Ultra high molecular weight polyethylene-what kind?

Discussion in 'The Okie Corral' started by Maelstrom, Apr 8, 2010.

  1. Maelstrom

    Maelstrom MiniCapitalist

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    UHMWP Rod, approx. 1.75 diameter, Grey or even Black would work.

    I need some to get a prototype "sleeve" device made before we file a provisional.

    There seem to be many brands/types. What would have the lowest friction coefficient? This thing must rotate easily on the aluminum "barrel" it is going over.

    Anyone have a good source?

    I've been impressed at what the GT hive mind has available!

    And..thanks!
     
  2. USDMike

    USDMike

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    Slip additives will have more of an effect on the coefficient of friction i would think.
     

  3. Maelstrom

    Maelstrom MiniCapitalist

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    Hmm, slip additives? These a liquid? Google pages that come up are technical manuals.
     
  4. Jay S.

    Jay S.

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  5. 220-9er

    220-9er

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    What about teflon?
     
  6. janice6

    janice6 Silver Member

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    I used to use Delrin a lot in research work. Cheaper substitute for Teflon. There are "filled" versions that are very nice to machine.
     
  7. Maelstrom

    Maelstrom MiniCapitalist

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    Thanks for the replies! GT Hive mind knows all!
     
  8. Adjuster

    Adjuster

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    I worked in plastics as well. Delrin is easy to extrude/mold, very hard, machinable and extremely slippery. The white bottom part of a Bic lighter, thats Delrin for an example.
     
  9. Ronaldo

    Ronaldo Ancient Member Millennium Member

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    +1 for Delrin. I have used it for years in model-making and prototyping of parts. Very easily machinable and not expensive.

    ronaldo
     
  10. Maelstrom

    Maelstrom MiniCapitalist

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    Does it thermally insulate as well? It will be forming a chamber that will have very cold air blowing though it and someone will be holding onto the thing.
     
  11. Adjuster

    Adjuster

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    Now the thermal thing might be an issue. I would think depending on thickness the Delrin will get pretty cold. I am also not to sure on how extreme cold might effect Delrin. It may become brittle or at least more brittle than under normal temps.
     
  12. Maelstrom

    Maelstrom MiniCapitalist

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    I thought about getting some of that grip stuff that used to be a sponsor or GT. It had a video of someone using a blowtorch on it. It was like a velvety deal.
     
  13. elsolo

    elsolo

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    Just spend a couple minutes on McMaster-Carr's website.
    They sell all the popular raw materials in many shapes and sizes, the section will also list their properties and explain them too, usually in a chart comparing the choices they offer in that category. Quick phone call and you have it the next day.

    UHMW is soft, it can be deformed, dented, or gouged rather easily. It does have low friction, doesn't shatter and is chemically inert. It's harder to machine to a nice surface finish compared to say Delrin. It does not seem like the ideal choice for the application the OP is undertaking

    http://www.mcmaster.com/#plastics/=6r6qgu

    http://www.mcmaster.com/#plastics/=6r6now
     
  14. Maelstrom

    Maelstrom MiniCapitalist

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    Thanks for the links!

    Would you concur that Delrin would be the appropriate choice? It won't be used in a high impact environment, but it does need to be slippery.
     
  15. elsolo

    elsolo

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    Delrin will machine nice, have low friction, look good, and is very popular for a reason.
     
  16. Maelstrom

    Maelstrom MiniCapitalist

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