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  • Metalurgy

    What is "Pot Metal" ? How does the thermal expansion and contraction
    compare to CR1018? I am thinking about making a heavy base for my
    Sherline ( I can hear the laughter from here) lathe.

  • #2
    Pot metal is a generic term for a variety of zinc alloys, such as the various ZAMAK alloys. Here's some data that might be useful. Looks like the coefficient of thermal expansion is around double that of 1018.

    I'd never laugh at your Sherline. I love mine.
    Last edited by Todd Tolhurst; 01-18-2007, 08:03 PM.


    • #3

      Thanks for the info Todd. I want to make a metal base to add weight. The guys at Sherline said that the existing bases on their lathes were "pot metal".
      I tested with a magnet and didn't get any reaction. Thats's why I asked them. The Sherline stuff was a great thing to learn on. With a small fractional
      HP motor, mistakes are not as dangerious as the big machines. Great for small work though.


      • #4
        Use lead. I bought 75 lbs of lead for $10 from a local tire shop in the form of wheel weights last summer. I melted it and cast it to make a counterweight for my mill. It would be easy to make a base for the Sherline and the coefficient of expansion is in the same range as zinc alloys.

        Come to think of it, that's a really good idea. I think I'll make a base for my Unimat from lead. The damping is unbeatable. I still have about 30 lbs left. A cookie pan would be perfect for casting in.
        Last edited by Evan; 01-18-2007, 11:44 PM.
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