DIY Capacitor




Introduction: DIY Capacitor

In this Instructable I will be making one of the easiest high voltage capacitors that I know of.....

WARNING High voltage electricity can cause death and serious injury.I do not recommend that anyone work with high voltage power sources unless they know how to do it safely.

Step 1: Getting the Materials

You will need:

1.A long screw
2.Some tin foil
3.A 2L bottle
4.some salt and hot water
5.Electrical tape

The first thing you do is get the cap and put a big screw in it.

Step 2: Tin Foil Time

Now take 15inches of tin foil and fold it in half :)

Step 3: Almost Done!

Now tightly wrap the foil around the bottle and tape it in place.It is very important that it has almost no air bubbles between the plastic bottle and the foil.....

Step 4: That Wasnt So Hard Was It? :)

Ok ... Now if you want you can tape a wire to the foil and then wrap the whole bottle in electrical tape (thats what I did)

Fill the bottle with water and over saturate it with salt,baking soda
(Right now I'm trying water and vinegar 50/50 mix)


These capacitors work great in small Tesla coils and they make a very loud noise

Have fun and be safe



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340 Discussions

If you really want to make something REALLY dangerous manufacture a few capacitors utilizing 55 gallon poly drums with the entire outer surface covered with heavy duty aluminum foil very similar to this arrangement then sprayed with truck bed liner for insulation. Use a 30 foot coil of 1/2" soft copper tubing for your internal terminals for some major current carrying contact area with the 55 gallons of super saturated saline solution in each of the 2 barrels. Pick up a 500 foot roll of 12 awg copper wire and strip it with a sharp blade by tying off one end and walking down the line while holding the blade at the appropriate angle to efficiently remove the insulation at a decent pace. Wrap 5 50 foot lengths of your now bare 12 awg wire around the exterior aluminum foil covered drums in a helical ascending fashion then twist the 5 tails together tightly for a good 4 inches or so to produce a connection point with some respectable high current carrying capacity. 50 pound bags of water softener salt can be purchase extremely cheap to produce your SS salt solution. The roll of 12 awg wire costs $59 at lowes, the 60ft roll of copper tubing costs $139 and the salt somewhere around $10 bucks per 50lb bag. If you can scrounge up the poly drums free you can assemble a pair of far beyond lethal terminator caps for under $250 bucks! Charge them up with a pair of old 1500 watt microwave oven transformers (The good ones back when they were still called Radar Ranges) and you could set up a truly maniacal active burglar alarm system! Salvage the high voltage diodes from the microwaves as well of build a full wave bridge rectifier from high voltage diodes to make use of both ends of the AC cycle, waste not want not. Now simply run one wire to an expanded steel mesh fronting as an innocent a door mat and securely fasten other to the doorknob with the activation/detonator switch installed inside the door jam set to fire it off should anyone try to slip a credit card through the door jam to circumvent your lock. With one barrel charged positive and the other charged negative for a 16,000 volt DC combined potential difference at that capacity the perp would most likely explode violently when his now airborne corpse was determined to be the path of least resistance for 50 cents worth of electricity unleashed in a millisecond or two! Once it's all over simply pick up the mesh mat and remove the 4 AWG connecting leads tossing it down in the basement with the barrels and the rest of the gear the call the coroner. It will appear to have been an apparent divine intervention where God himself struck down the intruder with a bolt of lightning! That is probably pretty close to what the event would look like even if the nosy neighbors actually witnessed it unfold, especially at night! In any event, this hypothetical (though technically feasible) instructional ranting is only a work of fiction for your entertainment. Nobody in their right mind should never even think about assembling such an evil contraption even if well versed in the black arts such as something on this massive scale and level of mental illness. In the most likely event you incinerate yourself or a loved one while attempting to build this or any variant I shall not be held liable... Though I will truly enjoy the gory video in the event your equally twisted friends upload your demise on World Star Hip Hop!

7 replies

Actually i'm imaging to make something big as large oak barrels and to build it differently and to try to charge it with lighting strike.And maybe use some sand.
If i had money right now i would build it.

I have a 38gal barrel here made the same way.. ended up around 5nF from makeshift poor design.. but it adds output like never seen elsewhere.. checkout my community of builders

its only illegal if you live in city limits, you can get rid of the body pretty easy if you live in the country.

I doubt there's a law specifically covering human bug zappers yet... A few folks will have to assemble some from the above plans and actually get caught killing some white people with them first... lol

I am not sure how high the capacity is and instead of 4 AWG cable use >= 0.2mm copper foil (a 1x1cm piece of it will only loose 1 watt at 1000 amps)

Just connect it to a voltage source (eg: a 12V battery, a kV PSU)

I made it. It didn't work. Charged with 12V of DC at 1.2 amps. Nothing happened after discharging. Where did that giant blue arc come from?

1 reply

That giant blue arc is at least 4kV. Leyden jar capacitors are not designed to operate at low voltages, you are better off finding a 1F audio capacitor.

If you add lemon juice to the water will it make it more conductive ?

1 reply

Lemon acid will do that since it has 3 or 4 (i forgot it) conductive things per molecule.

you know what im thinking? worlds strongest electromagnet ever! thanks for the compaciter i will try to make it!!

5 replies

 The strongest ever is over 500,000x stronger than the earth's.

The strongest ever has been recently created using graphene inside a lab environment measured at about 300 telsas. To put this into relativity, a really strong magnet, one of those rare earth, or neodymium magnets are about .7 teslas. Read up on it here: so 10 Million at this point!