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Blowing up stuff with capacitor bank!

Step 3Fun with tin foil

Here is what happens when you short out the cap bank with tin foil.

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29 comments

Jul 3, 2007. 1:57 PMSteveUK says:

When I was a kid, I used to just connect up a 9v battery to a high farad capacitor. Then I would use wires coming from the capacitor to makes sparks on tin foil. You can cut through the foil and it's a bit like a mini welding kit.

Jun 21, 2009. 1:17 AMuberdum05 says:

Thats what I did once, I paralleled two 6800uF audio capacitors,which cost nothing, then charged them to 12VDC. They charged pretty quickly and then I discharged them through a metal screwdriver. Big spark, temporerily magnetized screwdriver.

Apr 7, 2010. 8:06 AMbeehard44 says:

OMG WTF?
well, i remebered they pass high or low voltage but high amperage thru metals to make a magnet

Apr 7, 2010. 9:46 AMuberdum05 says:

I think tchnically, it really weakly welded the screwdriver to the capacitors

Aug 31, 2010. 5:13 AMbeehard44 says:

then the metal heated a bit at the tip i guess...

Sep 1, 2010. 2:54 AMuberdum05 says:

Yeah its with the high currents, it worked a bit like arc welding where they use low voltage and high current to melt metal and bond it together :)

Aug 8, 2009. 1:39 PMBogomir67 says:

We used to charge the caps and then throw them at somebody (from the rear, when he was not looking, anyway), and yell "CATCH". Out of reflex - everybody will, getting a ZAP... ... yeah, yeah, I got zapped myself a number of times that way...

Aug 3, 2010. 9:01 PM

Madrias357 says:

I've done that. Too much fun to load up a cap with, say, 30 volts, then yell, "Think fast!" and toss it to someone. For more fun, bend the leads backwards and wear latex gloves, so that the outer edge of the cap has the leads running down it. The gloves keep you from getting zapped.

Aug 27, 2009. 12:37 AMmuttyfutty says:

Woh, My dad (who worked for RS and in the gulf war ) Told me the exact same thing lol, must be quite common!

Jan 15, 2009. 6:08 PMjoinaqd says:

how many uF are those caps?

Jan 15, 2009. 7:56 PMGoodAtIt (author) says:

80000uF

Feb 16, 2009. 2:22 AMuberdum05 says:

3000F supercap from wima will substitute all those capacitors

Jun 18, 2009. 10:38 AM

macgyver603 says:

Where can you buy the capacitors you just mentioned? It sounds like these would be good for building a railgun.

Jun 20, 2009. 5:27 AMuberdum05 says:

A quick note, the couple hundred F capacitors are only rated for 2.5VDC or so.

Jun 20, 2009. 5:24 AMuberdum05 says:

goto http://www.wima.com and have a look around.

Jun 20, 2009. 10:46 AM

macgyver603 says:

Thanks for the link! :⁾

Jun 20, 2009. 10:52 AM

macgyver603 says:

The smiley face should have the exponent sign for a nose, but the computer interpreted this as a hyperscript shortcut. :)

Jun 21, 2009. 1:11 AMuberdum05 says:

lol, i do party smilies <:-> or <:-)>

Jun 11, 2009. 8:25 PMIdeal_Ideas91 says:

Where Did You Get Those Big Capacitors?!?!? How Much Did 1 Cost!?!?! I Bet 1 Costed $20 At Least

Jan 15, 2009. 6:07 PMjoinaqd says:

why dont you make a door-knob shocker?put tape over the door-knob,then put aluminum foil and tape them on the sides and connect them to like 200volts and shock visitors coming to your home?

Jan 15, 2009. 9:20 PMthermoelectric says:

Unless you use small caps, You electrocute the person enough to have a heart fibrillation.

Jan 8, 2007. 5:43 PMKarim says:

Where do you get those bank things?

Jan 8, 2007. 5:48 PMGoodAtIt (author) says:

a garage sale

Dec 20, 2008. 12:32 PM

ReCreate says:

what person sells deadly capacitors in a garage sale?

Dec 22, 2007. 6:10 AMTheAirSpecialist says:

ahhhhhhhhhhh!!!!

Jun 16, 2007. 8:25 PMgirrrrrrr2 says:

why have them just laying in your basement... you should have used them sooner...

Jul 14, 2008. 7:13 AMDerin says:

lol

Nov 18, 2008. 7:27 PMdark_prince702002 says:

i'm amazed you haven't tried making a rail gun or a coil gun with those.

Apr 5, 2008. 2:49 AM

coolpizzadude says:

How much voltage dose it produce

Jun 17, 2008. 5:36 AMDerin says:

the atx can charge it up to 24V but the caps start blowing up at 40V

Nov 3, 2008. 8:43 PMchriskarr says:

It may be possible to charge these capacitors only to 24 volts with a normal ATX power supply, but he's using a modified one, I believe. The modified ones can put out 40 volts.

Oct 7, 2008. 11:54 PMlouis209 says:

How could I make this

Aug 14, 2007. 11:31 AMthat one guy says:

I'm pretty sure you already know this, but wouldn't a switch let you set it off from a safer distance?

Aug 14, 2007. 8:53 PMmikemmcmeans says:

no then the switch would arc and shock his hand defeating the entire purpose

Dec 8, 2007. 11:04 PMJames (pseudo-geek) says:

have the switch power a relay which powers the circuit

Nov 2, 2007. 8:11 AMSpedy says:

You could use a SCR to switch the currents, it would be a lot safer then just touching two wires together.

Apr 17, 2011. 3:08 PMawesomesquared says:

Or you could just use a really long pole

Nov 16, 2007. 6:49 PMjgg says:

Good to see another setup like mine. I have a dozen cap's (25V), AL bus bars, SCR, and some heavy cable cobbled together to make a useful spot welder. Does a great job on thin gauge stainless sheet, and thermocouple beads (using a pure carbon electrode).

Aug 13, 2007. 4:36 PMtechnopenguin says:

What were you measuring on your meter?

Btw those are large capacitors!!

Aug 13, 2007. 8:44 PMGoodAtIt (author) says:

voltage