Couple of questions

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steventw
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Couple of questions

Post by steventw » Mon Jun 25, 2018 10:11 pm

Hi

I got my vacuum chamber that going to use and pump
Parents wanting plenty of safety features
So wondering where could source some lead sheeting from to make a box for chamber to go in for neutron absorption
And what would a faraday cage be good to make out of for any chance of lightning discharge to ground it

Hope can help

Thanks

Steven

Jerry Biehler
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Re: Couple of questions

Post by Jerry Biehler » Tue Jun 26, 2018 4:04 am

Roofing suppliers might have lead sheet.

You dont need a faraday cage, you are not working anywhere near the voltage that would require one.

steventw
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Re: Couple of questions

Post by steventw » Tue Jun 26, 2018 4:07 am

Ok thanks will look into it

ian_krase
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Re: Couple of questions

Post by ian_krase » Tue Jun 26, 2018 8:25 am

Personally, I STRONGLY recommend that you put plenty of work into excellent grounding. Get some thick-ish copper wire and connect all the things in a star network.

Even if you don't have an actual faraday cage, making sure that you'll inadvertantly touch or get neara grounded conductor rather than a hot one is a good idea. As well as making sure that grounding can't fail due to plugs separating.

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Dennis P Brown
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Re: Couple of questions

Post by Dennis P Brown » Tue Jun 26, 2018 7:58 pm

Neutrons are not stopped by lead shielding at all; rather, light hydrocarbon material like paraffin will stop neutrons but most fusors produce very few from a health stand-point.

Lead or slate can be used for X-ray shielding. I use slate since it is non-toxic and non-conductive - cheap and easy to obtain and cut. Available at any home depot. These materials can stop the x-rays that a high voltage system can generate (when operating over 20 kV.) One must calculate the thickness using the max voltage your system will have.

Agree with Ian that good ground system is critical for safety as well as using proper high voltage cable (i.e. correct voltage rating)! Valid grounding is absolutely necessary so one does not 'float' their chamber making it develop a lethal potential.

MatthewL
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Re: Couple of questions

Post by MatthewL » Wed Jun 27, 2018 3:25 am

A box is not really necessary. you could just build a single square "plate" about 12" X 12" with hydrocarbons and some lead or slate. This will create a shadow cone shield which should work great. Check the FAQs to find more information.

-Matthew

steventw
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Re: Couple of questions

Post by steventw » Wed Jun 27, 2018 4:15 am

Thanks for advice

Got my vac chamber and pump and magnets for idea
So far cost about 1900 AU

Going to be getting a 30v 10A lab grade power supply from eBay next pay
Hopefully is enough to create plasma

Just need to modify vac chamber for power in and gas inlet for hydrogen and build housing for magnets

Will look into the light hydrocarbons/slate

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Richard Hull
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Re: Couple of questions

Post by Richard Hull » Wed Jun 27, 2018 4:55 am

I don't think a 30v supply will create a plasma. 30kv @10 ma will. (30,000 volts @ .01 amps)

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
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Dennis P Brown
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Re: Couple of questions

Post by Dennis P Brown » Wed Jun 27, 2018 11:42 am

Just creating a plasma requires a few hundred volts, at least; however, you indicate you are interested in real fusion. If that is the case, getting a power supply that can do over 20 kV is required and very likely near 30 kV. But voltage isn't all one needs - the power required for detectable fusion is around 200 watts (higher, is better.) Getting a power supply that can achieve both these levels can be difficult and expensive. Also, these are lethal power supplies. Read the FAQ's on this subject and read what others have done in the past.

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Rich Feldman
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Re: Couple of questions

Post by Rich Feldman » Wed Jun 27, 2018 3:43 pm

Please keep us informed of your progress, Steven.

30 volts is plenty to make a plasma, with plasma current up to about an amp without damage,
if you have a hot cathode. Common in mercury vapor rectifiers like the 866 type.
A forum search found some old presentations here.
rallcr.JPG
rallcr.JPG (13.71 KiB) Viewed 1874 times
With a suitable dropping resistor, the same DC supply can power the rectifier filament.
Richard Feldman

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