there was another! some kid on the Ars Technica forum liveblogged his attempt. notable highlights:

how it started

I melted a large hunk of uranium out of one side of an ore chunk and it is by far more radioactive than anything I have (gamma). I am however concerned that background radiation level in my office and bedroom (next door) have almost doubled. I will measure again tommorow and see if maybe it is something cosmic related.

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HOLY FUCK. DO NOT IONIZE OR VAPORIZE URANIUM. IT IS A HEAVY METAL. It's not the radiation that will kill you. It's the fucking heavy metal toxicity. Here's some guidelines for safe handling.

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I am no David Hahn and am not as stupid, but I HAVE built a functioning breeder Aluminum+Lead sheild, but some radiation is escaping. I am going to beef it up. Right now my office is at 15-25 CPM on the counter (my dosimeter has not arrived yet) and my adjacent room is 6-10 CPM on the counter. This is over the course of 3 days in my configuration. From top to bottom. Am-241 at 2uCi bombarding a thin aluminum sheet (thicker than foil) moderated by a combo of water and paraffin, another aluminum plate to further slow the neutrons down and a crushed pile of U-238 ore (reduced with high strength peroxide). This is enclosed in a inch thick lead shield. Call me crazy if you must.... I am currently as I type, evacuating an old gas laser tube. We'll see what happens. I have Thorium and some U-238 coming in so I will be building a concrete containment block this weekend.

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got that shit wrong. I am breeding plutonium 239. I got it messed up.

on purpose

So you're breeding fuel for nuclear weapons? that's what i thought. you're breeding pu239, which means you're breeding pu240, which is a poison. i have not given much thought to how to avoid this and change the reaction to breed something less poisonous, since you have no use for the 239 beyond "dude, i'm breeding weapons fuel!"

I am not breeding it for that purpose. Actually, I dont believe I have stated my purpose, so let me inform the fools here that may think I am breeding weapons useable fuel.I am breeding this material for its HEAT. U-238 is way too long lived to decay in a manner in which would create any sort of viable heat source for use in a seebeck electric generator of my own design. Now take off the tinfoil and shoe covers and get a grip.

some developments

The gamma output just sharply dropped so something must have changed rapidly. I am just now researching what is going on so I am not quite sure yet what happened. I think I am going to pull the neutron moderators out.

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not great, not terrible..

Current results for the test dosimeters. 1)Reactor dosimeter - 60 roentgen 2)Desk source - Broken 0-R 3)Personal source (which I had as I slept in the next room) is reading 22 roentgen.

You mean microroentgen... right? Or milliroentgen? Surely not full on roentgen?

Full roentgen.

I'm out of my area of expertise here, but according to Wikipedia, the average lifetime dose is 16R. Is there not some danger in exceeding that amount currently?

Yes, I saw that. Yes, I am concerned a bit. I havent put my reactor into the large concrete containment yet so I guess it is definately time to do so. I have no symptoms of radiation poisoning though...

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Okay, lesson learned... My equipment is giving me shit readings, or was anyway. Realizing my CDV 715 was shit, I removed the dial from it and attached it to my DSRB88. I based the readout circuit I built on a similar circuit that uses the same GM tube, so I know it is fairly accurate and also uses the same guage. The background radiation level in my office with the reactor is about 30 uR/hr. So, If I had the money, I would get myself a CDV-700, but I do not so I will just have to make due with this. SO I AM NOT DYING AND NEITHER IS ANYONE ELSE.

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A much better picture of the tube. I finally calculated the emmissions from this puppy to be 6mR/hr. I was hesitant to get my face so close to it, but for the sake of pics

the inevitable conclusion

so...the FBI just came... Yes, with the NRC and Texas health department...raided my home. They accused me of acquiring the materials to construct a dirty bomb. They refferenced the capacitor on page one that makes a quip about it looking like a pipe bomb. They also told me that arstechnica is under constant surveillance for things such as this. I mean, terrorists post thier research online all of the time.

Well, on the bright side, you now have some pretty accurate readings of the radiation.

Yeah, but iirc that kid had to have his house declared a hazmat site and he may have seen some juvie time, I don't remember all the specifics

That guy was a moron.