In about 30 minutes after the Makerspace meeting on Tuesday, Ross, Jason and I made a Jacob’s Ladder from an old neon light transformer that I brought in, a couple pieces of wood, and some TIG welding aluminum filler rod.
With 110 Volts at its input, the transformer put out 9000 Volts! The arc formed across the gap, but it wasn’t actually a high enough voltage to make the arc ascend the ladder. When I hooked the transformer through a Variac and turned the knob to 130 Volts, the arc began to ascend the ladder – but only a few inches. The obvious solution was to add more voltage, so I hooked another Variac in series with the first, turning this one to 140 Vac. With the output of the transformer a bit under 12000 Volts, the arc ascended over 2 feet up the ladder. Check out the video below showing the arc’s interaction with wood.