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Is it OK to post OT (on topic) machining stuff?

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  • Is it OK to post OT (on topic) machining stuff?

    Neighbor came over last week with his latest emergency project for the company he works for. He needed some washers of a precise ID & OD made from some tough material.

    I first made a slitted sleeve of thin-wall alum tubing to hold them by the OD in the 4 jaw. Then an acetal plug was turned to the OD size of the washers to help hold them straight while the chuck was final tightened & the ID dialed in.



    I then used a conical fitting in the tailstock live center to help align the washers & press them hard against the acetal plug as the chuck was final tightened & dialed in.



    The ID was then bored to the specified .430” +.001/-0”.



    A mandrel was turned to be a snug fit to the washers' ID & dialed in before they were clamped in place with a 5/16” bolt. The OD was then turned to the specified 1.110”.



    Earlier I mentioned the washers he brought were made of tough stuff but unfortunately I didn’t get a picture of the bluish mass of SHARP steel wool that was stuck hard to the OD after the finish pass. Fortunately it cleaned up well with a few strokes of a fine file. It’s funny how the ID cut OK but the OD sucked. SFM I guess.
    Milton

    "Accuracy is the sum total of your compensating mistakes."

    "The thing I hate about an argument is that it always interrupts a discussion." G. K. Chesterton

  • #2
    They came out great & so far I haven’t heard a discouraging word so I guess they’re happy. Let’s see if they’re still happy when they get the bill!

    Milton

    "Accuracy is the sum total of your compensating mistakes."

    "The thing I hate about an argument is that it always interrupts a discussion." G. K. Chesterton

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    • #3
      Looks good. You may have been able to save a little time by turning the OD first and then boring the OD size into a set of soft jaws on the mill and then doing the ID there.

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      • #4
        Washers are always a pain to work with. I like your split sleeve OD gripper. Hopefully I'll remember that when the time comes again. Thanks.

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        • #5
          Now see if I tried that the original O.D.'s would be off enough to allow one to not be held and slip whilst machining basically forming a mild eccentric and taking out a very expensive carbide insert.... just sayin...

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          • #6
            Yes I like the split sleeve idea as well, thanks for the OT subject matter , and the photos.

            It’s funny how the ID cut OK but the OD sucked. SFM I guess.
            I wonder if it is not more related to the different tool geometries you used between the boring and turning operations.
            Home, down in the valley behind the Red Angus
            Bad Decisions Make Good Stories​

            Location: British Columbia

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            • #7
              Originally posted by A.K. Boomer View Post
              Now see if I tried that the original O.D.'s would be off enough to allow one to not be held and slip whilst machining basically forming a mild eccentric and taking out a very expensive carbide insert.... just sayin...
              Been there, done that, got the chipped insert! I checked the OD's on these 1st & they looked pretty good. I figured the soft tubing sleeve & the acetal plug would give enough to hold OK.
              Milton

              "Accuracy is the sum total of your compensating mistakes."

              "The thing I hate about an argument is that it always interrupts a discussion." G. K. Chesterton

              Comment


              • #8
                Originally posted by A.K. Boomer View Post
                Now see if I tried that the original O.D.'s would be off enough to allow one to not be held and slip whilst machining basically forming a mild eccentric and taking out a very expensive carbide insert.... just sayin...

                That's a great Jig,Boomer I have noticed when restocking my Washers that different batches or Manufacters vary a lot dia and thickness.If you get lucky one bunch will be the same.

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                • #9
                  While we are on the topic of washers, has anyone ever cut a small recess on the tips their lathe jaws to hold washers? I have one chuck with serrations across the jaws every 1/4" or so and I sometimes am able to get thin washers to wedge into the serrations to hold them square but it's a PITA to change chucks just to bore out one washer and if it's not thin, the serrations don't work.
                  Location: Saskatoon, Saskatchewan, Canada

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                  • #10
                    The split sleeve is a clever idea. Buuuuuuuut.... just thinking that if it were a thicker wall like pipe you could have turned a shoulder in the ID to seat the washer against so it was held true right away?

                    Mind you what are the odds that we have just the right pipe on hand... I know that it hardly ever happens for me.
                    Chilliwack BC, Canada

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                    • #11
                      Originally posted by Arcane View Post
                      While we are on the topic of washers, has anyone ever cut a small recess on the tips their lathe jaws to hold washers? I have one chuck with serrations across the jaws every 1/4" or so and I sometimes am able to get thin washers to wedge into the serrations to hold them square but it's a PITA to change chucks just to bore out one washer and if it's not thin, the serrations don't work.
                      Would work OK if you have extra set of soft jaws. I Wouldn't necessarily bore my normal jaws.

                      In OP's case I would have most probably just use the serrations in the jaws or swap to OD jaws if they have suitable gripping location. But I like the "mass production" approach for the boring job nonetheless.
                      Jobs like these would be yet another reason to complete my adjustable spindle bore stop..
                      Last edited by MattiJ; 02-11-2019, 03:50 AM.

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                      • #12
                        Originally posted by DICKEYBIRD View Post
                        Neighbor came over last week with his latest emergency project for the company he works for. He needed some washers of a precise ID & OD made from some tough material.

                        I first made a slitted sleeve of thin-wall alum tubing to hold them by the OD in the 4 jaw. Then an acetal plug was turned to the OD size of the washers to help hold them straight while the chuck was final tightened & the ID dialed in.
                        Very nice solution. If a job can ever pay for it, pie jaws are great for something like this.
                        Abbott jaws
                        At Travers Tool
                        Sherline


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                        • #13
                          I would use a collet like these (grossly overpriced) on the museum's lathe: https://www.ebay.co.uk/itm/smart-and...y4n:rk:15:pf:0

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                          • #14
                            Arcane,

                            Yes, I use the serrations all the time when dealing with washers. If the washer is too thick for this I hold a flat piece of steel across the front of the jaws and pinch the washer against it while tightening the jaws on the washer.

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                            • #15
                              Some of you are assuming he has soft jaws. Not everyone has them or can justify the expense.
                              The shortest distance between two points is a circle of infinite diameter.

                              Bluewater Model Engineering Society at https://sites.google.com/site/bluewatermes/

                              Southwestern Ontario. Canada

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