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Hmmm. I wonder how long it will be then until the guys at powerlabs give this one a shot.

Er... probably awhile.

Meanwhilst, they have some pretty cool videos.

In 1945, with the invention of the Leyden Jar (the first type of capacitor ever developed, invented in the University of Leiden, Netherlands)

Incidentally, "Removing any material from this site for display without consent from its author consists in an infringement of international copyright laws and can result in fines up to $50000 per infringement, plus legal costs." Oh dear, I shall be in debt now!!

Granted, it appears to have occurred as a result of a malfunction (too short a burst -> mild projectile vaporization), but -- hey, you can't have everything!

Granted, it appears to have occurred as a result of a malfunction (too short a burst -> mild projectile vaporization), but -- hey, you can't have everything!

Okay, I wear a trench coat, I was just as alienated as the next teenager, but I find this picture a little troubling. Sam Barros lives in Michigan now, and if you saw Bowling for Columbine you know what that means - all the other children are armed too. Teenagers with guns bother me, because my Mom TOOK MY GUN AWAY - I mean, because it's dangerous.

It's not how long you lived, it's HOW you lived...

I felt the same way when I was his age :)

Seriously; there are physiological changes that occur, alterations in brain chemistry, which, let us face facts, impair the judgement and good sense of young people. That is not to say that there are no teenagers with far better sense than the average adult; but even so, it's a stage in neurological development that does not promote sensible behavior.

It also means that explosions are not nearly as cool as they seem when you're 18. Another fact - chicks do not dig explosions. I learned this the hard way so now I pass it on to the younger generation.

I don't think explosives chemistry is a good starting place for a junior chemist; Sam Barros has obviously done fine, but I'm not sure how this stands as a role model. For one thing, he clearly does have good sense (note the many safety warnings emblazoned all over his web page.)

Chemistry involving dyes, optics, visual effects, material science and metallurgy (electroplating, for example) is no more difficult and much safer. Making stuff like this can't indulge your inner pyromanic like a bomb can. I'm not trying to criticize teenage boys for wanting to cause some damage - I certainly did - but it worries me.

So, I wonder - why does the slashdot story focus on the explosives? His EM devices are cooler anyway.

Ah, the hell with it. I'm only 23 years old! What am I thinking? It's time I put together a web page on how to weaponise biological and chemical agents. Now THAT would earn you some attention at the science fair.

Finally - when blowing up your school, wear ear protection! Regrowing fingers and toes is just around the corner (well, hopefully, I have some friends working on this); regrowing your inner ear may never be possible.

Evidently he's finished high school, since this page is a link to his IB extended essay project, which is done during one's senior year of high school. Unless something went horribly wrong with the project and he never graduated... :)

Hi, this site is all about Powerlabs, REAL POWERLABS. This site is awesome. My name is Sam Barros and I can't stop thinking about Powerlabs. These guys are cool; and by cool, I mean totally sweet.

This was already mentioned in one comment, but it was in a reply to another comment WAY down the page.

For REAL potato-gun/homemade cannon fun, Check out Sam Barros' PowerLabs cannon research page, which includes photos and videos of some amazing fun.

I've always had problems with the gas grill spark-maker not generating a strong enough spark. A Coleman flint-and-steel lantern lighter is a very reliable spark maker, and is perfectly designed for installation in a potato gun. When you drill the hole to install it in, make sure you seal the edges securely around the lighter, or you'll burn your fingers with escaping gas.

For even more dangerous experiments, check out this guy's page.

Conventional bullets go faster, nearly always, and are cheaper and easier.

See powerlabs, http://www.powerlabs.org/. Amazing hi-power electrical and other interesting stuff.

The video of projectile perforating a can with speed of 240km/h is here:
coilgun.mpg

If you want to see a powerfull gauss gun in action or make one, go to:
PowerLabs Gauss Gun Research.

Check out this link http://www.powerlabs.org/gaussgun.htm for the apparently largest Gauss Gun project on the web. Apparently it shoots with a speed of 774 km/h. Just a bit more and the projectile will break the sound barrier.

Here are a few different Gauss Guns, including the one from Half Life!

Yes, I did just pilfer these sites from Google, but didn't see any other references linked so far, soooo.....

First of all, there are no pictures of a gauss gun, because it doesn't exist yet. I have the parts for an inverter to charge it, but have not yet assembled it. Not having had much experience with switch mode power supplies, I'm just hoping it doesn't burn down.

For someone else's (working) effort, check out powerlabs.org

As to those who think car capacitors, etc might be better, they have a very low voltage rating (eg 15V). E=0.5*C*V^2, so even with a farad the energy isn't that great. Secondly, they are made from *thin* foil and have crappy current ratings, not much good for generating 10kA for 1ms. These are photoflash-rated caps, intended for 1ms discharge times - thick foil, good dielectric and some actual quality control.

Lastly, the capacitors will have to discharge through an inductor, even if it is only a couple of turns. Lack of voltage means the current rise is too slow (dI/dt = V/L) and so a low voltage, high capacitance bank will not discharge fast enough. Slow discharge means the ring has moved away before it receives much energy.

I'm also missing large silicon devices to actually discharge the thing. SCRs that can handle 10 or 20kA are not common and seem to cost many hundred of dollars. If anyone's got a spare one, please tell me! Otherwise I will have to make do with lots of smaller devices from surplus shops and build it multi-stage with messy triggering.

As for energy, consider 0.5*m*V^2. Given about 3 to 5kJ and about 2g of mass, you figure it out. It will be lucky to get 1% efficiency, but still. If it works well, I might have to look into firearms licensing. Big deal.

To those who say "you're a dickhead, that's lame", well, fair enough. Its not for everyone, and this page wasn't put up for the express of having it critiqued by /. bottom-feeders. I guess you could say "that's just sad", but if you're not an eleceng then you're not going to get what's interesting about this stuff.

No pictures/videos at the site mentioned in the article, but here's a different site with videos of a capacitor-powered gauss gun in action:

http://www.powerlabs.org/multistagecg.htm

Sam Barros has used a beer glass to contain his plasma.

My experiment using a glass jar

The problem when you don't use something to contain the plasma in the oven is that it can get sucked throuygh the vents by the fan, or sometimes it floats near the magnetron and destroys the mica covering.

Someone reassembling their microwave
Sam's site with his remounted magnetron he has used for making plasmas
I can't find the Hootenanny site right now, but it used to detail the contruction of a DEW with microwave parts and a horn. They used to upset the operation of some computers.
Slava's site detailing the use of a magnetron, capacitors and horn to make a HPM

. . . about 'Gauss Guns' can be found here