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Which is better? (lathe 5C collet holders)

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  • Which is better? (lathe 5C collet holders)

    I have been using a draw bar that my father had made. The problem is it doesn't stay tight, due to the nylon collar. This was one of the last things he made.
    So I'm thinking of getting a 5C lathe chuck as shown. Just asking, what you would do, or which is better?
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  • #2
    Why trade rigidity or overhang ???
    If the drawtube is not staying tight,
    why not find the reason and fix the cause ?

    -D
    DZER

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    • #3
      I heartily agree with Doozer. I use a 5c Collet chuck on my Southbend 9 inch. Do not like the overhang. But it is a lot better than just using a 4 jaw. or 3 jaw. Regards David Powell

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      • #4
        Another vote for fixing the drawbar. I have had both drawbar setups and a chuck like pictured, the drawbar setup is far superior.

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        • #5
          Until recently I'd have also fallen squarely in the camp of fix the drawbar, but it might depend. I've heard that the chucks require many turns on the wrench to close the collet, and therefore the drawbar and spindle adapter is faster, and it is inherently more accurate and rigid.

          But another point came up in a recent thread that on large lathes with wide carriages you often cannot get the tool very close to the spindle nose without setting the compound perpendicular to the crossslide and hanging out out. My heavy 14x40 likely falls in this category but I've done minimal collet work on it thus far so can't really comment, but I can see it being true. This would be problematic especially for threading course threads where you want to use a 29deg compound angle vice direct infeed. In this case the collet chuck extends the work where it needs to be to "fit" the lathe, and these big lathes don't care about the extra stickout and are rigid enough for collet work as they are. The only trick then is that the chuck isn't so poorly made that it ruins the point of using collets.

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          • #6
            Originally posted by JCByrd24 View Post
            Until recently I'd have also fallen squarely in the camp of fix the drawbar, but it might depend. I've heard that the chucks require many turns on the wrench to close the collet, and therefore the drawbar and spindle adapter is faster, and it is inherently more accurate and rigid.

            But another point came up in a recent thread that on large lathes with wide carriages you often cannot get the tool very close to the spindle nose without setting the compound perpendicular to the crossslide and hanging out out. My heavy 14x40 likely falls in this category but I've done minimal collet work on it thus far so can't really comment, but I can see it being true. This would be problematic especially for threading course threads where you want to use a 29deg compound angle vice direct infeed. In this case the collet chuck extends the work where it needs to be to "fit" the lathe, and these big lathes don't care about the extra stickout and are rigid enough for collet work as they are. The only trick then is that the chuck isn't so poorly made that it ruins the point of using collets.
            ^this^

            If the machine is already set up with a draw-bar I would fix the issue with the collar. It could be as simple as swapping out the nylon for a steel collar and a little oil to keep it from galling. Seems kinda counter productive to have a piece of soft plastic as part of a device that needs to be rigid.

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            • #7
              Another vote for a new collar on the drawbar.

              My own drawbar setup has a similar draw tube. When I made it to fit my lathe I noticed that the outboard end of the spindle has a strong chamfer. So I set the pilot collar which on my draw tube is part of the handle so it has a matching taper. This makes it self centering in addition to perhaps somewhat self locking. But since it's a 45° I suspect that most of the lock is due to being more accurately centered. But the extra friction can't hurt.

              Perhaps your new collar needs to be something along that line? Check your own lathe's spindle to see what the shape of the end is and make the new collar so it matches really closely. Perhaps the size of the plastic collar isn't a good match that strongly self centers on your lathe? And that binds up the threading so you only think it's getting tight enough.

              With every lathe being so different from others my main source of surprise is that you were able to use a draw tube made by your father for his lathe. Or did the lathe come with the draw tube from your father? And if that's the case perhaps it's just a matter of the collar wearing and no longer fitting in a way that accurately centers the handwheel end of the tube?
              Chilliwack BC, Canada

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              • #8
                Originally posted by BCRider View Post

                With every lathe being so different from others my main source of surprise is that you were able to use a draw tube made by your father for his lathe. Or did the lathe come with the draw tube from your father? And if that's the case perhaps it's just a matter of the collar wearing and no longer fitting in a way that accurately centers the handwheel end of the tube?
                The whole draw bar was made by my father for this lathe. I have used this set-up a few times, and because the collar is nylon, I did not tighten very much, because I was afraid of striping the threads. The lathe is a 14 X 40 Enco lathe. He only had this lathe about a year before he died. My guess he was going to make a new collar out of steel but didn't get the chance. I wish he was alive to help me with this...

                Thanks for the info!!!

                Comment


                • #9
                  Originally posted by BCRider View Post
                  Another vote for a new collar on the drawbar.

                  My own drawbar setup has a similar draw tube. When I made it to fit my lathe I noticed that the outboard end of the spindle has a strong chamfer. So I set the pilot collar which on my draw tube is part of the handle so it has a matching taper. This makes it self centering in addition to perhaps somewhat self locking. But since it's a 45° I suspect that most of the lock is due to being more accurately centered. But the extra friction can't hurt.
                  I was going to point out pretty much the same thing. My lathe uses a very similar setup minus the threaded collar. The outboard end of the spindle is just a tube and the collar for the drawbar tube just has an angled nose that centers the whole thing in the spindle. Should not be difficult to duplicate. I or someone else could post some pictures if that would be helpful, but I suspect you get the idea.

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                  • #10
                    I have seen many collet drawtubes with a needle or ball thrust bearing just behind the handwheel
                    for eliminating friction.

                    -Doozer
                    DZER

                    Comment


                    • #11
                      I had a Clausing Metosa and a Nardini lathe. Neither one worked well with a 5C in the spindle. I couldn't get the carriage close enough to the headstock to do anything useful in a collet. I bought a spindle nose collet chuck. It is probably less accurate than a collet in the spindle but it puts the work out where I can reach it to machine it.

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                      • #12
                        As Doozer mentioned, needle thrust bearing.

                        Click image for larger version

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                        • #13
                          If your lathe has 5C native in the spindle, use it, no question.

                          If you need an inserted adaptor, it's still likely better, but not as certain, depends on how good the adapter is. If you make your own and mark it for same orientation as when made, it is nearly as good as native..

                          If the thing has a cam-loc and is super low stickout, and the carriage won't go there, well, you are stuck.

                          Your issue with loosening is maybe the plastic being a but "squeezy" and just relaxing the tension because of it. Anything rigid will be better. Brass, steel, even aluminum. Or a ball/roller thrust bearing.
                          2801 3147 6749 8779 4900 4900 4900

                          Keep eye on ball.
                          Hashim Khan


                          It's just a box of rain, I don't know who put it there.

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                          • #14
                            Tungsten Dipper. I would not worry too much about the thread of the draw tube or collets. In the picture below of my collet "chuck", draw tube and G wrench you may notice that the draw tube is narrow in the middle. That's because it's made from three pieces held together at the two joints with Loctite 680 in close fitting "finger tight" push fits. The G wrench is used to first seat and tighten the collet adapter onto the threaded nose of my lathe's spindle and then you may or may not see the holes in the draw tube wheel that I hook the G wrench into for tightening the collets. And while I don't bash on the wrench with anything but the heel of my hand it IS a roughly 12" long wrench. So things tighten up pretty nicely No damage to the threads in the cheezy piece of black pipe that the threaded nose end is made from or on the collets.

                            This has all shown me over about 3 dozen uses since I made the 5C setup about two years ago that a) Industrial adhesives for metal when used as directed are darn near as good as silver soldering and certainly as strong as low temp solder and b) it's hard to over tighten a 5C collet.

                            And in fact the issue you might have is simply not tightening them hard enough due to worrying about deforming the nylon collar. Go all gorilla on it and if the plastic is damaged then it's simply a sign that you need to make a new tougher sleeve.

                            If you don't want to take the draw bar apart consider the idea of making the new sleeve as two parts that you fit into the end of the spindle. If you make the new collar SLIGHTLY over size so the smaller OD does not quite fit into the end of the spindle you can then cut it in half and make it into a light press fit pair that won't fall out because the tube is in place. Yet when you pull out the tube the two halves get automatically "drifted" out of their pinched in place home in the spindle....

                            That make sense?

                            You might want to drill holes or cut slots and make a "G" wrench for the draw tube as well.

                            I know what you mean about your Pop. Mine is responsible for my early exposure to making things. It was a fine gift and as a young and mid aged adult on my part we shared many a shop story.

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                            Chilliwack BC, Canada

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                            • #15
                              if you prefer soldering over trusting adhesives (which are darn good these days), I found that with my 3C drawtube, I was able to use old time leaded plumber's solder with a reasonable overlap joint, and it has stood up to tightening pretty aggressively for a matter of 10+ years.

                              You do not necessarily need to use silver solder. The key is to have an overlap (mine was maybe 0.25") so that the solder is in shear, not direct tension. Silver solder will take tension, although it is even better in shear.

                              2801 3147 6749 8779 4900 4900 4900

                              Keep eye on ball.
                              Hashim Khan


                              It's just a box of rain, I don't know who put it there.

                              Comment

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