It’s o-rings and spacers stacked and compressed, pushing the o-ring out like an expansion collet.

    • BuglefingersEnglish
      2•3 months ago

      The whole thing is a lathe, yes, but what they are pointing out is the fixturing on the lathe. Specifically the piece in the chuck that can clamp onto the ID of a work piece to be cut. Which is pretty neat!