The other problem is cooling. The freon and oil charge carry heat away
from the compressor which is probably why Glenn's tripped the thermal
switch. Before I got a "real" vacuum pump I used refrigeration
compressors successfully by cooling with a fan and constantly
lubricating thru a bleeder on the vacuum side with one of those air line
oilers made for lubing air tools. WD40 is not a very good lubricant for
this, I used light oil and sometimes even thinned motor oil with
kerosine. I also had an old airbrake compressor off a bus that I drove
with a 1 hp electric motor. I spite of the physics, I believe I could
have pulled 25 psi with it (maybe thru a worm hole from Jupiter). On
the output side she would put out 300 psi. All of this was back when
vacuum pumps were a lot more than $50 on Ebay.

Regards, Ron

PS. Fred, re-read my earlier post please. You will find it was
not directed at Glenn.

Ron Thornton ) writes:

... I spite of the physics, I believe I could
have pulled 25 psi with it (maybe thru a worm hole from Jupiter). On
the output side she would put out 300 psi. All of this was back when
vacuum pumps were a lot more than $50 on Ebay.

another PSI supporter, "Pressure Scale Inches" (of mercury).
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William R. Watt wrote:

Ron Thornton ) writes:


... I spite of the physics, I believe I could
have pulled 25 psi with it (maybe thru a worm hole from Jupiter). On
the output side she would put out 300 psi. All of this was back when
vacuum pumps were a lot more than $50 on Ebay.


another PSI supporter, "Pressure Scale Inches" (of mercury).

Oh, NO! Not another measure! We have enough already! ;-)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Glenn Ashmore" wrote in message
news:rr0lb.80765$sp2.32669@lakeread04...


Oh, NO! Not another measure! We have enough already! ;-)

Yes, but how many barnyard atmospheres would that be?

(both are recognized as official measurements)

"Matt/Meribeth Pedersen" ) writes:
"Glenn Ashmore" wrote in message
news:rr0lb.80765$sp2.32669@lakeread04...


Oh, NO! Not another measure! We have enough already! ;-)

Yes, but how many barnyard atmospheres would that be?

(both are recognized as official measurements)

the barnyard atmosphere on my grandfather's farm was usually pretty high
due to a combination of barnyard manure and barnyard language
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"Ron Thornton" wrote in message
...
I spite of the physics, I believe I could
have pulled 25 psi with it (maybe thru a worm hole from Jupiter).

no ron, you couldn't pull 25psi with it, no matter what you believe. the
amount it put out on the high pressure side won't help you there.

hugh

p.s. having worked on a bunch of different projects over the years i'm
surprised to see people going to so much trouble trying to make - as they
say - a silk purse out of a sow's ear. experience has told me many times
(and keeps doing so whenever i try to cheat it) that the cheapest way of
doing something is to buy the right equipment for the job rather than trying
to "make do" with something else. as glenn already said, it's also a good
way to ruin a lot of expensive materials.