Low Cost Jacob's Ladder Made From A Salvaged Oil Transformer

Step 7: Gee Mr. Wizard, Why Does It Do That?

Well, I'm glad you asked. Electricity follows the path of least resistance, which is why it starts at the bottom where the wires are closest. The arc is very hot, so it heats the air above it, make it more conductive. The arc moves up to that more conductive area, heating the air above that. It does this continuously until it gets to the point where the arc to just too long. At this point, it starts over at the bottom.

If you're going to have this on display, you should build an enclosure to keep people from touching it. I didn't go into how to build an enclosure, you can figure that out yourself and write your own instructable about it.

Comments

[waldosan]

insanely good article, i just found out a few days ago that i have quite a few of these sitting next to the furnace in my house. i think i'll wait till spring comes to really play with them. quick question, would it destroy them if i connected them in series I.E. connecting one transformer's HV leads to the primary of another transformer?

[crazy-blender]

yes it would destroy them if you connect them in series the primary of the second would burn up

[bloomautomatic]

I don't know if it would destroy it, but the outcome would probably be bad. With a 10,000 volt output and 120volt input, that's a ration of 83:1. If you put 10,000 volts on the primary, it would be trying to put out 830,000 volts. At the same time, the amperage going in is very low, so the outgoing amperage would be reduced by a factor of 83. That's the theoretical part. In the real world, I suspect it either wouldn't have enough amperage to actually make the voltage on the secondary, or if it did, the insulation would start to fail.

I don't know for sure since I've never done it, but I wouldn't try it.

[tinyrunninger]

i have been wanting to build one of them for years thanks for your input

[Nicademus]

I touched one of these just as it was being powered up..... Oops. Luckily I was seated and also fell away from the device. All in all, on the scale of suckiness, I'd rate that experience a 9 out of 10.

[rohang]

Tip: don't touch.

[Koil_1]

Great Instructable. Keep up the good work!