Jonathan Warren

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Jacob's Ladder

Fall 2019

There's no better way to tell the world "I like electricity" than by making your own Jacob's ladder. It's actually pretty straightforward, once you figure out some of the nuances of high voltage.

This started out as just messing around with 10kV. I quickly learned you need to insulate the exposed conductors as much as possible, after I shorted out a supply by not realizing it was quietly conducting through 2 inches of 2x4.

FirstArc     SneakyBurn

With some trial and error out of the way, here's all you need to get a simple Jacob's Ladder made. I cannot stress enough how careful you need to be when working with anything other than low-voltage. Always test in an area without anything flammable, and always stay far away when you switch it on!

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The custom part of this project is creating a container of some sort that keeps the copper tubing insulated and physically secure. In my second version I 3D printed a very simple box with holes in the top and back to allow the copper tubing to enter the back (spaced about 3 inches apart, which seems to be enough air-gap) and exit the top (spaced about 1.5-2 inches apart). After I fed the tubing in (ensuring each piece is as far apart from the other internally as possible) I just dumped the tube of caulking into the box (fancy people may call this potting) and gave it a couple days to dry.

The other tricky part is getting the tubing in just the right shape for the ladder effect to work. You want to try to make an hourglass shape, bringing the two tubes a little less than a half inch apart. This allows a strong arc to form in the place of least resistance (smallest air-gap), where the arc will warm up the air above it and get sucked upwards. You want the tubing to pull apart after that pinch, but I've found that a V shape doesn't work - you only want the tubing to separate to a bit over an inch apart and roughly stay that way for the arc to stay strong as it moves up. This is something you have to play with (again, CAREFULLY!) and will definitely be unique to the parts, materials, and sculpting you do.


Such a satisfying sound!!