I can tell you flat out that even a 90% vacuum conducts VERY well and you NEED a 2 stage pump. Otherwise stay with a full atmospheric pressure collector. There is very little difference between 1 atmosphere and 0.1 atmosphere. I know this from experience.
Kirk --- Doug Foskey <[EMAIL PROTECTED]> wrote: > Hi, > 2 sources of vacuum pumps: Medical & off diesel > cars. I have used an > ex-medical vacuum pump to transfer liquid. They will > usually evacuate to > about -1/2 atmosphere, or about -3.5 lbs. Car vacuum > pumps are not as good. > Most pumps require oil mist for lubrication, but > this can be introduced near > the pump. (note that sucking up methanol using a > catch jar, & vacuum pump can > result in the pump seizing due to lack of > lubrication, & presence of methanol > vapour: guess how I know?? > > regards Doug > > On Monday 07 February 2005 8:23, Stanley Baer wrote: > > I am very interested in building vaccuum solar > heating tubes as well. I > > have not looked into it in depth buth if you only > need a bit of a > > vaccuum you may be able to get it by using an air > compressor and a > > venturi. A used vaccuum pump might be available > on ebay at an > > attractive price. Keep me posted if you do any > actual expeiments. > > > > stan > > > > > > _______________________________________________ > > Biofuel mailing list > > [EMAIL PROTECTED] > > http://wwia.org/mailman/listinfo.cgi/biofuel > > > > Biofuel at Journey to Forever: > > http://journeytoforever.org/biofuel.html > > > > Biofuel archives at Infoarchive.net (searchable): > > http://infoarchive.net/sgroup/biofuel/ > _______________________________________________ > Biofuel mailing list > [EMAIL PROTECTED] > http://wwia.org/mailman/listinfo.cgi/biofuel > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Biofuel archives at Infoarchive.net (searchable): > http://infoarchive.net/sgroup/biofuel/ > __________________________________ Do you Yahoo!? Yahoo! Mail - Find what you need with new enhanced search. http://info.mail.yahoo.com/mail_250 _______________________________________________ Biofuel mailing list [EMAIL PROTECTED] http://wwia.org/mailman/listinfo.cgi/biofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuel archives at Infoarchive.net (searchable): http://infoarchive.net/sgroup/biofuel/
