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  • Towing the Tailstock??

    I cobbled together the articles below and apologise for the poor quality.
    Is this a common practice, to tow the tailstock via the power feed to the Apron when drilling?
    There must be issues such as backing out to remove chips and would a smallish lathe tailstock track properly when not clamped down (if that makes sense)?



    These were quite separate articles some pages apart in the same book.

    Rgds
    Michael

    Australia

  • #2
    I've done this a few times when I had a lot of large-diameter holes to drill -- saved my wrists for sure. I used some strap-clamps for the purpose, though. It worked pretty well for me, but my lathe has dovetail ways so I was able to snug down the tailstock gibs to give a better fit on the ways. I wouldn't do it on a lathe with standard bedways for fear of the tailstock lifting up.

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    • #3
      I tried "towing the tailstock" once .... and only once. I can't remember how I tried it but the back of the tailstock lifted off the bed under power. The hold down bolt was just loose enough to slide by hand. Possibly the under side of the clamp plate twisted and jammed. I don't know but needless to say I won't do it again. This winters project is to build a dedicated drill holder for the carriage.
      TS

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      • #4
        I've done it a number of times on a Colchester. I tapped holes across the headstock side of the lower part of the tailstock casting to mount a bracket for coupling to the carriage.

        Slightly tighten the tailstock down to the bed ways enough before "towing" to avoid lifting.

        It's a pain to setup, peck drilling isn't very practical. Use a drill suited to deep hole drilling without pecking.

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        • #5
          It's very common on large lathes that have the tailstock mass.
          Some like Dean Smith and Grace even made 'towing eyes' built into the carriage to do just this.

          I can see where on a lighter machine lift could be a problem but the odd time I have done it on 5" / 6" centre hight sized lathes it's been OK provided you pilot drill first.

          .
          .

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



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          • #6
            Double Post
            Last edited by Forrest Addy; 10-12-2006, 05:29 AM.

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            • #7
              Most engine plathe carriages aren't built for drilling thrust so for running larger sized drills it would be wise to pre-drill about the websize.

              Towing the tailstock isn't a big deal. So long as your towing link has a shear pin intended to fail above a certain point the lathe's feed mechanism will be protected. As for tailstick lift, run it with the clamp just snug enough to keep the lift inder control. You might have to build a goody that holds the clamp lever it in position to keep the clearance just right.
              Last edited by Forrest Addy; 10-12-2006, 05:30 AM.

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              • #8
                Originally posted by John Stevenson
                It's very common on large lathes that have the tailstock mass.
                Some like Dean Smith and Grace even made 'towing eyes' built into the carriage to do just this.

                .
                Many DSGs also had a 'power drilling attachment', which is basically a solidly made bracket with MT socket, which bolts to the cross slide behing the compound.

                Tim

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                • #9
                  good morning.

                  this is a topical subject for me. i just finished a toolholder that holds a 3MT sleeve that is 1-1/2" in diameter. i had tried towing my tailstock and wasn't happy with that arrangement. the taper sleeve is pressed in the block and also held with some setscrews that go into dimples drilled in the sleeve. i would have bored the taper but i don't own a boring bar small enough to do that. also, this sleeve has a good female taper and a 1-1/2" straight hole is a lot easier to bore. to add to that, the slot in the sleeve sticks out the back of the toolholder to make it easy to get the chuck arbor out with a wedge.

                  the toolholder is sized to fit a regular bxa quick change toolpost. generic chinese piston type that seems to be fairly accurate and repeatable. all of this goes on a 14 x 40 lathe, also generic chinese, but it was the demonstrater model and had been worked over some when i got it. for he price it is a pretty good lathe.

                  <billr waits for all the flames from the china haters>

                  with that said, i am looking for a cincinnati traytop, and if/when i find one, i will give this lathe to my kid who wants to be a machinist. i have turned out lots of good parts on it and a few not so good, but i think that was more my fault than the machine's. i did have to replace the spindle bearings [warranty] and have had to replace a lot of the little ball oilers.

                  another subject: little ball oilers: i have spent 5 years looking for a good way to oil these beasts. i have modified several pump oil cans, but was still not happy. the eventual solution was to modify a grease gun to *hold* and pump oil. i put a rubber gasket in the end where the t-bar was and enough scrap round bar and flat washers to hold it in place. this thing will pump some oil. i feel much better now that i can flush the coolant and crap out from under my cross slide.

                  beware, however, because the grease gun puts out some serious pressure and i have blown the springs out of a couple of chinese ball oilers. the ones that the gits company has are better anyway, but are 1/4" as opposed to whatever metric size was on there. i had to ream and counterbore the holes a little to make them fit. if you do this, plug the bottom of the hole with some paper towel or something and make sure that there isn't any oil, etc. present to trap cast iron dust. what i do is plug he hole, drill/counterbore, and then vacuum it all out of the hole. then spray with good old wal mart carburetor cleaner and wipe/vacuum again. so far this has worked out pretty well.

                  your mileage may vary.

                  i do have some pictures of all of his, but i don't have any way to post them and i refuse to do photobucket. however, if you are interested, email me <[email protected]> and i will send them to you in the email. it ain't like any of it is any big trick and if i can figure it out, i am sure you can. there is an article about grease gun oilers at the dropbox.

                  happy thursday.

                  peace.
                  billr.
                  ........i dremel. therefore i am..........................

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                  • #10
                    A couple of links for this subject here:

                    http://iwr.ru.ac.za/~iwdf/lathe/tailpow.html

                    http://www.torchmate.com/powrfeed.html

                    Peter

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                    • #11
                      Towing the Tailstock??

                      FWIW, the old Monarch 17" x 78", that was in the shop I worked in, was set up for doing this. The tailstock had a tapered pocket at the front of the base that corresponded to a spring loaded plunger, also with a tapered point, that you engaged on the back of the apron. I mainly used it to tow the heavy tailstock forward when I had to move it up close to the chuck. I did use it to drive drills when I wanted a consistant feed rate. It sure beat the hell out of cranking.
                      Jim (KB4IVH)

                      Only fools abuse their tools.

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                      • #12
                        While it works just fine its realy not what the machine was made to do, It puts wear on the tailstock . I ran a lathe that was used like that a long time till the drills and a center all hit about 1/8" low.

                        An old warner swayze turret lathe with power feed and rapid traverse on the tailstock is the ticket.

                        heres a pic of one drilling a 1.875" hole.

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                        • #13
                          tatoomike, I think that tailstock probably weighs more than my lathe!
                          Peter Neill, that second link you provided has a good tip about using two chucks to center drill.
                          Thanks everyone for contributing. It is an interesting topic that I had not seen discussed before.

                          Rgds
                          Michael

                          Australia

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                          • #14
                            Its a good idea in Industry and works quite well
                            we had our Dean Smith Grace (40 HP) pulling 3 1/2 inch spade drills through 1040 and 4140 forgings.

                            I am reluctant HOWEVER to do it in my home shop.(Boxford ala SB)
                            If your lathe has a power feed shaft (hex or square) for carriage travel , like industrial lathes, then go for it.
                            If you only have a leadscrew, it's a bad idea, because of the severe amount of wear you are inducing in the screw. It's not made for the power you may need, and a good thread form is more important than a tired arm.
                            I guess you could tickle the clutch to handle it ,but wear is wear.

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