Silicone tubing with hose barbs OK to pull low vacuum?

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Shireesh Apte
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Joined: Sun Sep 10, 2017 10:16 am
Real name: Shireesh Apte

Re: Silicone tubing with hose barbs OK to pull low vacuum?

Post by Shireesh Apte »

Thanks Ian, Dennis,

After liberally applying loctite to my joints, I got down to approximately 100 microns in about 20 seconds with my rotary vane pump. The set up is not pretty but I figured it would be good enough for a plasma. I believe I did obtain a plasma today (see pictures attached). The gauge reads approx. 100 microns with a glow emanating from the central grid and becoming more intense as the voltage (or what I believe to be the voltage regulator knob on my Chinese electroprecipitator) is increased.
I have realized that I will need to intensify work on the vacuum part of my apparatus if I want to progress to fusion. However, I did get permission to buy the deuterium cylinder from school administration based on my plasma demonstration, so that saves me some money.
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Shireesh Apte
Posts: 26
Joined: Sun Sep 10, 2017 10:16 am
Real name: Shireesh Apte

Re: Silicone tubing with hose barbs OK to pull low vacuum?

Post by Shireesh Apte »

Many tanks to everyone on the board for the many useful suggestions. I will now start the long task of finding parts for - and assembling - a fusor.
Best,
Shireesh
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Dennis P Brown
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Joined: Sun May 20, 2012 10:46 am
Real name: Dennis Brown

Re: Silicone tubing with hose barbs OK to pull low vacuum?

Post by Dennis P Brown »

You certainly have created a true plasma. So congratulations on your success (Maybe PM Richard to include your name in the plasma club.)

Also, I thought you had a fusor chamber - that is, a four-way vacuum connector? If you have one of sufficient diameter, don't under value it. Those can make building a successful fusor easier.

I can't clearly read your vacuum gauge image but 100 microns is useful for a plasma, totally unacceptable for a DP based vacuum system that will be a fusor. When your system reaches 2 to 3 microns and exhibits a slow leak back rate, then you are ready for a diffusion pump and start of building a real fusor chamber that one can then hook up to a proper fusor power supply: remember, fusor supplies are always lethal so read the FAQ's on those systems and pay close attention to proper grounding. They are also significant x-ray hazards so a methodology to detect these is important.

As for deuterium gas, this is useless unless you have a power supply that is fusor capable. That is 20+ kV (with negative polarity) that can deliver at least two hundred watts of power or more (both more power and voltage is far better.) So, the next issue I believe, is what power supply do you currently have or are you planing on finding one? If you don't already have one finding those are difficult and not inexpensive. (Aside: a vacuum feed-thru that can handle both that level of power and voltage is important, too. I made my own but many just buy one - again, can be pricy.)

Finally, don't forget that one must prove they are doing fusion and that is a major issue that far exceeds the difficulties of building a fusor/vacuum system. Keep up the good efforts but you need to be aware that just adding deuterium to a plasma does not do fusion nor carries any importance in of itself - just another small step in building a possible working fusor.

As someone who often struggles myself with projects (my accelerator, for instance ... but you are seeing that in real time like most here; lol), I say these things to help guide you, as well as help you realize what to focus upon - not to discourage you; we all start somewhere and getting a plasma is the first real step in building a fusor.
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