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From: mcdonald@aries.scs.uiuc.edu (Doug McDonald)
Newsgroups: sci.bio,sci.chem,sci.physics
Subject: Re: Fun With Vacuum Equipment
Message-ID: <1991Jan16.155313.18147@ux1.cso.uiuc.edu>
Date: 16 Jan 91 15:53:13 GMT
References: <38073@cup.portal.com> <1991Jan16.121112.23208@en.ecn.purdue.edu>
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Organization: School of Chemical Sciences, Univ. of Illinois at Urbana-Champaign
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I have used motor oil (30 weight single-grade, the very cheapest,
the brand name is "Saphire" , for years, in vacuum pumps. I get
a pressure of about 180 microns at first, dropping in a day or so to
about 50 microns. We did this because we had to change oil every week or so -
we were running fluorine through the pump, which makes a big mess.

Doug McDonald