Coil Gun Speed Meter

October 1, 2009 by Caleb Kraft 28 Comments

_DIY_bullet_speed_meter (Custom)

One of the best parts of building a coil gun is seeing just how fast you can get that slug to move through the air. [Daniel] built this speed meter to be able to see exactly that. It is comprised of two optical sensors, one at each end of a barrel. As the projectile passes them, its speed is calculated using an Atmega16. Since the distance between the sensors is pre determined, its only some simple math to figure out the speed of an object passing between them. The result is then displayed on a nice looking blue LCD.

If the blue accent lighting and acrylic stylings look familiar, that’s because we’ve seen [Daniel] before. He’s the one that built the portable coil pistol.

[via HackedGadgets]

FIELD A Fluorescent Array, Wirelessly Powered

April 10, 2009 by Caleb Kraft 73 Comments

richard-boxs-light-field

What would you do if you were driving along the highway and you glanced into a field to see a giant array of fluorescent tubes lit wirelessly from the electromagnetic fields of power lines. Back in 2004, [Richard Box] set up this display after hearing about a friend playing “light saber” with fluorescent tubes under power lines. The tubes can be lit pretty easily by have a variation in voltage between the ends. By sticking one end in the ground and the other up in the air, he’s harnessing the strong magnetic field from the power lines. Though some thought the display was made to bring people’s attention to possible hazards of living near the lines, [Box] states that he did it just because it looked cool.

[via io9]

Making A Rail Gun

March 20, 2009 by Caleb Kraft 17 Comments

rail

[Rp181] has documented his entire rail gun build. He takes us through collecting the materials and assembling the system. It required 18 400V 3900uf capacitors to get the 5600 joules he wanted. It looks pretty impressive, though a video of it wreaking havoc on something might have been nice. We’ve seen rail guns before, from tiny ones for a robosapien to larger projects very similar to this one. In his instructable, he touts this as a “green” system. The capacitors are aluminum and no gun powder is required to move the projectile. Anyone want to do the math to figure out if it really is any better? Maybe if he’s collecting his energy via a giant solar panel.

[via instructables]

Leyden Jar Of DOOM.

January 24, 2009 by Caleb Kraft 14 Comments

layden

A leyden jar is basically just a simple home made capacitor. We’ve shown you how to make them before. This, however, is how you make a ridiculously large one. [Nickademuss] used a five gallon bucket to make his leyden jar. That’s five whole gallons of lightning. The video, which you can see after the break, shows it light up the entire room when it lets out a fairly formidable spark. This is dangerous folks, be careful.

Continue reading “Leyden Jar Of DOOM.” →

High Voltage Cable Inspection

January 14, 2009 by Strom Carlson 27 Comments

high-voltage-woker

Have you ever wondered how they inspect high voltage cables without taking them out of service? Check out this video which offers a glimpse into the life of a professional high voltage cable inspector. There are parts of the job you’d expect—namely perching on the cable like a bird, trying to not fall off—but the part of the job you wouldn’t expect is the suit. This suit is made of 75% Nomex, to prevent it from catching fire, and 25% stainless steel thread, turning the suit into a wearable Faraday cage. Of course, because he’s got a Faraday cage mere millimeters from his skin, the cable inspector spends his workday surrounded by half a million volts. To avoid electric shock, he equalizes the voltage potential between himself and the line before touching the cable.

Depending on your specific phobias, this video might make your job seem really dull… or really really safe.

[via Gizmodo]

Jacob’s Ladder

December 30, 2008 by Caleb Kraft 28 Comments

jacobs_ladder

[jandgse812] shows us how to build a Jacob’s Ladder from mostly household parts. The bulk of the instructions for this project are included in the downloadable document, there is a downloadable video as well. Be sure to follow to the end where he shows us a much safer and possibly better looking revision. The Jacob’s Ladder has become standard fair for any mad scientists laboratory. If you plan on having a workshop suited for world domination, it absolutely must have one of these in it. Be careful though, the high voltage can be deadly.

900,000 Volts At Your Fingertips

December 17, 2008 by Caleb Kraft 14 Comments

[Nickademuss] has put together these great instructions on how to build a 900,000 volt Van De Graaff generator. For those unfamiliar, Van De Graaff generators produce massive amounts of static electricity. They are usually the things you see in science centers that make people’s hair stand on end. [Nickademuss] put a lot of effort into this, he created 3D models and diagrams for many of the steps and gave a very detailed step by step breakdown.