No announcement yet.

Off-center turning

  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Originally posted by winchman
    You can also use a combination of inside jaws and outside jaws for holding irregular shapes and doing off-center turning.
    Thanks did not think of that, pretty clever.
    If you are using violence and it does not work, You are not using enough or it is upside down.
    You can always just EDM it...


    • #17
      Anyone remember this thread ?

      I didn't get as much flack over this and it wasn't that different.

      Sir John , Earl of Bligeport & Sudspumpwater. MBE [ Motor Bike Engineer ] Nottingham England.


      • #18
        I just checked your thread ... really nice job.
        That one will go into my bag of tricks next time I need to machine a strange part.
        I know the whole issue with my setup was safety and honestly I knew I was going to catch some flack and I'm fine with that.
        Getting back to safety here is a interesting video that will let the people that hide behind "safety first" think a bit.
        If you are using violence and it does not work, You are not using enough or it is upside down.
        You can always just EDM it...


        • #19
          Originally posted by Carld
          No I didn't see that. I would feel better if the spacer was welded to the piece in the 3 jaw and even that is chancy. He could weld a stub on the end of the chunk that is offset the distance he needs. There's a few ways to make it work.
          Italics mine. I think what you meant was "There's a few safer ways to do it."

          It's not a set-up I'm going to replicate, nor would I recommend it to anyone else, But I, too, wonder why this is getting so much flack. Any large offset mass is going to require the lathe to be slowed down and the cuts to be lighter. Packing pieces are used in all kinds of applications, both packing pieces and shims are going to reduce the grip between parts to some degree.


          • #20
            Why is it getting more flack, I don't know. The reason John's article didn't get much flack is he used a four jaw chuck. Any time you put something larger than a piece of shim to protect the work surface you have a chance of slinging it out and getting hurt. With the piece off center as much as it was in the 3 jaw it would have to be run slow so the chance of it flying very far is slim.

            Yes, I meant to say safer.

            The reason I have said anything at all is because many of the members here are very new to machining and if they see something like that setup they may think it's ok and try it. Since they don't have a clue about the danger of it getting slung out of the chuck they may start the lathe at 300 rpm or more and the lever effect of the off center weight would/could sling the chunk out with a vengeance in the direction of the operator.

            I have seen alleged machinists at places I worked do things just as dangerous more than once. You would think after the first failure they wouldn't do it again.

            Not intending to offend anyone, just pointing out any dangers.
            Last edited by Carld; 03-10-2011, 11:10 AM.
            It's only ink and paper


            • #21
              "many of the members here are very new to machining"

              exactly the motivation for the OP.

              I reread the entire thread, and while there are definite opinions expressed, I don't see anything I would characterize as flack - to include a complete absence of personal malice, and insults against the sainted name of Bridgeport ...