DEMO-FUSOR, How much can it take?

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keelan
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DEMO-FUSOR, How much can it take?

Post by keelan »

Greetings!
So I'm slowly gathering materials for a Fusor, but in the mean time I wanted to get used to high voltage, and vacuum technologies. I built one of the small bell jar Demo-fusors, but now I'm ready to test my new high powered roughing pump. I want to try it on my bell jar Fusor but I'm worried the glass won't hold up to that kind of pressure ( This pump should bring it down to around 30 microns). CAN the bell jar (of any kind) withstand that kind of power??? Additionally I know have a better transformer that can produce up to 10,000v and I am wondering if i need to be worried about X-rays of the 10Kev flavor being spewn out of such am environment? I am aware that most X-rays are emited around the 15Kev range. Why is that and if there will be x-rays at 10Kev, will I need more than 2mm of alluminum shield from them? What are some good shielding materials? All posts appreciated!
"What Mr. Einstein has said is not so stupid"-Wolfgang Pauli
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Aidan_Roy
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Re: DEMO-FUSOR, How much can it take?

Post by Aidan_Roy »

Keelan,

FAQs are a great resource and contain answers to these kind of questions and many more. Make sure to read through them as you continue your journey toward your goal.

Aidan
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Richard Hull
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Re: DEMO-FUSOR, How much can it take?

Post by Richard Hull »

All bell jars must be of thicker pyrex, kimax, borosilicate glass and be designed for a scientific vacuum. The little thin walled soda glass bell jars to cover flower displays or terrariums found in craft stores will implode due to pressure issues or glass heating by the ion/electron beams.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Dennis P Brown
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Re: DEMO-FUSOR, How much can it take?

Post by Dennis P Brown »

One can cut the ends off thick-walled wine bottles, cut a simple gasket for a small Al plate, and make an excellent vacuum chamber; however, not for a fusor. The ions in a fusor plasma are too agressive. But to test your pump it is a simple solution for an easy to make vacuum chamber. If your goal is a fusor, then making a standard four-way cross system is just too easy not to do. Slate is cheap and can be used for shielding. Also, we use Full Names here when posting; do fix that error.
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Rich Feldman
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Re: DEMO-FUSOR, How much can it take?

Post by Rich Feldman »

Hey Keelan,
You asked whether your bell jar can withstand vacuum of 30 microns inside.
By what factor is the stress greater than that on same jar with vacuum of 30 torrs inside?
Assume the external pressure is 760 torrs in both cases.

Not counting the risk of spot heating by electrified particle beams,
which could form at 30 microns and not at 30 torrs.
All models are wrong; some models are useful. -- George Box
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