Time: 9 months
The current flows into what Flickenger calls the “hockey puck of doom”—an end cap of PVC pipe filled with silicone. Inside the gun, a transformer from an old television and additional circuitry repeatedly doubles the current and then pumps it to a capacitor bank. When the six capacitors hold 20,000 volts, the gun starts firing. All that electricity still blew a few pucks, so Flickenger recently tested a mixture of silicone and hexagonal boron nitride that draws away the heat, preserving electrical components.
Once the electric current reaches 20,000 volts, it’s powerful enough to jump the gap between two tungsten wires inside the aluminum gun. Flickenger couldn’t find a housing strong enough to handle such a powerful spark, so he built his own out of heat-resistant porcelain. He also affixed a fan from an old computer server at one end to help cool the spark gap.
After jumping the gap, the current runs into the primary coil, eight loops of high-voltage insulated wire at the gun’s nose. The coil induces a current in the secondary coil, a piece of plumbing pipe wrapped in copper wire. The current flooding the wire creates a magnetic field, which induces an electrical field inside the doughnut-shaped aluminum ring at the gun’s nose. This field generates streaks of blue lightning. For the most part, Flickenger operates the gun in his lab with the lights off. It can go for about 30 minutes before it needs to cool down. “When it’s running, it makes the whole room smell like a thunderstorm,” he says.
The gun generates a lethal amount of current, so Flickenger typically sets it on his workbench instead of holding it himself. He grounds the device by clipping insulated high-voltage wire to the aluminum shell at one end, then to a nearby pipe or, if he’s outside, a metal stake planted in the soil. This ensures the current won’t run through the aluminum shell and into the inventor. “You don’t want to be the fuse in that circuit,” he says.
WARNING: We review all our projects before publishing them, but ultimately safety is your responsibility. Always wear protective gear, take proper safety precautions, and follow all laws and regulations.single page
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.