited by J Tiers; 02-09-2008, 11:09 AM.
                            4357 2773 5150 9120 9135 8645 1007 1190 2133 9120 5942

                            Keep eye on ball.
                            Hashim Khan

                            Everything not impossible is compulsory

                            "There's no pleasing these serpents"......Lewis Carroll

                            Comment


                            • #44
                              Knock out the Morse taper arbor an then try to reinstall it with the tang 90 degrees to the key removal slot ................ bet it won't fit.
                              Better yet saw off your so called removal tang and see how long till it slips and falls out of the quill.
                              The tang is for removal. It's not hardened and will twist if allowed to take torque loads because of a poor fit of the taper in the socket. The reason it is made as a flat tang is to prevent spinning of the taper in case of looseness so that the spindle isn't damaged by such spinning, not to provide drive. It's a safety feature as well as a removal feature. It's better to damage the drill bit than the spindle.

                              The tailstock and headstock on my South bend have no provision for trapping the tang and yet have no trouble drilling 1" holes in steel. I have perhaps 25 or so MT2 and MT3 drill bits. They are either US or UK made and never slip unless I haven't cleaned something properly.
                              Free software for calculating bolt circles and similar: Click Here

                              Comment


                              • #45
                                OK, they ARE out of spec.............

                                Large end = 0.7148

                                small end = 0.5764

                                distance along taper slope is 2.741"

                                Doing the appropriate trig to get the actual length on axis, and figurung out teh taper, I get an actual taper per foot of 0.6066.

                                The spec taper is 0.5994

                                That would appear to put these at nearly 3 X the tolerance out of spec
                                4357 2773 5150 9120 9135 8645 1007 1190 2133 9120 5942

                                Keep eye on ball.
                                Hashim Khan

                                Everything not impossible is compulsory

                                "There's no pleasing these serpents"......Lewis Carroll

                                Comment

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