Umm, where exactly is the new material here? Thiago’s fusor was all over the news (I think it was even on had) last year, and I know that Richard’s fusor-iii was on here from a long time ago (he built it in the 90s). The only new project is his fusor-iv is still in the parts gathering phase…

But regardless, fusors are quite impressive little toys. Congrats to all of you that actually got neutrons!

Posted at 6:26 pm on Mar 18th, 2007 by ...

That has to be the most freaky_scientis_experiment_thingy I’ve seen!

Posted at 6:31 pm on Mar 18th, 2007 by Morten

Mmmm.. plasma

Very cool! The 17-year old who made a fusion reactor also made it into PopSci’s How 2.0. If only it put out more energy than it took in…

A flyback transformer (see http://www.sixmhz.com ) would be handy for the HV source, you can get 18-20 kv from a 10v source using a KSE13009 transistor from Fairchild. Just watch out for radiation! Alpha radiation doesn’t matter here, but you need the equivalent of a sheet of plywood to stop Beta and Gamma radiation can be stopped only by lead sheeting or several inches of concrete. I recommend surrounding the chamber with lead flashing (get it from a hardware store, its used for roofing), except for a plexiglass window.

Also, where do you get deuterium gas from? I can’t find it in my local chemical supply store, and my highschool has only small samples. eBay? UnitedNuclear (if there hasn’t been another Delta-Force raid on their server)?

Posted at 7:12 pm on Mar 18th, 2007 by HaX80r

a flyback transformer will not give nearly enough power to get any detectable amount of fusion. The hobbyist community has developed a number of unique driver circuits which allow large amounts of power to be produced (the record is in the 50kv region w/o external multiplication, and about 200ma of current) but flybacks were not designed for high power so they only last a few seconds to a minute at >100w.

The cheapest place to get deuterium gas is to get some heavywater (D2O) and electrolyse it, but you also have to run the gas over some silica gel to dry the gas (water + high vacuum or high voltage = bad) Or you can ebay for a lecture bottle of deuterium, but you not only have to buy the bottle, but also a set of regulators, fittings, etc, which makes it a very costly few liters of gas.

Lead shielding is a good idea, but just about any fusor that will run at low enough pressures to actually fuse anything will need to be made out of nice thick stainless steel, which will block most everything except for a few very high energy gamma rays.

Posted at 8:20 pm on Mar 18th, 2007 by ...

You can buy Deuterium Oxide from http://unitednuclear.com/chem.htm and in the description it says, “Easily make pure Deuterium gas for Fusor experiments, etc.” so i guess if you want deuterium gas, you have to make it yourself. i looked on Ebay, and there is no deuterium gas for sale there. hope this is useful.

Posted at 10:06 pm on Mar 18th, 2007 by Josh

The Farnsworth Fusor is very easy to make. I’ve been working on mine for the past 10 months or so and am probably going to get fusion within the following month, pending the acquisition of a deuterium regulator and some other goodies.

http://fusion.wsyntax.com

Posted at 11:30 pm on Mar 18th, 2007 by cyanoacry

OMFG WHICH READ BUTTON DO I CLICK!?

Posted at 11:38 pm on Mar 18th, 2007 by Airmann

woah

I think I’m going to take my [everything i've ever built or designed] and go sit at the kiddie table and shut up.

we can’t repel hacking of that magnitude!

Posted at 7:03 am on Mar 19th, 2007 by strider_mt2k

why yes im going to rush down to my local electronics store and junkyard so i can build one of these this evening

Posted at 8:48 am on Mar 19th, 2007 by Apothus

ooohhh! fusion! May I ask if this fusion reactor produces energy!? like useful energy!? great proof of concept deal, but if I’m gonna sit down and build one of these, i wanna at least charge my laptop or cell phone off of it. As i understand it, with the REAL fusion reactor that produces useful energy, they can only recapture 30% of the energy they feed it, and the reaction lasts for just milliseconds. and ontop of everything else, gamma rays are so potent, i wouldn’t wanna be anywhere near any fusion reactor without litterally a ton or 2 of lead sheilding. Albit, walking a few miles down the street would be just as safe. And if I made one of these, i would start to shoot electrons into some beryllium, and that would shoot out nutrons that go into some graphite slowing them down smashing into some thorium turning it into U235, yes the fisionable kind. just goes to show you how dumb these terrorists really are.

Posted at 2:05 pm on Mar 19th, 2007 by Mouse

hey, chill out. these types of fusors are really nice for demonstrational purposes. Note, a good deal of nuclear science is a lot more like chemistry (mix thing a and thing b under the right conditions and get things c and d) and much less like omg we’re all gonna die!! its the bomb! the environment! ah!!! stuff the media makes it out to be.

no this type of fusor will not generate energy, although there was hope when it was first designed it could. it is however a nice source of high energy neutrons for further nuclear experiments.

while still too expensive for even most of the hacking/ hobby community to get started with nuclear physics, it is nice to see that some of the concepts pioneered in the big labs can be at least tested (if not worked further on) by the little guy. again despite what the media might have you think all our high energy physics comes out of the work of a handful of labs, cern, fermilab, slac, and much is relatively new and untested.

Posted at 2:55 pm on Mar 19th, 2007 by tillin9

I didn’t know that a flyback wasn’t powerful enough to start fusion, interesting.

Hey, to the previous comment:
If you could charge a cellphone off your fusor, you’d win the Nobel prize. People have been trying to do that for years.

About adding neutrons to thorium after slowing them with graphite… you won’t get enough pure U235 to do anything useful. You’d need about a pound or so to make a nuke, and thorium isn’t exactly cheap. Also, you’d have to separate the Uranium from all the thorium. Think calutrons and megawatts of power. Not fun.

Has anyone tried to affect the plasma in the fusor using fairly strong electromagnets? I don’t know if that would be useful, but it might be neat to have a sphere of plasma instead of a cloud. I’ll try to do so myself.

Be careful with that plasma y’all!

Posted at 3:16 pm on Mar 19th, 2007 by HaX80r

but dude, don’t forget, the more you operate one of these things, the more nutrons hit atoms and cause them to turn into isotopes, usually unstable ones. So i would imaging that this thing would get more and more radioactive just like the casings of nuclear power plants and that fusion reactor they trying to perfect. and may we not forget of all the undetectable sub-atomics, like nutrinos and pions and crazy shit. or does this thing have a bubble chamber on it!? that would be cool. btw, did they prove that a proton is unstable yet!? didn’t they have like millions of tons of water like 6 miles underground or something?

Posted at 3:26 pm on Mar 19th, 2007 by Mouse

wow

Posted at 7:42 pm on Mar 19th, 2007 by chris

From my limited poking around on the site, I see that author’s rev 1 set up was getting a vacuum down to “only” 20 microns (0.00026% of sea level) using a run of the mill electric air pump. Ah, but Mr. McDermott says that to get the ~1 micron needed to really get into the game can be acchieved with a two stage mechanical pump. No need to get into the oil diffu$ion or turbomolecular pump$.

I wouldn’t get too worked up about the steel chamber becoming significantly radioactive. Unfortunately, Brian’s decay curve xls data sheet from one of his experiments is offline, but I suspect the mass of all isotopes stays pretty low, even more so for long half-life isotopes.

Posted at 9:14 pm on Mar 19th, 2007 by Carl Holmberg

I think the fusor II is the coolest one there. It is the perfect addition to any tube collection. Also it looks like the easiest to build and a great addition to everybody’s living room, right next to the lava lamp. I may actually see if I can build one. . . on top of all of my other projects. Lets see, rewire my mercedes, megasquirt it, fix the turbo in the diesel, build a fusion reactor. Ok I think I got the plan

Posted at 6:58 am on Mar 20th, 2007 by paige

His 3 legged mutant children will be so proud. Scarry stuff.

Posted at 7:48 am on Mar 20th, 2007 by Wurx

@mouse: I seriously hope you’re being sarcastic there. in answer to your first and most serious point, no, large-scale fusion reactions haven’t reached break-even yet, and yes, they do produce a lot of gamma radiation and neutron flux. as these tabletop fusor designs are producing only thousands of fusion reactions per second, the amount of induced radioactivity in the vacuum chamber is pretty negligible. the “millions of tons of water 6 miles underground” sounds like a neutrino detector. i don’t have a clue what you mean by “is the proton unstable”.

Posted at 8:24 am on Mar 20th, 2007 by PKM

Hey fuk fusion try water cells, they harness the power of nature directly.

Posted at 1:54 pm on Mar 20th, 2007 by fuk_fU510n

^Wow. An energy troll.

Hydrogen fuel cells are all well and good, but produce nowhere near the kind of power you could get from a working fusion reactor. Furthermore, the energy to electrolyse the water into H2 and O2 has to come from somewhere…

Posted at 3:26 pm on Mar 20th, 2007 by Cynical Jawa

Hmm. Did this get posted somewhere outside the technological community (”ZOMG, crazy kid build fusion bomb, CLICK ME NOW” or something)? We’re getting a lot of dumb comments.

Pretty neat, though the farnsworth-hirsch fusor has been around since the 50s. If I had built one, I’d put it up on the mantelpiece with a viewing window so that people could see the little sparkles of plasma.

“yep, that there is nuke-yoo-lar fujen.”
“well, I be. that’ll show them commies…we got so many nukes that anyone ‘n his dog can build one these days.”

Posted at 10:09 pm on Mar 20th, 2007 by SL

What?! Playing with nuclear radiation is bad, real bad. I will get something else to generate power. I would put that in a concrete bunker and observe it using a CCTV I hate to be near that stuff! It is literally a Mini-Chernobyl! Nukes=Nasty

Posted at 10:17 pm on Mar 20th, 2007 by Aguiluz

Playing with rads is indeed bad, but these things produce *very* low amounts. Unless you stood next to one operating none-stop for about a fortnight, it wouldn’t exceed your annual dosage from other natural sources (minerals, radon gas, food/drink, cosmic rays…)

Posted at 12:59 pm on Mar 21st, 2007 by Cynical Jawa

sl, you are probably right- aguiluz needs to go and read about what chernobyl actually was, and read the article about this fusor and how they are not “literally” the same. never mind- maybe a few people will learn that nuclear experimentation does not necessarily = mutants and ecological disasters.

Posted at 1:59 pm on Mar 22nd, 2007 by PKM

“Mini-Chernobyl”? No, a fusion reactor, unlike a fission power plant, can’t spiral out of control and explode. That’s exactly the problem. Physicists can’t get “exploding” fusion reactions when they try!

Please, please take a basic course in Physics or Chemistry before damning all science.

Posted at 10:30 am on Mar 23rd, 2007 by Jon