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Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
I found this vacuum pump and i was wondering if y=it would go down to 10 microns? I have seen someone use a vacuum pump made for refrigeration service that went to 10 microns and made his own tube and fixed a tube he broke.
I would like to make my own vacuum tubes and experiment with them and maybe make a lower voltage vttc with homemade vacuum tubes.
Registered Member #1451
Joined: Wed Apr 23 2008, 03:48AM
Location: Boulder, Co
Posts: 661
no, it won't. You need something along the lines of a two stage rotary vane pump. They can be found on ebay for less than 100 bucks. I have one from ebay that can go down to 5 microns that I got for $125. Just search for vacuum pump.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
I read an article, some years ago, by a school science teacher, who had successfully tweaked up a rotary pump sufficient to use it for demonstrating thermionic emission in simple diodes and triodes, but can not now recall the details.
Some applications - such as cold cathode X-ray tubes - actually require that the vacuum be slightly 'soft,' so hardness in a vacuum is not the be all and end all of the amateur scientist.
Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
Great! I have my answer! I suppose i will put off the idea of making my own vacuum tubes will have to be put off until i get a job. .....Or someone makes a generous donation Kidding of course...THoguh i think i have said that before...Hmmm.
Registered Member #113
Joined: Fri Feb 10 2006, 01:40AM
Location:
Posts: 49
I've had a good deal of luck with Robinair pumps. If you take off the fitting on top, it presents a standard o-ring boss seal. I've measured it down to 10 microns, and may be able to go a bit lower if you heat everything.
Registered Member #1225
Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253
Liam wrote ...
I've had a good deal of luck with Robinair pumps. If you take off the fitting on top, it presents a standard o-ring boss seal. I've measured it down to 10 microns, and may be able to go a bit lower if you heat everything.
Well at some point i will get one. But that is when i have enough money and i still need to make equipment and i need to learn glassblowing. My first versions will probably be built into a mason jar. The guy on that site had a tube he made and he used a mason jar as low as 10 microns and it did not blow up(implode).
Registered Member #135
Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735
I was getting into the same things before I started working (aerospace) and had the time.
I think the hardest part is knowing the glassblowing because it requires so much practice. But the vacuum stuff is a real expensive hobby. Along with the 2-stage and diff or turbo (turbo requires a special controller), you will need a cryo-trap(~ $600), various poppet valves, Getter metal to trap gasses, Ion gauges or a Magnetron gauge, electrode wire, and electronic glass (which is kinda hard to find now that nobody really makes tubes on a big scale) and sometimes pure gum rubber hose which can be very expensive stuff.
I just got a pump rebuilt, cost $500 and was a big dent in my savings, but that's vacuum, just one of those expensive hobbies.
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Is this pump good for vacuum tubes?
Kidding of course...THoguh i think i have said that before...Hmmm.
