Build A Fusion Reactor

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Picture of Build A Fusion Reactor
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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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.

adityayo637 days 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?

nerd747323 days ago

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

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)  Adrianhudson1 month 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.
ARahman1771 month ago

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

christensent (author)  ARahman1771 month 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)  ARahman1771 month 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)  ARahman1771 month 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?
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.
BenNBulids6 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)  BenNBulids1 month 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)  ARahman1771 month 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.

12010042 months ago

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

kodama2 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.

crob095 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

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

drslag3 months ago
you need an extremely high temperature to star the fusion process, as hot as a fission bomb
kodama5 months ago
Still in the early stages of researching this. Can they be modified to harness generated power?
buildyoung5 months ago
Hi, sorry if you get asked this allot but I am building a fusor (non demo already did that). And I was wondering if you could maybe post a schematic for the HV system. I am using the same method as you, a hand wound ferrite transformer (flyback) which will be fed through a CW to get a negative output. The transformer is powered by a zvs driver connected to a rectified 12 amp variac running at 36v. Thanks.
Nice Project I would like to give it a try myself. What inspired you to build this?
Can you give me an estimated cost to build what you did?
Also do you have to TIG weld the parts or can another type of welding work?
One last question what type of shielding other than the lead did you use?
christensent (author)  Nuclear_Ninja2 years ago
I was just looking for a science project online, found it, and it sparked my interest. I spent about $6000 on it, but it could be done for less with better planning. Yes, the parts need to be TIG welded. Other forms of welding are not completely vacuum tight. I used only lead. While it is possible to shield neutrons, it is extremely expensive and bulky, and isn't really necessary for the neutron levels produced by this device.
$6,000?!?! That's half my upcoming mars mission budget!
(I'm planning the launch for ~2015)
Not sure if joking, or if you have E.T. held hostage in your garden shed...
on what scale are you talking like what counts were you getting off the neutron detector?
and thank you for the information
christensent (author)  Nuclear_Ninja2 years ago
At peak run a typical home built reactor will make one to two million neutrons per second. This may sound like a lot, but it is very few from a biological hazard. You could stand a few feet from it for days with effectively no risk.
Ok what are you currently using your neutrons for or are you just running it for the sake of running it? and if you dont mind me asking are you in college if so what degree are you working on
christensent (author)  Nuclear_Ninja2 years ago
I was pretty much running it for the sake of building it, tweaking it, and having fun with it... It is possible for it to be used as a useful neutron source for experimentation, however I lacked sufficient equipment to do that stuff. I no longer run it since I am not at home. I built this in high school, and am now at college at MIT studying electrical engineering and physics.
ok and congrats on the MIT thing I an studying nuclear engineering at nc state. hints at my intrest in a reactor. thank you for all the information. If I end up building one of my own I will post pics.
Once again thank you for the info
crabcookies6 months ago
I am a high school student interested in making this or something similar and I was wondering if the chamber has to be stainless steel? Is that just so it doesn't rust or for another reason?

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