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988 days ago in


Does anybody know what the 75 micron means on the 6 cfm master cool pump?

On the 3 cfm it says 25 micron on the 6 cfm it says 75. Just wanted to know what that is. I think it is for the filter.

  • Answers (2):

  • User Submitted Answers:


  • Dunn
    988 days ago

    Im no pro lol but i think the lower the number the better from what i seen and heard

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  • JGwntworth
    988 days ago

    concept of microns, as it relates to vacuum, is easy to understand. Atmospheric pressure measures around 759,968 microns. The deeper the vacuum, the closer we get to 0 microns. By that, we could look at the vacuum pump as a micron remover.

    higher CFM or super low micron ratings is not necessarily needed from my understanding, but the ability to pull a micron level of 50 or lower is ideal. check out this little math diagram if you got the time

    obviously shows 50 micron pulls -29.91 which is good enough, so 25 microns and 15 microns may not even be needed for our application

    If i had to choose between those two pumps you listed i would definitely go with the 3cfm 25 micron

    3 users found this HELPFUL
    • LeeBoi
      988 days ago

      Thanks for the info. I saw Bretmaverick uses the 6 cfm because his chamber is the 3 gallon size. He said it was needed for bigger chambers.

    • JGwntworth
      988 days ago

      Sure there are gonna be variables to this such as chamber size , altitude ect. From my research a CFM rating as low as 1.5CFM is sufficient. The general chambers that most people use are 10 – 20 Liters in volume if bret maverick used a 3 gallon chamber that would mean it had a volume of 11 liters

      *1.5 cubic foot/minute = 42.475 270 499 liter/minute
      3 cubic foot/minute = 84.950 540 998 liter/minute
      5 cubic foot/minute = 141.584 235 liter/minute
      6 cubic foot/minute = 169.901 082 liter/minute

      *and therefore would take around 30 seconds to displace the air (free air displacement is what CFM is a rating of)

      in my opinion brett mavericks pump is alittle over kill not saying anything wrong with that but like i said my research has proved a 1.5cfm to be sufficient I personally use a 2-stage 3cfm 25 micron pump works amazing

    • LeeBoi
      988 days ago

      Thanks again for the info. Much appreciated. By the way, “I want my money and need it now”. Lol.

    • JGwntworth
      988 days ago

      No problem Leeboi… lol yea “it’s my money and I need it now every cent worth” JgWentworth