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Oil Viscosity & LT Stirling

  1. Dec 24, 2009 #1


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    I have been doing a bit of research on building a low temperature Stirling engine, and I came across this website,


    The design on this website looks nice, and I would like to give it a go (after I build a simpler model), but I have my doubts about the following statement within the instructions.

    Any thoughts on this? I understand oil could be a bit viscous, but it wouldn't seem to be so dramatic that you would want to run this engine dry.

    *EDIT* Be sure to hit the "English" button at the very top of the webpage.
  2. jcsd
  3. Dec 24, 2009 #2
    It looks cute, but the RPM is unimpressive, to say the least, as those props want to turn around 5-6 thousand rpm to generate any appreciable thrust.
  4. Dec 24, 2009 #3


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    Well, I don't believe it's designed to be anything more than a toy. I personally want to build it just so I can get a better understand of the inner workings of a Stirling. Plus, it runs on a coffee cup. I mean how cool is that?

    I will be starting to build this one in a day or so,

    http://www.physics.sfasu.edu/astro/courses/egr112/StirlingEngine/stirling.html [Broken]

    but I am still curious about the "To oil, or not to oil" situation. This one calls for a thin coat of oil, whereas the other one says not to use it.
    Last edited by a moderator: May 4, 2017
  5. Dec 29, 2009 #4
    oil can have a significant effect on mechanical performance. even a very light oil will slowly thicken over time, grab dust from the air, and change with humidity. Thats why most dial gauges, watches, and other precision mechanicals use no oil. In some of our precision pneumatic equipment, just the residual oil from a finger will prevent its function.
    nice links, but the english conversion didn't change the main text
    (I was bummed...looks interesting...must learn dutch now...lol)

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