My take on the Leyden Jar

I've seen lots of leyden jar instructables. My favorite is Kiteman's Be a Scientist: Bottle Electricity. I've made little film can jars for my little sister and she loves it.
But, be wary, I've seen one instructable that uses a photoflash capacitor or similar in the video to fake powerful "flying" sparks.

As the title says, this is how I make my leyden jars. These make nice, fat sparks. Once I finish my bonneti/sectorless wimshurst machine, I'm going to try out some 5-gallon bucket leyden jars. But, beware, these are DANGEROUS, like a loaded gun. They will KILL YOU if you arn't careful.
These smaller jars aren't deadly. But, they WILL be very unpleasant if you take a spark from them.
Anywhere, here's my take on the common leyden jar. Enjoy. =]

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Step 1: Parts list

Parts:
-Plastic container. HDPE plastic seems to work best, but I've found that thicker PP containers can work too. This will be the type of plastic container I'm using for the instructable.
-Aluminum HVAC repair tape. This stuff is used to mend air ducts, and also makes nice leyden jar coatings because it is already sticky on one side.
-A round-headed bolt/nail. The larger and rounder this is, the better. Don't select one too large, or the leyden jar might not charge. If you want to try a fancier top terminal, see this site, it has lots of info on leyden jars.
-Some metal bead chain or some copper wire. Whatever works for yah, though I like the bead chain more.

Tools:
Hot glue gun
You hands
Some patience
The will to start over if you get it wrong
Oh, and some way to make a smooth hole in the lid of your container. This is very important.

Got all that? lets get started.

Spedy (author) says: Mar 25, 2008. 1:23 PM

Update #2 HOLY COW! I just got a 2" spark off this thing after charging like forever. It was awesome.

cowscankill in reply to SpedyNov 19, 2008. 6:25 PM

Charged with what? 2 in is like... a lot of volts lol, forgot how much...

Arano in reply to cowscankillFeb 22, 2010. 2:27 PM

if i remember right its something like 1kV per cm spark through air but i'm not sure if thats right

Spedy (author) in reply to AranoFeb 22, 2010. 9:09 PM

30kv/cm for relatively dry air at sea level air pressure, IIRC. Interesting to see people are still looking at this old instructable..

Spedy (author) in reply to cowscankillNov 21, 2008. 6:02 PM

On that day, I charged it with regular old 3/4" PVP pipe, rough paper towel, and I think an old, cleaned sock over the paper towel. It was exceptionally dry in the air that day too.

Synn says: Sep 6, 2009. 6:48 PM

Can you charge these with the circuit from a disposable camera? I'm guessing so, I just haven't seen anyone else ask this question.

Synn in reply to SynnSep 6, 2009. 6:50 PM

It isn't important, i'm building a small VdG, will take about 30mins or so, i'm just wondering :P

ggiihh1 says: Dec 1, 2008. 2:31 PM

how exactly does one charge it??

Lance Mt. in reply to ggiihh1Jun 26, 2009. 5:23 PM

A old crt screen or tv works well as well. Takes the effort out XD

Spedy (author) in reply to Lance Mt.Jul 2, 2009. 8:36 PM

Might work for others, the TV/CRT's I have don;t seem to hold a charge that well. Turning it on the first time works, but on/off after that gets nothing..

Spedy (author) in reply to ggiihh1Jan 25, 2009. 3:06 PM

Re-read the last step. It tells you how.

Dr_Stupid says: Sep 18, 2008. 1:35 PM

okay go up there and edit your text: "They will KILL YOU if you aren't careful"...then you go to say "These smaller jars aren't deadly"... Any leyden jar is dangerous and has the potential to kill you. ALL Leyden jars should be treated as though they are fully charged.

the_burrito_master says: Aug 25, 2008. 2:07 PM

awesome I never knew they were built like this! a great way to charge this thing would to bring it to a mc' donnalds and put it next to a plastic slide when kids are going down. lol that might get you quite a spark.

GorillazMiko says: Mar 24, 2008. 3:25 PM

Cool! Great instructions, photos are amazingly clear, great job.

Spedy (author) in reply to GorillazMikoMar 24, 2008. 3:28 PM

Thanks! My camera was performing quite well today for some reason. I took several different versions of each shot, flash/no flash, longer exposure, ect and then picked the best ones. =)

Spedy (author) says: Mar 24, 2008. 1:52 PM

Update! That round top terminal is more important than I realized. This refurbished jar (the one shown in instructions) outperforms the water-filled one because of the smoothness of the bolt, and can store a spark almost an inch long! The other jar can, at most, get 1/2". Big difference.

I'll have to try graphite coated ping-pong balls like here some time...