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  • PITA Sketchy setups

    You have to be real careful with milling on the lathe. I was going to use Paul's sub plate idea, but I couldn't get the proper height for my project. Let alone the fact that no way to clamp it realistically. The job is getting done anyway. The vise is bolted thru between the side rails with 1/2-13 into the dovetail plug in the cross slide. I still don't like the setup at all, taking *real* small bites, but it is working.
    Cutter is 3/8 carbide at 750 RPM in A36 mild steel. Saddle is locked for each pass, conventional cutting *only*

    Making a crotch center for drilling in the lathe, needs a vee all the way across the drill pad, centered. The hole is also 3/8 so that makes setup easy in that regard. But still a PITA.

    Any better ideas? What crazy setups have you had to do?

    Click image for larger version

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    25 miles north of Buffalo NY, USA

  • #2
    Well for that one I would grab a V like angle iron, make a ceter to fit said V on lathe. Make the round end, insert in tailstock , and try to tack in place on a lathe..your setup might slip.
    if you can mount an angle plate on your compound, drill a hole for your round end, then mount your piece .. you can mill with tool in chuck, and move work with cross slide.

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    • #3
      Yeah, but I'm trying to get away from anything that looks like an angle plate or a vertical slide -- not enough rigidity to try it. Well, I did try it and I though it was going to crack the cross slide. Believe it or not, this setup is actually the best one so far, but there has to be a better way.
      25 miles north of Buffalo NY, USA

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      • #4
        What is keeping the cylinder workpiece from tilting? Just friction? That's risky in my experience. Been there, learned that lesson the hard way.

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        • #5
          Originally posted by rklopp View Post
          What is keeping the cylinder workpiece from tilting? Just friction? That's risky in my experience. Been there, learned that lesson the hard way.
          Yeah just friction. I don't like it at all. I have Vee blocks, but all the setups I tried with them, would not put the part in the right place... what to do????
          25 miles north of Buffalo NY, USA

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          • #6
            Originally posted by nickel-city-fab View Post
            what to do????
            I would put something in to avoid the "steel on steel" situation. I've got a bag of these in the shop. Not sure what they are called in the US. They compress nicely, I have used them when milling roughly cut stock.

            Click image for larger version  Name:	reusable-bamboo-ice-block-popsicle-sticks-24.jpg Views:	0 Size:	21.8 KB ID:	1885428

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            • #7
              Paul of "Paul's sub plate" here. I have not used my lathe milling table for any angled cuts yet. And I do have a milling machine now and that would be my choice in making that cut.

              Seeing that cylindrical part gripped on two sides makes me shutter. The expected outcome, in my mind, is the part rotates on the second to last pass, ruining the part and breaking the milling cutter. And of course, my wife would enter the shop at that point and strongly admonish me for my choice of language.

              I do not see any way of improving that set up without using an angle block. With the part securely fastened to an angle block, then that block can be gripped firmly in your vise or on a vertical mounted milling vise or on one of my milling plates. Oh, another thought hit me: I have a small screwless vise with ground sides (like the one in your photo but smaller) that I can easily mount at an angle in the jaws of a larger vise. The improvement here is the part can sit firmly against the bed of the smaller vise, effectively preventing any rotation. So a two vise set up may be another way of doing it.

              OK, I just thought of a third way. Use some paper or aluminum foil between the vise jaws and the part. That may improve the grip.

              Another thought would be to make it from a rectangular block of stock and mill that angled groove first. Then turn the OD to make a cylinder from that rectangle. This way you would be able to get a much better grip on the stock. Again, I can see this working with any of several ways of gripping it on the cross slide.

              Sorry, but I can't think of any magical way that my milling table would help here.
              Paul A.
              SE Texas

              And if you look REAL close at an analog signal,
              You will find that it has discrete steps.

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              • #8
                I was wondering, has anybody modified a V block to make it into a tailstock crotch center?
                Location: Saskatoon, Saskatchewan, Canada

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                • #9
                  Well, I am not sure what they call them in other places, but I would call them "PopSickle sticks". They are sold in bags of 100 or more at crafts stores. Hobbyists use them for all sorts of things including making houses and castles with them. If you do an internet search for that term you will get a gazillion hits.



                  Originally posted by pinstripe View Post

                  I would put something in to avoid the "steel on steel" situation. I've got a bag of these in the shop. Not sure what they are called in the US. They compress nicely, I have used them when milling roughly cut stock.

                  Click image for larger version Name:	reusable-bamboo-ice-block-popsicle-sticks-24.jpg Views:	0 Size:	21.8 KB ID:	1885428
                  Paul A.
                  SE Texas

                  And if you look REAL close at an analog signal,
                  You will find that it has discrete steps.

                  Comment


                  • #10
                    Originally posted by Paul Alciatore View Post
                    Paul of "Paul's sub plate" here

                    OK, I just thought of a third way. Use some paper or aluminum foil between the vise jaws and the part. That may improve the grip.

                    Another thought would be to make it from a rectangular block of stock and mill that angled groove first. Then turn the OD to make a cylinder from that rectangle. This way you would be able to get a much better grip on the stock. Again, I can see this working with any of several ways of gripping it on the cross slide.

                    Sorry, but I can't think of any magical way that my milling table would help here.
                    Thanks for checking in -- I might just do that with the sandpaper in the jaws. So far I am halfway through the job, taking less than .010 per. I would have loved to use the sub plate but it put the part up too high with my vee blocks -- would have had a pile of chips and no part! Starting with square stock would have been much, much easier but I don't have much of that at all -- mostly rounds and some offcuts of structural plate and bars.
                    25 miles north of Buffalo NY, USA

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                    • #11
                      Tongue depressors are the bigger sticks........Say .aaahhhh..
                      the set up shown, how are you even finding center? All gone with one slip.

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                      • #12
                        Originally posted by rklopp View Post
                        What is keeping the cylinder workpiece from tilting? Just friction? That's risky in my experience. Been there, learned that lesson the hard way.
                        I was thinking the bottom of his part was stopped up against the bottom of the vice so it couldn't tilt when he fed it into the cutter.

                        JL....

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                        • #13
                          Originally posted by pinstripe View Post

                          I would put something in to avoid the "steel on steel" situation. I've got a bag of these in the shop. Not sure what they are called in the US. They compress nicely, I have used them when milling roughly cut stock.

                          Click image for larger version Name:	reusable-bamboo-ice-block-popsicle-sticks-24.jpg Views:	0 Size:	21.8 KB ID:	1885428
                          I save mine after I eat the ice cream. They come in very handy for a little mixing stir sticks for various epoxies or two part mixes.

                          JL.....

                          JL....

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                          • #14
                            Peter, you are forgetting that there are another work holding devices at your disposal. MIG, TIG or OA... Tack a couple of "legs" to the part so that the jaws support one direction and the legs take care of the other. Grind off tack welds when done. After all, you are a welder!

                            Other easy way to do it is to pot the part in a flat bottom container of low temp melt metal. Woods metal, Cerrobend, etc. put it back in the vise and mill as desired, then dunk in hot water to melt away the metal. $10 a pound at www.rotometals.com

                            Dan
                            At the end of the project, there is a profound difference between spare parts and left over parts.

                            Location: SF East Bay.

                            Comment


                            • #15
                              Originally posted by danlb View Post
                              Peter, you are forgetting that there are another work holding devices at your disposal. MIG, TIG or OA... Tack a couple of "legs" to the part so that the jaws support one direction and the legs take care of the other. Grind off tack welds when done. After all, you are a welder!

                              Other easy way to do it is to pot the part in a flat bottom container of low temp melt metal. Woods metal, Cerrobend, etc. put it back in the vise and mill as desired, then dunk in hot water to melt away the metal. $10 a pound at www.rotometals.com

                              Dan
                              Dan, I would actually love to do any of those things, but they are not actually available to me at the moment. I still have my OA setup but no filler (and the part is 2" dia). If it wasn't for that, hrmmm... well, I *do* have 10 lbs of 7018 and some cables on another machine.....
                              25 miles north of Buffalo NY, USA

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