These are the least expensive valves that I can think of @ $40/ea.

http://www.swagelok.com/downloads/WebCatalogs/EN/MS-01-59.pdf

20 mT base is close to the end of rough vac are you certain that the pump i=
s capable?

-----Original Message-----
From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of=
 David VanHorn
Sent: Sunday, November 01, 2015 1:07 PM

I have a vacuum project in the works, and I've just isolated one source of =
leaks.
The system needs three shutoff valves.  I used ball valves, and I'm finding=
 that they are leaking. Probably designed for positive pressure I'm guessin=
g.

Is there someone on the list with vac experience down around 20 microns who
could suggest relatively inexpensive valves that I could use?   The system
is now built with 1/8 NPT but I could switch if I need to.

These valves just need to be on or off, and they are used for controlling t=
he flow of air and other gases. No liquids, nothing harsh.

Thanks.

--=20
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