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  • #16
    Btw dockrat, Why do you need a center on such short parts?
    Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.

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    • #17
      Tailstocks do not have rams, unless they are also shepherds and have a male sheep. They have quills. The quill need not reach all of the way over the apron as short workpieces do not usually need its support. This inability is of course a hallmark of a cheap machine, as you must be aware since you probably bought it for that reason.. So what's to complain about?
      Last edited by tdmidget; 11-07-2009, 11:27 PM.

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      • #18
        Originally posted by Black_Moons
        Btw dockrat, Why do you need a center on such short parts?
        No, that was just posed to show how short the "quill" is trying to reach over the table. When I am using it with a long piece of stock I can reach the stock but can't get the carriage back far enough to start a cut without it hitting the tailstock hence the extention. Take another look at the second pic in the OP. The tailstock is up against the carriage and the ram is fully extended. Look where the cutting tool is. I could roll the compound back to start the cut but that then puts the front of the carriage in jeapardy of getting hit by the chuck if I am turning a larger piece of stock. Ask me how I know.
        Last edited by dockrat; 11-08-2009, 12:36 AM.
        Ernie (VE7ERN)

        May the wind be always at your back

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        • #19
          Originally posted by dockrat
          No, that was just posed to show how short the "quill" is trying to reach over the table. When I am using it with a long piece of stock I can reach the stock but can't get the carriage back far enough to start a cut without it hitting the tailstock hence the extention.
          I have the same problem and is why I didn't use a center when turning this screw-making project: http://metalworkingathome.com/?p=40

          Just too crowded.

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          • #20
            Originally posted by tdmidget
            Tailstocks do not have rams, unless they are also shepherds and have a male sheep.
            Quill, barrel, and ram are common terms and I doubt anyone is confused.

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            • #21
              Pics - later

              I've taken a few pics of mine that might help.

              I will post them later - after I have edited and up-loaded them.

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              • #22
                Originally posted by Black_Moons
                ...Why do you need a center on such short parts?
                Originally posted by tdmidget
                ... The quill need not reach all of the way over the apron as short workpieces do not usually need its support... So what's to complain about?
                True perhaps, but clamping blank discs, drilling / tapping small jobs and faceplate work all ask you to reach a little further.

                .

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                • #23
                  This is a problem to some extent on most Lathes.

                  Someone (Dave Piddinton?) came up with the idea of an extended tool holder to fit the Dickson toolpost and you can now buy such a thing direct from Myford. Copies are also available like this T1 size holder from Chronos



                  It would seem to me that this is the most rigid (for the least work) solution for tailstick interference.
                  Paul Compton
                  www.morini-mania.co.uk
                  http://www.youtube.com/user/EVguru

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                  • #24
                    I'm ahead of my time.

                    Back in 2004 I mentioned something very similar: here I pondered making a shaper-ram style tailstock with a capstan wheel for drilling, here I asked about the possibility of fitting a sort of "gib" to the quill, and I mentioned both again here after replacing the handwheel screw in my Logan tailstock.

                    Since then I've revisited both ideas a couple of times, but only in passing. I'd still love to have a drill-press-quill style tailstock with a spider wheel rather than a handwheel.

                    I once even ran across a junked import drill press for cheap or free, and I recalled someone's post here where they sawed up a cheap import press to make a sort of toolpost grinder. I figured I could use the quill, handles and gear for the tailstock, but I hesitated and the guy threw it away.

                    And, one of the ideas I toyed with for the local art troupe to cast for me in iron was a new tailstock body- my Sheldon TS quill falls off the screw at exactly 2-1/2", with half an inch taken up by the tang of the tool, giving me an effective working range of two inches- really only about 1-3/4" to be sure it doesn't pop off the threads. More than a few times that just hasn't been enough.

                    One of these days I might even get around to trying one of 'em.

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

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                    • #25
                      People have skirted a simple idea...

                      A tailstock Quill,Ram, whatever..

                      Mounted in a set of 5C collets (for example) facing out from both ends of tailstock. One end (I would use outer, would have a simple closer wheel)

                      One of the 5C's would have reverse threads...

                      Outboard of that, is a thrust shoulder that can be involute splined for centering/antirotation effect, but still loose enough to allow the 5C's to center both ends... Square 5C's could be used for cheaper lathes

                      Would make for a longer tailstock top, but accuracy should be there...

                      Another handwheel used to run quill in and out...

                      Could even be CNC controlled...
                      With ram having no inner side key to let debris in, a seal could be used on inner side.

                      Worn ram/quill, either new ram or a regrind and new collets...
                      Back to my beer
                      Last edited by Bguns; 11-08-2009, 07:15 AM.

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                      • #26
                        Tailstock design Part 1

                        Could be long, get a coffee and may run into two posts because of the pictures.

                        Actually this is a pet peeve of mine beside the crap Bridgeport and I have done a lot of study on it.

                        First the traditional design has just been copied over and over again, see my other post on tailstock's but there have been alterations. One was the CAV [ not to be confused with the 10EE clone the CVA ]



                        A quite cheap in it's day lathe but it did address the issue.

                        Possibly one of the better thought out designs was the French Cazeneuve which has lever, hand wheel, fine feed and power feed.



                        A very modern design with little of the grandfathers rights design.

                        But to get back to the OP question. The problem lies in the fact that the body is short therefore the barrel is also short, add to that the internal crew arrangement that is designed to be self extracting gives a travel that is in proportion to the body length and can't be altered.

                        Two obvious ways this can be addressed, the easiest way is to turn the barrel arrangement from an internal screw to external screw.
                        Not new, Myford's did this to address the same issues on the ML7, in fact when they brought out the new Super 7 they had to fit a longer tailstock to get anywhere near the same travel which reduced the between centres distance of the lathe.



                        7" swing and 20" between centres, because it has no self extracting facility, the barrel is hollow and you use a brass knock out bar, but it has a far greater travel than if it had an internal screw. The handwheel is retained by a keep plate fitted into the large diameter casting on the handwheel end.

                        This handwheel can be removed and a simple lever feed fitted instead very easily.



                        No alterations have to be done to fit this, it's a pure bolt on solution. The clamp that bolts onto the barrel clamps directly to the top of the square threads for ease of manufacture.
                        These work very well and I used one for years.

                        Continued on post two due to the 4 picture limit.

                        .
                        Last edited by John Stevenson; 11-08-2009, 07:17 AM.
                        .

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



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                        • #27
                          Guess I have to add.. a lever and handwheel, would work for my idea also
                          For lever feed with handwheel adjustable friction control quill/ram lock...

                          Loosen 5C's, run feed wheel off, slide new lever quill/ram in..

                          With spline selfcentering, and wear adjustment built in..

                          Hollow center knock out if desired.. Or even a 3rd wheel for that ....

                          Not a cheap way to go.. But classy
                          Last edited by Bguns; 11-08-2009, 07:36 AM.

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                          • #28
                            Sorry - posted to wrong thread - deleted

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                            • #29
                              Tailstock Design part 2

                              When Myfords brought the Super 7 out [ S7 ] they tidied the design up and mage the tailstock similar to what was then the industry standard.



                              However this reduced the between centres distance by 1" not the extra length to carry the longer barrel and screw for the designed travel.

                              This body length / barrel length is critical if you use an internal screw.
                              They also offered a lever feed conversion.



                              However this was expensive as it needed a new longer barrel to achieve the same travel as the screw tailstock but unfortunately it didn't achieve this.

                              It is possible to get both lever feed and handwheel, AND retain the original barrel and screw IF you study the design correctly.



                              This is a S7 tailstock, ignore the coachwork as it's a working concept design and I'm not wasting money on new tailstocks.

                              Lever feed and handwheel using all the original components, no alterations to castings or any parts. Besides the lever components there is a barrel extension and a screw extension fitted internally, that is all.

                              Using just the lever feed the stroke is nearly 4", about 3/4" greater than the Myford lever design.



                              However the use of lever and fine feed via the handwheel can be used in any combination, just lever, just handwheel or handwheel in and quick retract with the lever to clear chips, in fact any combination you want.

                              New post.
                              .

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



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                              • #30
                                Nice upgrade John..

                                The Myford at least, had a decent length of tailstock bore...

                                Saw a lever that kinda looked like that recently, from some Canadian

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