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  • Turning problems

    Hey guys,

    I have a mastercraft 37Ē lathe, has it for a while now and it has produced a fair amount of projects for me.
    Recently I have been having an issue. Trying to make a French style rolling pin for a wedding gift using Indian rosewood.
    I mark my Centers after making sure the blank is square, then run it through the table saw on 45 to cut the corners off.
    It seems good at first then seems to lose centre on the tailstock end because it starts wobbling like crazy and the pin has a major warp to it that I cannot seem to get back.
    Ruined one blank this way and I thought I just was lazy and didnít properly square the blank, but the second one I took my time and squared it good, and started with true Center and it still did the same thing.
    Never had this problem before, is my lathe out of alignment or am I doing something wrong?

    Thanks

    Colin
  • Thread Continues Below...

  • #2

    Re: Turning problems

    One thing you could try is to slide your tail stock with your live center in it, up to the head stock with a spur drive in it and see if the points on each line up. If they don't, then the guide on the bottom of the tube is out of alignment.

    James

    Comment


    • #3

      Re: Turning problems

      It could be the point on the live centre is chewing it's way into the end grain. I use a cup live centre on spindle turning which helps it to stay on true centre. Check the alignment as James has mentioned first though.

      Comment


      • #4

        Re: Turning problems

        The alignment when brought to headstock is important but if the tube frame bends it is irrelevant.

        Comment


        • #5

          Re: Turning problems

          are you using a live centre or a dead centre, a live centre spins with the work piece and wont wear a hole in the end
          my shop is a beaver lodge
          steve, sarnia, ont




          1940's Craftmaster Lathe

          https://www.facebook.com/artistryinwoodca/

          Comment


          • #6

            Re: Turning problems

            I messed around last night with it.
            The tailstock was sliding a little rough so I got carried away scrubbing the bed down with some scotch brite then hit it with some bostik and now slides perfect.
            Brought the tailstock up to the headstock and it is out, but barely, weíre talking a 32nd out of that would that honestly need the cause of my problems??

            Anyways I took my second blank and figured the only twist in it was three inches on the end so I cut it off, re found Center again and tried to bring it back, I managed to get it working and completed the pin with no wobble. So hereís what Iím wondering, this rosewood is a lot harder then anything Iíve ever worked with, and everything needs to be extra tight otherwise the spur drive doesnít make contact and slips, so Iím wondering is it possible that Iím tightening too much that Iím putting a bow in the wood, or is pushing back on the tail stock so much that itís bowing out?

            Using a live centre by the way steve

            Colin

            Comment

            • Thread Continues Below...

            • #7

              Re: Turning problems

              If the stock is not too thin, and a rolling pin shouldn't be, or too long then I don't think it is bowing but it is something to be aware of.

              Before you mount the piece to the lathe, drill a tiny hole on the centre marks for the pins. For the spur centre drive end, you can cut grooves with a handsaw to match the spur's teeth and/or you can take the spur and drive it into the hard wood with a hammer off the lathe to make a good indentation of the teeth. If the piece isn't much bigger than the diameter of the spur there can be a cracking risk. Put a block of wood on top of the end of the spur so the hammer doesn't damage it or try a plastic hammer. Put it on the lathe and tighten it well and after a few minutes check the tightness again and adjust if necessary. Check this from time to time during the turning operation.

              billh

              Comment


              • #8

                Re: Turning problems

                i would certainly follow all the suggestions above, i always use bill's suggestion of drilling small holes and cutting grooves for the teeth

                on large spindle pieces, i very often do the roughing using a scroll chuck, salt and pepper sets for example. i do use a live centre in that situation as well. put your square blank in the scroll chuck and live centre, rough turn as much as posible, flip the blank around and finish roughing. then mount between centres for finish turning
                my shop is a beaver lodge
                steve, sarnia, ont




                1940's Craftmaster Lathe

                https://www.facebook.com/artistryinwoodca/

                Comment


                • #9

                  Re: Turning problems

                  Originally posted by Redbull1989 View Post
                  I messed around last night with it.
                  The tailstock was sliding a little rough so I got carried away scrubbing the bed down with some scotch brite then hit it with some bostik and now slides perfect.
                  Brought the tailstock up to the headstock and it is out, but barely, weíre talking a 32nd out of that would that honestly need the cause of my problems??

                  Anyways I took my second blank and figured the only twist in it was three inches on the end so I cut it off, re found Center again and tried to bring it back, I managed to get it working and completed the pin with no wobble. So hereís what Iím wondering, this rosewood is a lot harder then anything Iíve ever worked with, and everything needs to be extra tight otherwise the spur drive doesnít make contact and slips, so Iím wondering is it possible that Iím tightening too much that Iím putting a bow in the wood, or is pushing back on the tail stock so much that itís bowing out?

                  Using a live centre by the way steve

                  Colin
                  Colin, that the tailstock is off a little, or even a ľ” does not matter when turning a spindle on a wood lathe, yes it matters with a metal lathe where the tool is clamped rigidly and on a carriage that travels down the lathe bed, as it would make for tapered spindles.

                  With a wood lathe where we handhold a turning tool it does NOT matter that the tailstock is off some, except when we are turning a thinner disk where the tailstock center is right close to the headstock, where when the center is off, it will fight the lathe’s center,......................... so this being out of the way, next,

                  Your problem is this, Click image for larger version  Name:	Mastercraft lathe.jpg Views:	0 Size:	58.1 KB ID:	1256997 the cheaply made lathe.

                  If you read the lathes manual (You do have it ??), on page 4 or so it gives you this, Click image for larger version  Name:	Tailstock and live center.jpg Views:	0 Size:	46.2 KB ID:	1256998





                  and also this about spindle turning, Click image for larger version  Name:	spindle turning.jpg Views:	0 Size:	31.7 KB ID:	1256999

                  With the small disk in the tailstock that moves the tailstock ram, you are not able to get a good pressure of the live center into the spindle, plus the whole tailstock is not ridged and can easily move, also the fit of the ram was never very good, all of his together makes for difficult working on that lathe.

                  What I recommend here is that you go and get a “center drill bit”, and drill the center of the wood at the tailstock end of your spindle turning wood, this will have the live center sit much more solidly, and hold the wood much better.

                  Click image for larger version  Name:	center drill bit.jpg Views:	0 Size:	3.9 KB ID:	1257000

                  Last edited by Leo Van Der Loo; 10-29-2019, 09:02 PM.

                  Have fun and take care
                  Leo Van Der Loo

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