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  • follow rest project

    Ok, here's a bit more of a breakdown on this project. If I went back about a month or so, I'd be able to say why I 'needed' this- maybe I just needed another distraction in my life so got the gears churning yet again- At any rate, a few more images- first is a head-on view. I've re-mounted the lower ball bearing on the other side of the jaw to show how it will clear the vertical plate and allow the jaws to open fully.



    Looking at the left side again. The base mounts on my carriage, and the steel piece you see on it has been aligned using an indicator so it's precisely parallel to the spindle axis.



    Here's a parts layout. The jaw assemblies are epoxied together as you see them- the thick washer with the gear segments, the jaw, and the pin are one piece now. If I was to build this again, I would do the gear thing differently- what I would do is turn the gear on the lathe to make a ring out of it, then cut the segments out of the ring, then machine the jaw to accept the gear segment glued directly to the side of the jaw. Basically the gear segment would be part of the jaw and not sitting on top the jaw as you see it. It would have been less fooling around with alignment, hole drilling and tapping, etc, and the jaw profile would be lower. Some of you might be willing to cut the teeth directly into the jaw- the end requirement is that the jaws can swing equally and oppositely in lock-step. To this end, I left one gear/washer loose until the exact alignment was determined with the project mounted on the lathe, and a test diameter stub turned and left in the chuck as a reference.



    Last edited by darryl; 02-20-2010, 02:12 AM.
    I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

  • #2
    Continuing- I went to some considerable trouble to create the dovetailed 'foot' and the curved steel piece which connects it to the upright plate. The curve is just slightly larger than the biggest diameter of workpiece I can support with this rest. Those three parts were fitted into a jig for the epoxying step. You can probably see some of the roughness under the curved steel piece- some of that is epoxy that I couldn't reach to wipe away because of the jig. It's no matter- it doesn't get in the way of anything. I used PC-7, and I remain impressed with how well it mixes, wipes onto a surface, stays in place without running, and holds.



    This picture shows the details of the clamp at the rear- the base has been dovetailed at the back, and the pivoting clamp pulls it all tight. I've played with it a bit now, and it's sure nice to be able to position the follow rest behind the toolpost exactly where it suits.



    Were the gears really needed? I suppose you could adjust each jaw with bearing individually, and once tightened down the thing would do its job and that's that. One thing I wanted to be able to do is have this tool define where the outboard end of the workpiece sits, and not the workpiece control where the bearings are adjusted to. All about keeping the workpiece concentric with the spindle axis- . What I do now is run the carriage up close to the chuck, loosen the jaws and adjust them against the workpiece (which is hopefully well centered at the chuck end) then tighten the jaws. Then run the carriage over and know that when the workpiece is touching both bearings, it's right on axis. Still don't need the gears for that, granted. It does make it a bit nicer to adjust though, since the back jaw will always be where it should be if the top jaw is where it should be. If I don't take the extra step of adjusting the jaws near the chuck first, at least I can see whether or not it's running out- if one bearing touches and the other doesn't, I know the workpiece is not on axis.

    Referring back to a previous image, you see three small holes in the butterfly piece- as part of the alignment process, the lowest one was positioned on a stub turned true. This piece was then angled up the support plate to the 45 degree mark, then the horseshoe piece was aligned to that and mating marks made for it's mounting bolts. This way, the sliding butterfly piece could always remain aligned to the spindle axis. As I play with it, I find that I can open or close the jaws and both bearings touch the workpiece at the same time, regardless of its diameter. By sliding the assembly, I can control where on the workpiece the bearings touch- a bit low at the rear and a fit forward at the top seems to be a good way to set it.
    Last edited by darryl; 02-20-2010, 02:56 AM.
    I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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    • #3
      Looks sharp. How does it work?

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      • #4
        I've only used it a couple of times in testing, but it seems quite solid. It doesn't vibrate, and I did not have any problem with cuttings becoming trapped between the bearings and the workpiece. I'm sure that will happen sometime, though. I did see where the bearings are sensitive to the surface finish that runs up against them, not unexpectedly, and I can see the result of that in the turned finish. It seems that I'll continue to use a slightly forward position for the top jaw, and a matching slightly low position for the rear jaw. Seems to work well.

        As a follow rest it will work best with workpieces that are smooth and round. For the most part it will get used where the outer finish on the workpiece is to be left as is, with only a secondary operation being done to a part of it, like turning the diameter down for a short distance from the end- things like that.

        I'm anxious to see how well it will run on threads being cut- I might find that I'll have to debur between successive passes.
        I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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        • #5
          follow rest project

          I would like to know what size lathe you are using this beast on.
          A ruler in the pictures would put it in perspective.
          I have a Hardinge HLV-H clone (11" swing) and the business end of follow rest for that consists of a piece of 1" x .250" Brass with a Vee cut in it.
          After all, unless you have an oil field lathe then machining long rods that are more than an inch or so in diameter is unusual.
          In short I think your follow rest is overkill.

          Steve
          PS: I usually don't spend time on this forum, so reply to me directly.

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          • #6
            Don't you just hate it when someone comes on a forum and tells you what you should be doing, and then tells you to reply to them directly since they don't have the time to mess with looking back in? I do anyway.
            James

            P.S. Darryl, forgot to say that is a really sharp looking rest. Good Job
            Last edited by J. Randall; 04-01-2010, 01:49 AM.

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            • #7
              Originally posted by macnosy
              I would like to know what size lathe you are using this beast on.
              A ruler in the pictures would put it in perspective.
              I have a Hardinge HLV-H clone (11" swing) and the business end of follow rest for that consists of a piece of 1" x .250" Brass with a Vee cut in it.
              After all, unless you have an oil field lathe then machining long rods that are more than an inch or so in diameter is unusual.
              In short I think your follow rest is overkill.

              Steve
              PS: I usually don't spend time on this forum, so reply to me directly.

              And is there anything else you would like/order him to do? Maybe bring you coffee while he is taking his time to answer your question!!!!!!
              Location: The Black Forest in Germany

              How to become a millionaire: Start out with 10 million and take up machining as a hobby!

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              • #8
                Steve, if you don't spend much time on this forum, it's unlikely you'd get my reply anyway, so I'll just put a short note here- this was a complex and time consuming project, but I enjoyed figuring it out and building it. I posted it to show what I had been up to, and to possibly give others ideas for things to do in their own shops, and to show the pitfalls I ran into during the design and construction of it. I don't consider any of that a waste of time. It's a unique accessory that won't get much use (though I have used it a few times now) but it was mentally stimulating to figure out and fun to build. I personally don't feel that I wasted time on it, but that's not to say that anyone else would feel the same way. If anyone wanted to build something similar, they're certainly free to choose to, and I hope I've posted enough information to be useful to someone- even if only to dissuade them from building this time consuming project.

                Thanks J Randall for the kind comments. This has turned out to be one of the more interesting things I've built, and I have used it and will again. It seems to work well.

                By the way, my lathe is an 8 x 18 Advance.

                Oh, on the brass with a vee in it- that's a pretty simple and rugged support that applies the KISS principle- nothing wrong with that. In fact I was thinking of building an extension arm that would bolt to the back of the tailstock. This arm would support one or more notched pieces to support a workpiece. Would be a much simpler project, and probably uniquely useful in its own way.
                Last edited by darryl; 04-01-2010, 06:14 AM.
                I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                Comment


                • #9
                  Darryl, your build came out nice. Hope it works out for you. Wish I had the mental horsepower/patience to stay with a project that stumps me till I work through it but I don't.
                  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
                  Thank you to our families of soldiers, many of whom have given so much more then the rest of us for the Freedom we enjoy.

                  It is true, there is nothing free about freedom, don't be so quick to give it away.

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                  • #10
                    Nice job Darryl, very nice, time consuming and complex is easily seen and understood.

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                    • #11
                      Very nice Darryl!!! Thanks for sharing...

                      I posted it to show what I had been up to, and to possibly give others ideas for things to do in their own shops, and to show the pitfalls I ran into during the design and construction of it. I don't consider any of that a waste of time. It's a unique accessory that won't get much use (though I have used it a few times now) but it was mentally stimulating to figure out and fun to build. I personally don't feel that I wasted time on it, but that's not to say that anyone else would feel the same way.
                      Well put! And I share your feelings along this line -- I am currently doing the "cut knurler" by Mcguyver in HSM magazine and have been asked/told "why, youve already got 3-4 knurlers?" Well, like you said, it looked interesting, seemed to be a good challenge -- and--- I didnt have a project at the time

                      Why do we have to need a particular item we are working on - cant just the pleasure of using our tools and creating something be a good enough reason?
                      If everything seems to be going well, you have obviously overlooked something........

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                      • #12
                        Really nice, and looks great. I can see you have put a lot of hours into designing and building it.

                        Maybe that other fellow doesn't spend enough time here to understand us and our projects, His loss.
                        Davo

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                        • #13
                          When I first looked at the pics I thought to myself, "wow!"

                          Whether or not it's overkill I think it's the coolest follow rest I have ever seen!

                          Great job and design!

                          Steve

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                          • #14
                            Nice job on the follower rest! I think "overkill" can be a really good thing. I certainly enjoy looking at all those "overkill" model cars, engines, machines, and accessories that some people have the knowledge, skill, and patience to produce and I know it gave them a lot of pleasure to do it.
                            Don Young

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                            • #15
                              Gosh- I think maybe Steve posted what he said just so you guys would chime in and give me kudos on this thing. Thanks for all the kind words.
                              I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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