If you are interested in building this Tesla coil, I have compiled a very detailed set of plans. These plans are available for purchase and help me afford to build fun projects like this. To find out more details about the plans, check out the product page.
Ellery and I finished our static gap Tesla coil on July 10, 2011. You can think of a Tesla coil as sort of a lightning generator. It builds up high voltage electricity until it is strong enough to break down the air and then it is released as what appears to be a lightning bolt. Tesla coils are inherently dangerous because of the high voltages and currents required to get one to function well. What’s more is the longer you want the discharges to be, the more power you need the coil to output and so the dangerous it becomes. We decided to start relatively small for our first coil to lower the chances of one of us seriously injuring ourselves. Our primary transformer is a 15000 volt 30ma neon sign transformer (NST). This should give us an output power of 450 watts (15000 Volts * 0.6 amps). And it works great!
We built this coil using almost all parts from our local hardware store. After the build was done and it was all wired up we had to tune it by adjusting the spark gap size and the primary coil size. We found that 2 gaps and 9.5 primary turns is about as good as it gets, but that depends on some environmental factors. We get about 11″ long sparks this way. Here are some videos of the coil in action!
The sound is a bit fuzzy in the videos. I figure it’s from the Tesla coil causing interference with the camera’s audio circuit. It’s actually very loud in person. Here are some more great photos of the Tesla Coil.