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General => General Chat => Topic started by: XOIIO on June 27, 2014, 06:29:18 am

Title: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: XOIIO on June 27, 2014, 06:29:18 am
Hey all, I am wondering if there are any nice very low voltage electrolytic capacitors, that are decently sized physically, that would blow if given around 5 volts or so.

I also because I have always wanted to rig up devices, maybe dummy computer mice, or just little gadgets that I could use a micro to trigger the capacitor to blow up, they provide a nice little pop and puff of smoke, however the lowest value caps I usually see are 6.3v, and I am unsure if something rated for 3 volts would actually blow if given 5 volts or not.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: T3sl4co1l on June 27, 2014, 06:41:07 am
Resistance wire (very fine) and a firecracker (if they're available in your area, anyway..).

Electrolytics aren't rated for operation at less than -3V, or much more positive than their rating.  But that's hardly a guarantee for failure; 6.3V caps can operate at -5V (5V supply, installed backwards) for months before failure.

Tantalums are likely to fail at -3V, but I wouldn't really recommend one for a prank, they're a bit lively for that.  Well, so is the firecracker, but that's a limited pop and little or no fire, which a mouse should contain quite well.

Don't suppose you can find a very small smoke / fog generator that's USB powered... actually... I'm sure such a useless novelty already exists...  You wouldn't get the suspicious crackle-pop sound and burnt electronics smell though, at least not without doping the fog juice with phenol and depolymerized bisphenol derivatives.

Tim
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: XOIIO on June 27, 2014, 06:55:21 am
Not much in the way of firecrackers here, and I'm looking for for the smoke than a bang.

I wonder if something like a 10 ohm quarter watt resistor would work well, not really sure what resistance would be good for this sort of thing.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: kizzap on June 27, 2014, 07:29:06 am
I preface this with a "I have never seen a Tant blow"

however I hear that reversing the polarity on a Tant makes them extremely unhappy.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: G7PSK on June 27, 2014, 07:29:43 am
A few milli amp fuse and red match heads make for a good bang, put a bit of talc in with and you get what loos like smoke. I have used this for pyrotechnics in the past.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: dexters_lab on June 27, 2014, 07:42:26 am
just reverse polarity it and it should pop, though i wonder if you might need a few more volts

They go with a fair crack so if your  putting inside a mouse you would probably only need like a low voltage 10 or 47uf.

i was popping a few the other week, i have some nice tantalums ready to be popped, if the weather is good this weekend i might make another video.

Reverse polarity, 30v usually pulling about 3 amps before they pop
Blowing Up A Few Electrolytics @ 240fps (https://www.youtube.com/watch?v=8lyyqtUXgBA#ws)

Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: Psi on June 27, 2014, 08:43:35 am
50/50 Potassium nitrate and sugar makes a nice amount of smoke.
Could ignite it with a model rocket motor igniter.

Just be sure you dont burn someones house down
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: XOIIO on June 27, 2014, 08:48:27 am
50/50 Potassium nitrate and sugar makes a nice amount of smoke.
Could ignite it with a model rocket motor igniter.

Just be sure you dont burn someones house down

What's a bit of arson between friends?

Yeah, I used to cook up KN03 using cold packs and kosher salt, works pretty nicely, just a bit expensive for those cold packs but eh, I should still have a decent sized jar of it somewhere.

Won't have the right smell to it unfortunately.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: Fred27 on June 27, 2014, 08:58:54 am
You've just reminded me of when I did electronics at school. Our teacher promised that if we managed a whole lesson without blowing up an electrolytic capacitor then he'd get the biggest one he could find and blow it up for us (with safety goggles on of course). We managed it. It wasn't all that impressive anyway.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: XOIIO on June 27, 2014, 09:03:58 am
You've just reminded me of when I did electronics at school. Our teacher promised that if we managed a whole lesson without blowing up an electrolytic capacitor then he'd get the biggest one he could find and blow it up for us (with safety goggles on of course). We managed it. It wasn't all that impressive anyway.

Probably wasn't big enough lol.

I made a variable power supply in grade 8, not for school though, but a college class I audited, sadly I drove it too hard blowing up capacitors and burnt it out. Never got around to fixing it, I think I scrapped it for parts a long time ago, but man, some nice big ones can really fill a room with smoke  :D
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: dexters_lab on June 27, 2014, 09:04:44 am
yea i think with the larger ones the rubber seal can pop out easier or they blow the the vent.... or maybe you just need more wattage to pop em properly
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: XOIIO on June 27, 2014, 09:08:01 am
yea i think with the larger ones the rubber seal can pop out easier or they blow the the vent.... or maybe you just need more wattage to pop em properly

Probably, I think less current gives more chance to smoke out (where they just spray a bunch of smoke) rather than just blowing up. I think ramping up the voltage a bit more gradually helps to make them smoke out too.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: AlanR on June 27, 2014, 12:20:01 pm
Tantalum make good fire balls.  >:D >:D >:D >:D
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: Macbeth on June 27, 2014, 07:21:06 pm
When I were a lad, I would get the steel wool from pan scourers and wrap a few strands around some nails tightly, and use that as a detonator with a 9v battery. My gunpowder ingredients were sourced from my local chemists potassium nitrate, sulfur. I powdered down charcoal BBQ bricks too. Often I would have to use different chemists for the saltpeter and sulfur as it was plainly obvious to them when a 14 year old was getting up to when buying such  :-DD

I had to say I was buying saltpeter for curing meat for example. Haha.

Of course in these insane times I would expect to be locked up in Gitmo for daring to play with chemistry and electronics in such a way.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: Someone on June 28, 2014, 12:24:50 am
Not much in the way of firecrackers here, and I'm looking for for the smoke than a bang.

I wonder if something like a 10 ohm quarter watt resistor would work well, not really sure what resistance would be good for this sort of thing.
Resistors tend to just burn cleanly.
Electrolytic capacitors go bang.
Tantalum capacitors smoke.

Conveniently tantalum capacitors are also available in very low voltages, but you'll probably still need a fet to switch the large current and possibly a large electrolytic next to it to provide the initial current.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: tom66 on June 28, 2014, 12:57:03 am
A reversed biased or overvolted lytic only pops violently because of extreme heating and pressure build up. Even the best USB ports are current limited and a mouse will use the thinnest wire practical, I doubt you'd see more than an amp which might make a sizzle but I doubt much more.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: wraper on June 28, 2014, 02:36:32 pm
Hitano EXR is worth a try. At least it took ~10 seconds for 47uF 25V cap to blow up violently on 15V reverse polarity. I've only found 2 leads sticking out of the board and very small paper particles all around. Small cap without a safety vent is recommended  ;D. Unfortunately don't have any of them left to try :-DD
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: rob77 on June 28, 2014, 11:39:51 pm
back in time we got big-ass electrolytics with no vents ;) 4700uF or 10000uF - those were quite a bangs , but hell of a smoke as well :D and the lovely pieces of paper and foil all over the place :D
(i would rather not describe the freaking dangerous firing method of those big caps :D )

that was back in time when i was young and stupid... but i'm not young anymore :D
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: VK3DRB on June 29, 2014, 02:39:17 am
Electrolytic capacitor smoke is quite toxic. Don't blow them up.

35 years ago I made a burglar alarm which would shock the burglar by exploding some electrolytic capacitors. The resultant fumes were very nauseating... an added bonus. Not really a good idea.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: c4757p on June 29, 2014, 03:33:27 am
shock the burglar

Now there's an idea. ;)
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: SeanB on June 29, 2014, 06:54:29 am
Electric fence energiser does that, legally. I have been tempted to install the wiring all the way down the gate, so as to include the bottom, but that is not allowed.

Would stop the drunk guys from using it as a urinal though.

Eskom has a lot of substations with an inner fence ( 3 layer fence)  between the 2 outer layers supported on glass insulators 30cm over a concrete base with a steel ground strap under it. Fence and gate in it are connected to a separate 33kV single phase transformer  via a line reactor, remote disconnect and a recloser, along with a monitor for voltage and current. It is classed as a live work area, done so that they do not get sabotage of the inner yard.
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: kingofkya on June 30, 2014, 09:57:22 pm
Nichrome
Cloth (used as a wick)
Glycerine (used in most diy fog/smoke machines)

Coat the cloth in Glycerine (you can dulute with watter if you want)
Then just set the Nichrome on cloth. Done:)

Like other have said you can't draw too mutch power from the mouse wireing maybe a big cap for some power storage?


I have also coated nicrome with flux, not as much smoke though:)
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: dexters_lab on July 01, 2014, 12:20:12 pm
Electric fence energiser does that, legally. I have been tempted to install the wiring all the way down the gate, so as to include the bottom, but that is not allowed.

Would stop the drunk guys from using it as a urinal though.

Eskom has a lot of substations with an inner fence ( 3 layer fence)  between the 2 outer layers supported on glass insulators 30cm over a concrete base with a steel ground strap under it. Fence and gate in it are connected to a separate 33kV single phase transformer  via a line reactor, remote disconnect and a recloser, along with a monitor for voltage and current. It is classed as a live work area, done so that they do not get sabotage of the inner yard.

perfect use of the resources available!
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: SeanB on July 01, 2014, 07:10:22 pm
They had a few try to steal the fence, but were unable to identify who it was..............
Title: Re: A good very low voltage electrolytic capacitor for the purpose of blowing up?
Post by: XOIIO on July 02, 2014, 06:30:24 am
They had a few try to steal the fence, but were unable to identify who it was..............

Enough voltage and they will be there the next morning to find during your inspection.