The only gauge I can think of would be a standard "U" gauge (manometer), but that is only practical down to a few millibars with mercury. Maybe there are some exotic liquids with low vapor pressure that might work a bit lower, but I doubt anything exists that would get you into the micron range.
For vacuum levels into the micron range, you need something like a Pirani gauge, and that requires external connections. On Monday, August 28, 2023 at 11:18:09 AM UTC-7 Miles Thatch wrote: > Actually there was something else I was wondering about. > > Is there such a thing as an accurate vacuum gauge which you can just drop > into a chamber instead of connecting to the valve / air line of the pump? > Conceivably it's something that has it's own sealed air container and would > detect the expansion force / difference between external and internal > pressures? > > On Monday, August 28, 2023 at 2:16:13 PM UTC-4 Miles Thatch wrote: > >> Thanks for the read references. I know this group has a shared drive with >> some reading material. Maybe I can find some of these there. >> >> I'm primarily interested in making a few special character display nixies >> like the in-12 tubes. More experimentation than anything. I've seen a gent >> on Youtube make one in his garage. >> >> >> On Monday, August 28, 2023 at 1:56:37 PM UTC-4 gregebert wrote: >> >>> I did a lot of research about 15 years ago when I was thinking about >>> doing neon art. There are 3 really good books (The Neon Engineer's >>> Notebook, Neon Techniques, and The Neon Superguide) and I recommend you >>> read all 3 cover-to-cover. Though not particularly for nixies, there is a >>> lot of good info about the overall process. I have yet to read the Weston >>> text (Cold Cathode Glow Discharge Tubes). >>> >>> You will need to pump down to the micron range, and that generally >>> requires a diffusion pump ( a fascinating device, and another topic on it's >>> own...) in addition to a traditional vane pump that will get you well-below >>> the millibar range. I decided against doing neon art because the bombarding >>> process is very dangerous; far more dangerous than experimenting with >>> microwave oven transformers. >>> >>> The manifolds I saw were made of glass, even the valves, and require a >>> special lubricant/sealant. I think you can use induction heating, rather >>> than bombarding, for removing impurities. The other thing that discouraged >>> me was the need to use mercury; it's rather toxic and I was concerned about >>> inhaling vapors. I'm not afraid of mercury in liquid form. >>> >>> Keep me posted if you start experimenting. I have a vacuum pump and >>> intend to do some basic tinkering with gas discharges, but I have no >>> intention of taking it to the point of making something durable. >>> >>> On Monday, August 28, 2023 at 10:23:32 AM UTC-7 Miles Thatch wrote: >>> >>>> I'm looking to experiment with making a cold cathode character display. >>>> I have plenty of experience experimenting with manufactured IN-12 tubes >>>> and >>>> the power supplies that drive these, but I want to step further to >>>> experiment in making my own. >>>> >>>> What grade of materials / tubing / valves should I be looking at to try >>>> and build my own jig for evacuating air from a tube and populating a gas? >>>> >>>> I don't suppose just about any valve with do (like liquid control >>>> valve) and looking at my hobbyist grade vacuum chamber, the tubing >>>> contains >>>> a spooled wire on the inside to provide rigidity to counter the vacuum >>>> forces. >>>> >>>> Would brass / copper tubing sealed with aluminum weld be suitable? >>>> >>> -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/5a2fb9e6-8359-4a1b-99c5-8f37d682c71dn%40googlegroups.com.
