On 9/30/2012 11:45 PM, Kirk Wallace wrote: > I'm playing with the thought of putting a vacuum deposition system > together to coat telescope mirrors with aluminum. It looks like I could > get everything I need from eBay at relatively low cost. Of course, > elements of LinuxCNC could be used to monitor and control the system. > Does anyone have any links to a system I could study or copy, or any > other information? One issue is what I need for a pressure gauge, a > Pirani and or ionization gauge? > > So far I've found: > http://belljar.net/forum/index.php > http://www.public.asu.edu/~aomdw/GLASS/ > http://www4.nau.edu/microanalysis/Microprobe/Vacuum-Overview.html > Kirk:
It's been 40 years since I did any serious sputtering (mostly coupons and filters, not mirrors) but the bottom line is you need a gauge which will provide useful readings at working pressure. I seem to recall we wanted pressures (ca 10^(-5) Torr), beyond the working range of most Pirani gauges. Typically, we had a christmas tree of aneroid gauge, thermocouple gauge, Pirani gauge, and Penning gauge or some such, to cover the pressure range, but we wore belts and suspenders:-) Hmmm. I believe there were "recent" (end of the last century) Amateur Scientist columns on the subject but I have to find my collected-works cdrom to check. Hmmm, part 2. See http://www.finishing.com/4200-4399/4359.shtml Hmmm, part 3. See the Yahoo group http://groups.yahoo.com/group/vacuumx/ Finally, Peter Albrecht, who once upon a time worked with me at Argonne National Laboratory, has become well known in amateur telescope circles. Look for messages by PLAlbrecht. I'm sure he'd respond to queries. As my grandkids grow, I feel the itch to have a vacuum bench in the basement for "Ask Mr Wizard" kinds of experiments. Anything so long as it doesn't generate X-rays. Good hunting! Regards, Kent ------------------------------------------------------------------------------ Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
