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Does nyone know how I can create a vacuum plate? Similiar to a vacuum tub but entirely flat?
I was thinking of a 12x12in plate siliconed on top of another with a few rubber spacers in between to prevent it from bending in, leaving a tube in the silicone and pumping out the air
id like to see what people think before I attempt, I don't want glass shattering lol or wasting hours
this is gonna be hooked up to a high voltage supply and hopefuly work similiar to a plasma globe aat best(I know it need certain inert gases) or at worst a very large flat vacuum tube
which if I were to put filaments in there how could I? I don't really have. Supply of tungsten or anything....
and help is appreciated
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Are you making something like a LumiDisk (http://www.amazon.com/Discovery-Channel-2264-Rainbow-Lumidisk/dp/B001ASQNUC) or Lumin Disk (http://www.amazon.com/gp/product/B000PNO00S)?
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That looks cool, never saw that before
and sorta although I was thinking clearer and more of a corona discharge look than an actual plasma, less bright and more purple hue
other than the assembly, I don't know what kind of electrode would work best, I was thinking two strips on either side or even a mesh inside
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I don't think that silicone seal work well for high vacuum.  You could try to melt the glass together.  A propane torch is hot enough to melt glass.
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I happen to have one, hmm some experimentaion is in order
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There's a reason that vacuum tubes are tube-shaped.  It's so they can withstand the atmospheric pressure forces when the air is sucked out.  The curved shape of tubes and globes actually make those structures stronger as the external pressure increases. 

Your plate won't have any of that going for it.  If you use a high vacuum, each side of your your plate will feel a force as high as 12*12*14.7=2116.8 pounds.  I think 1 ton per side would be enough to break the glass, unless you use something thick like a telescope mirror blank or a porthole glass. 

Try a smaller plate first.  You don't have to use silicone rubber, and you probably won't need to glue it, either.  The good news is that as you lower the internal pressure, the increased force will squeeze the rubber more, actually improving the seal.  Use a stiff grade of rubber.  If the rubber is too soft, it may squeeze down too much leaving you no gap.

Good luck with your project! 
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Yeah I thought perhaps of rubber spacers spread conviently throughout the glass to help keep it from shattering
I tried the blowtorch and while I did melt it, it doesn't seem viable for me to seal it with just a blowtorch and lack of glass skill, ended up just bending a piece then it cracked near the joint I guess uneven heating, so I dipped it in water and it entirely fractured, pretty cool looking actually
im usin some other smaller pieces of glass for a test run, aout 2x3inches on the inside of the silicone, I placed a plastic tube inside(pretty small one maybe 1/4 outside diameter, and a few rubber washers at the corners to make it all even, and a wire at each end for electrodes, then siliconed a good 1/2 all the way around, and while it took some patience to get it airtight I think I got it, ill find out tomorrow when I hook up the vacuum pump

That rubber seal makes sense, but how would I get the air out in the first place if itch has a rubber ring around it? And I guess the thinnest possible would be the easiest to pump, but how small do you think is practical?
Thanks for the help so far, I hope this comes out cool, I got the idea from an automotive bulb that I purposely blew the filament on, and hooked up to a modifed laptop flourescent driver and got a real neat effect
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Heres the effect


* 070812165111.jpg (580.72 KB, 1280x720 - viewed 51 times.)
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Again


* 2012-07-09_18-36-11_657.jpg (1192.03 KB, 1840x3264 - viewed 47 times.)
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Quote
...how would I get the air out in the first place if itch has a rubber ring around it?

Try poking a hypodermic needle right through the rubber ring, then stabilize it so it doesn't move around or fall out.  Not too small either or it will take forever to pump the air out - maybe a 20 or 22 gauge (green or yellow band). 

Quote
And I guess the thinnest possible would be the easiest to pump, but how small do you think is practical?

Actually the gap between the plates will not affect how hard it is to pump.  The bigger the gap, the LONGER it will take to remove the air.  You might have small leaks, and some air will go right through the silicone, so you will probably want to leave the pump running.

Now I have some questions.  The bulbs in the photos have no filaments?  What is a laptop fluorescent driver?  How is it modified?
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I used a charged 200v cap to blow out the filament so I can use it to arc the two terminals,
the driver had a open circuit failsafe so I had to solder from a via to a nearby cap to disable the safety, otherwise it would only turn on for a split second unless I had the other end grounded so it could arc, but then it wouldn't give off that cool corona discharge
I looked up the datasheet and it was either build a circuit to replicate the closed circuit voltage (2vac with a 5v offset) to keep the short circuit safety still working or short out a pin to ground to disable both safeties
its pretty cool, draws alot whe. Its fiving out the corona disharge, >10amps if I have my whole hand on the bulb, .3amps If an arc is struck

Where could I get a syring like that? I definetly don't want to have to pump hooked up all the time


* 2012-07-13_00-57-50_898.jpg (1359.11 KB, 1840x3264 - viewed 28 times.)
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That's pretty cool!  I have not done any projects with high voltage yet, but when I do I may start with the bulb.

I work in the medical device industry where needles are common.  Not sure where to buy them retail.  Try calling your doctor, dentist, or veterinarian and tell him what you want it for. 

You may want to use a valve or stopcock on the vacuum line so you can disconnect it from the pump after the cavity is pumped down.  If you just pull out the needle, some air may leak in.
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Well on my first trial attempt the glas cracked, a little silicone fixed that,
it still leaks slowly but only over like an hour
a regular tube worked fine, I just bent it over itself twice and clamped it, maybw that was the cause of the leak
my gap of 2inch is too large to arc across directly with the laptop driver, ill have to finish my HV supply first I guess, hopefully 15kv will be enough, I don't think this went much over 1kv
im definetly gonna need rubbers spacers throughout the inside, which kinda takes away from the look, maybe ill find thicker glass this is maybe 1/8 window pane glass
it did corona a little on the wire definetly not as much as I would like, perhaps because I don't think it got too low of a vacuum
I used a refrigerant vacuum pump, anyone know if perhaps it isn't strong enough? I don't know the different types of pumps
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Yeah I thought perhaps of rubber spacers spread conviently throughout the glass to help keep it from shattering

You could do what the LumiDisk seems to do: fill the gap with glass beads.
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I could but I was really hoping for a clearer look, maybe clear silicone blobs spread evenly or even in some neat pattern, or perhaps ill try for a grid and have some aluminum tape as my electrode throughout, although then it would be harder to pump out
I think ill try with the spacers with the glass I have salvaged, and if it doesn't work ill just find more glass
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