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Help with Leyden Jar Answered

I have seen many of the instructables about building a leyden jar, but I built two and I cannot seem to make either of them work.

First I made the glass one. I filled it with salt water and stuck a long nail in through the lid because I couldn't fit my hand in to wrap it with aluminum foil on the inside. I sealed it well with hot glue and taped a very neat, crinkle-less strip of aluminum tape around it, the kind that is used for repairing air ducts. I tried charging it by rubbing around a fuzzy blanket on the carpet. That always produces a big spark, so while my brothers were rubbing their hair on the blanket and carpet, I was holding the metal tape around the glass jar with one hand and touching the grounded screw on the electrical plate with the other hand. When my brothers touched the nail on the top, we both felt a shock but when I tried to discharge it by touching my fingers to the nail and the tape at the same time, nothing happened. I don't think it is holding a charge at all.

Next I didn't touch the metal tape at all, and we rubbed our hair on the blanket and touched the nail. But when I tried to discharge it, the same thing: no spark. So I assumed the glass was too thick, so I made the plastic one. This is made out of a Tang powdered drink mix container, I cleaned it, filled it with salt water, and wrapped the inside and outside with aluminum foil, as tightly on the sides as I could. I used a smaller nail this time, but I attached it to the inside aluminum foil with a thin strip of foil. I sealed the nail up and made sure there were no leaks. I performed all of the same tests as last time, but still no results.

Can someone please help me figure out where i am going wrong? Thanks :)



Best Answer 6 years ago

When you try to discharge by connecting the inner and outer layers, you should try reversing the order you get hold of the contacts.

Alternatively, connect an insulated wire to the outer layer, and bend it over towards the centre contact, like this.

That a/c foil tape glue is non-conductive so you need to find a way to connect different layers metal to metal.


6 years ago

I am not sure about the differences between these jars and the "capacitors" I made, but I wrapped a 2 litter bottle in tinfoil (I tried the air duct stuff and it didn't work) filled it all the way with super super saturated salt water and put a big nail in it and it held a tiny charge. What is sitting at the bottom of your glass jar btw?

As far as I know it needs the inner metallic band as well. The nail should connect to this band inside, either a chain laid on the bottom or useing a conductive liquid like salt water.

The inner just needs to be conductive (the first jar-makers thought the charge resided in the water in the jar).