Build A Fusion Reactor

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Yes, you can build your very own nuclear fusion reactor in your house! But first, a few warnings:

-This project includes lethal voltage levels. Make sure you know your high voltage safety or have a qualified electrical advisor.
-Potentially hazardous levels of x-rays will be produced. Lead shielding of viewports is a must!
-Deuterium, an explosive gas, will be used. Make sure to check for fuel leaks.
-All the other inherent dangers of a home engineering project of this degree (a wide gamut of potential injuries, damage to the checking account, and the loss of general sanity)

Here are the minimum required materials:

-A vacuum chamber, preferably in a spherical shape
-A roughing vacuum pump capable of reaching at least 75 microns vacuum
-A secondary high vacuum pump, either a turbo pump or oil diffusion pump
-A high voltage supply, preferably capable of at least 40kv 10ma - Must be negative polarity
-A high voltage divider probe for use with a digital multimeter
-A thermocouple or baratron (of appropriate scale) vacuum gauge
-A neutron radiation detector, either a proportional He-3 or BF3 tube with counting instrumentation, or a bubble dosimeter
-A Geiger counter, preferably a scintillator type, for x-ray detection and safety
-Deuterium gas (can be purchased as a gas or extracted from D2O through electrolysis - it is much easier and more effective to use compressed gas)
-A large ballast resistor in the range of 50-100k and at least a foot long
-A camera and TV display for viewing the inside of the reactor
-Lead to shield the camera viewport
-General engineering tools, a machine shop if at all possible (although 90% of mine was built with nothing but a dremel and cordless drill, the only thing you really can't build without a shop is scratch building the vacuum chamber)
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adityayo634 days ago

What valve do you recommend for the one between diffusion pump and vacuum chamber? I've looked through ebay and leskers but I couldn't find a kf flanged gate valve that is bellows sealed under $150. Many on recommends a gate valve that is bellows sealed but it is way too expensive.

DATCAT2 months ago

so you need a high negative voltage instead of a positive like static or high positive like what come out of a MOT,flyback,igntion coil

baecker03 DATCAT2 months ago

fly back wouldn't work, and he is specifying that 40kv be used

DATCAT baecker032 months ago
Then want can you use a microwave oven tranformer
or a car igniting coil
christensent (author)  DATCAT21 days ago

Microwave transformer is less than 10kv. You can sort of make series stacks but you have to really know what you're doing and it gets extremely dangerous. It's a poor solution. Car ignition coil won't put out enough current, that is designed for pulse duty.

JoshWolff727 days ago

I am really interested in this and would love to build it. Is it possible to hook this up with thorium instead of deuterium? How can I simplify this project? Is this fusion reactor hooked up to a capacitor or something of the like that it charges - how is the power harnessed?



christensent (author)  JoshWolff721 days ago

No thorium, can't really be simplified much, no capacitor, and no power harnessing

christensent (author) 21 days ago

I wrapped lead over it in such a way that there is lead between me and it

ARahman17721 days ago

how did you shield the viewport with lead exactly

adityayo633 months ago

What are the health risks involved in this experiment in regards to neutron radiation? Are there any ways to prove that you were successful in fusing atoms together and avoid neutron radiation?

christensent (author)  adityayo632 months ago

There are no risks to running this device, the amount of radiation is incredibly tiny. If you're worried about it, stand across the room. Radiation falls off 1/r^2 in this case.

um i`m trying to be posive here you Die . The is a way to slow it down and then get asobed by lead ( a tipe of plastic ). :L sorry I cant be more helpful.

or water but you have to be carful!

I can't find a spherical vacuum chamber anywhere for under $500. I searched eBay and a few other sites. Anyone have any ideas where I can get it from? I do not want to go through the trouble of making one.

find a machine shop?

Adrianhudson3 months ago
Two questions.

One- would a deeper vacuum be better for this experiment if possible?

Two- would putting more power into the reactor also increase the amount of fusion? So instead of 40kv maybe 100kv would be better?
christensent (author)  Adrianhudson3 months ago
1) Yes, but with rapidly diminishing returns because you backfill it with deuterium up to a few microns anyways. The pressure you obtain before backfilling just allows the deuterium purity to increase.

2) Yes, very much so. More voltage at same power is more fusion, and more power at same voltage is more fusion. More power at more voltage is even more fusion.

if you have the money and know how to get 100kv and proper insulation.

Would There Be A Chance Of It Working, If It Was Built On A Bigger Scale, And Would It Be Able To Power A Ship That Has A Maximum Speed Of 5000 MPH.

nerd74733 months ago

This is very interesting I was wanting to make a plasma fusor

ARahman1774 months ago

Would an air diffusion pump work instead of the oil diffusion pump or would it have to be oil or turbo?

christensent (author)  ARahman1774 months ago

I don't know, not familiar with that. If it reaches similar pressures and pumping rates as an oil diffusion pump, sure. I think that might be for higher pressures though.

when you say at least 75 microns do you mean anything below it...would a 25 micron vacuum pump suffice?
christensent (author)  ARahman1774 months ago

75 microns would get you a demo fusor, but no fusion. You really need a pump that will get you <1 micron and then you backfill with deuterium up to about 10 micron to run. And a super nice mechanical pump that says 1 micron will not work since that is an ideal measurement, and also it has no pumping speed at that pressure.

thanks for the info...where did you get the two pumps that you used in this reactor?
christensent (author)  ARahman1774 months ago

Ebay... just about everything for a project like this will come from ebay unless you have tons of money to blow on nice new stuff

What roughing pump did you use in this reactor

I have already built this demo fusor:

Can I just hook up a deuterium leaking system and a neutron detector and have it work? Or will I need something more?
BenNBulids9 months ago
What vendor did you get the Deuterium from. I am having troubles as most do not ship to residencies. Thank you
christensent (author)  BenNBulids4 months ago

It takes luck to get it from a big company. Keep trying, and eventually you will succeed. I had better luck going to specialty gas locations of the big distributors as opposed to calling them.

If you are still trying to find Deuterium, try

Where can I get some deuterium gas? It wasn't there on United Nuclear.

You would be able to buy Deuterium Oxide (D2O), and use electrolysis to seperate the Deuterium from the Oxygen

christensent (author)  ARahman1774 months ago

Yes, this works fine and is how I first started out getting fusion. It is very hard to get good purity though. If you want high performance, you'll really want to source the gas in a cylinder.

12010044 months ago

wouldn't you want to get some energy out of it by heating up water and running steam through a turbine

kodama5 months ago

Has anyone tried to measure the photons produced? I'd have thought this was the obvious area to research to energise/commercialize the project.

crob098 months ago
Maybe a dumb question but how's a Fusion-Reactor used to produce electricity, isn't it threw steam generation?
If it is, the how can the Reactor be deemed efficient, or is efficiency in this case a measurement of something else?

Very cool project!!!

This reactor has a massive net loss of energy. It doesn't have much of a use other than having your own star :)

What are the products and byproducts of this machine?

And for what things can we use this, where an we practically use this?

Plz reply

What are the products and byproducts of this machine?

And for what things can we use this, where an we practically use this?

Plz reply

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