How to solder with an AA battery and a car battery

You will need a car battery, AA battery, Jumper cables and solder. Touching the carbon rod from AA battery with the solder closes the circuit - this produces heat (& light!) that melts the solder.
What is interesting is that heat is localised and is present only for a very short time (sort of induction cooker).
Be very careful with the car battery and use a battery in perfect condition - I would suggest to use a battery charger (choose one which is fused) instead.
Do the experiment outside the house where air is circulating and wear arc welding goggles and filter mask.
A video of the results is here:
http://www.metacafe.com/watch/733036/graphite_pencil_soldering/

Step 1 Hack the AA battery

This is a very messy step.
You will need pliers and a knife.
Be careful not to break the carbon rod.

Comments

[Electorials]

A car battery can indeed kill you if you put a nail trough your finger, and another nail trough the finger of your other hand, put 12V on both pins, and keep holding that for ten seconds.

Conclusion: 12V is *safe* if you use it correctly.

You can grab a car battery's leads and squeeze them really hard and still not feel a thing. The only way to feel the 12V is when a lead penetrates your skin, and even then you won't die from it.

[fiive]

Don't you think messing with a battery is very dangerous! It can kill you!

[snowluck2345]

pretty sure the battery by itself can't kill you. the amount of ristance from you skin, would prevent almost any amps from going threw you at 12v

[rkr]

It's fine as long as it isn't short-circuited for very long. It would be fairly safe to solder with because the battery's 200 amp potential can't go through such a small diameter conductor as the solder. The only way it would kill you is by exploding from (extremely) careless use and/or starting a fire.

[srilyk]

I actually saw MacGuyver do this with a nail to add the tip bit to the end of a spark plug. Pretty freaking sweet.

[moomoocows]

MacGyver is the god of all who use instructables.

[matroska]

Actually, MacGyver coded Instructables on some scrap paper. He then proceed in using Duct tape to bring it to life.

[aduy]

i heard that he used 500 million transistors from radio shack to make the server for instructables. Hes like the Chuck Norris of instructables.

[jules15]

There's an easier way to use a car battery to solder:  Attach wires to the battery terminals and touch them to what you are soldering.  There will be a big spark and the solder will be melted (It might not be all the way soldered but hey in an emergency..)


(+)  ----------  (solder) ------------  (-)

                     < Spark ! >

[gps93]

I don't think you would need welding goggles, it is virtually like staring at a light bulb, the first light bulbs used carbon filaments, so is it a legality thing or something?

[gmoon]

There is essentially no filament here, this is an "arc lamp."

Regardless of the intensity, arc lamps have very high UV emissions. Some sort of protection should be used--if you value your eyesight.

[Nerdz]

There is only a certain type of Battery you can get Graphite from, Ive found em at the dollar store. The type is Zinc Chloride (These are usually marketed as Super Heavy Duty Batteries) and they will NOT say that they are alkaline types, as those are useless to get graphite from.

D and C cell type batteries have larger electrodes inside of them, so they are probably easier to handle.

[matroska]

 I was just about to comment my very same discovery about this.

My conclusions?
-Only the ones marked "Heavy Duty" as you said (however it wasn't mentioned what exactly it was) have the graphite. The others all have some gooey stuff in the middle.
-My family likes to buy a lot of Duracell. (NOT with graphite).


So yeah, out of a nice mess I only extracted 1 rod. All the others were alkaline (Duracell).

[DieCastoms]

I think every person I know either currently has or has had a Linksys Router. I mention that because the Linksys Router wallwarts are 12 volt, at 2 amp. stone3408 mentions a one amp 15v wart, so I figure the Linksys wart would work well. I probably wont try this because I can easily see how it would work, but will CERTAINLY keep it in mind in for roadside repairs like bleachworthy mentioned. My question is, would someone rate the following batteries from most dangerous to safest for this particular project? I have a VERY VERY large flashlight, 15,000,000 candlepower. It uses a sealed rechargeable 12v 7a/20Ah battery. How about the similar sealed 12v rechargeable starter battery in a Pocket Bike? (I do not know the amperage of this battery.) The battery in a "Jumper Pack" or "Self Contained Jumper Cables" with a supposed rating of 300 cold cranking amps?

[Derin]

That means you don't know me.

[jinventive]

This is actually quite dangerous because of two reasons really: 1) You have a good chance of getting shocked with a high amperage-enough to knock you down or seriously injure someone with a pacemaker if it goes across your heart. 2) You are shorting some pretty big car batteries there which can cause them to explode, or leak which is definitely something you don't want happening. Read the small print on the battery to find out.

[cpotoso]

Absolute nonsense on #1. 12 V is not able to drive a high current through your body (which is the only one that matters). #2 is correct, though. You definitely do not want to short circuit a car battery (I speak from experience, unfortunately)

[agis68]

hmmmmmm consider the Ampers and not only the Voltage...10-12 A are enough to sock and harm you seriously. Think that 12V/10A gives enough power to start an engine. In addition all the materials you use are high risk under the electricity. On the other hand if you don't even have an solder gun then you will carry a dremel? and of course as Cpotoso already said maybe after that your car need other battery so consider also the cost!!! Sorry man, nice as idea but for Breaniak so NOT DO THAT AT HOME!!!

[cpotoso]

Again: 12 V is NOT (NOT NOT NOT) able to drive a significant current through your body. The electrical resistance of your body+skin is in the tens to hundreds of kilo ohms. With only 12V of voltage, a simple application of Ohm's law gives a current of less than 1 mA. Not dangerous at all, save some very few very convoluted cases (e.g. if you put electrodes inside your body, not a good idea if you do not know what you are doing!).

[agis68]

dear Cpotoso. some years I had an accident. I touch the battery poles at the exact moment when the engine started. After 12 years even now i have from times to times some pathetic moves of self stimulated muscles. The power was 12 V but the amps were around 45!!!

[junits15]

well the graphite lead has an extremely high resistance, and will most likley keep the battery in check

[NachoMahma]

. I've been mildly shocked by a car battery when I laid a sweaty forearm on a top-terminal one, but the chances of being knocked down are very low (athough you might hurt yourself getting away from it, it's not enough to cause violent muscle contractions) and the chances of serious injury are pretty close to nil. As VIRON said, it's not impossible, but normal body resistance will prevent electrocution except in VERY rare cases. I wouldn't get sweaty, stand in a puddle of saltwater, and grab the clamps, but I wouldn't hesitate to grab them in the rain on the side of the road - and have. . Pacemakers are not very sensitive to low voltage DC and the pacemaker wouldn't see the full 12V, anyway. AC might cause a problem but not 12VDC. . Unless you short the clamps together, overcurrent shouldn't be a big problem. A carbon rod, especially the size of a pencil lead, will burn up (thus opening the circuit) before doing much damage - built in fuse. You're not welding here - current is maintained only for brief periods when soldering. . None of those things have a zero chance of happening, and I'm glad you posted a warning, but to call it dangerous is an exaggeration.

[rocketman221]

if the 12 volt lines are pushed deep into your skin especially around your heart it could possibly kill you

[jongscx]

well, assuming you had two sweaty hands and accidentally touch the leads you were holding, the circuit would then be formed that would go up the wires- up one arm - through your heart - down the other arm - down the other wire... I'm thinking a battery strong enough to crank a car would be strong enough to cause your heart to go into arryhthmia or possibly even have it stop... and unless you know how to do CPR on yourself or have a pre-filled atropine syringe with a 4" needle...

[VIRON]

It's VERY rare but not impossible to be electrocuted by 12 volts. I once heard of someone touching 9 volt terminals with bleeding hands and getting electrocuted through their heart, but remember that many of us often test those batteries with our tongue! The alligator clips have insulated handles.

[surf237]

but a battery has tonnes of Amps

[VIRON]

Tons of amps is an Interesting way of saying it. But... 12 volts is too weak to push "tons of amps" through the resistance of someone's body ... which is usually around 100,000 ohms.

[shotymaster491]

Only the skin has 100,000 ohms of resistance and that is when it is dry. If it is wet and can get as low as 1,000. Even a 9v battery can kill someone. If you were to take leads that are off of a 9v battery and puncture both you arms or hands with them it could kill you. First you would either have to have been drenching wet or stupid enough to puncture yourself with wires containing current. So as my final verdict i dont think that getting killed by a car battery is possible unless for a lack or better words your stupid but if you are "Baka wa shinanakya naoranai"(Not responsible for anything you do if you think you are part of that proverb)Alway use caustion. Nice structable,...but i do agree with DBLinuxLover a couple posts below.

[Tracy]

A lead-acid battery has low internal resistance, hence is capable of heavy current; but as Viron pointed out, it takes voltage to overcome resistance to produce those amps.

[DBLinuxLover]

ooorr you could buy a soldering iron. Safer, and more precise. Also faster (you dont have to keep re-adjusting the solder.

[surf237]

!!Car Batteries Can supply more Amps then an Arc Welder!!

Let me relate something that happened to a friend of mine, a dentist by trade who likes to work on his sports car occasionally. In preparation for some other work, he elected to remove the battery from the car, using a box wrench to loosen the battery clamps. The wrench made contact with his wedding ring (he's lefthanded), and the ring in turn made contact with the battery holddown. A massive short circuit welded his ring to the holddown and to the wrench, which in turn was welded to the positive terminal.

Car batteries store an enormous amount of energy, and they're optimized to deliver it in a very short period of time. A shorted car battery can easily deliver several hundred amps — more than an arc-welding machine. Within a second, my friend's wedding ring was almost red-hot, and only a fast reaction with his other hand to break the connection by hitting the wrench prevented it from remaining connected long enough to melt. The ring had to be sawed off his finger at the emergency room, and it was more than a month before the burn specialist was sure he wouldn't lose the finger altogether.

Two lessons here. First, remove all jewelry when working with tools, even something as simple as a box wrench. That's fairly obvious, eh?

Second, always remove the battery's ground clamp before loosening the positive. If you remove the negative clamp and inadvertently complete a circuit to ground, there will be no current flow because the ground clamp is already grounded. Subsequent shorting of the positive terminal to ground will then produce no current flow because the current has no return path to the negative post. And, of course, always reconnect the ground last.

[smokehill]

I second the motion on removing jewelry when working on cars, not to mention a lot of other places where electricity and Big Heavy Things lurk. Ditto with removing the ground clamp before you do ANYTHING involving auto electricity. Sure, 99.99% of the time, nothing goes wrong. I learned my lesson when removing the instrument panel from a '63 Valiant. It was a small separate part of the dashboard, held on by a couple of Phillips screws ... what could go wrong? All I had to do was replace one little light bulb that had burned out. Hardly worth taking off the ground clamp, right? As I pulled the panel carefully toward me, the big lug that carried all the juice from the battery to the panel must have just brushed against the edge of the metal dashboard .... instantly black smoke poured out, and from under the hood, and the stink was ferocious, with some quick flames here and there. Every wire in the car was instantly destroyed. It took two of us an entire weekend to install a $500 wiring harness throughout the whole car. Miserable, nasty work. Now I am much more careful about removing that lousy ground clamp first ... but, being human, sometimes it just seems like too much trouble. Eventually I'll be sorry.

[Derin]

yesterday a mechanic replaced a brake detector on the car and ground waqs still on

[lennyb]

i had something like that happen to a 73 340 duster i used to own. a chucn of metal fell down on the starter terminals{it was from the exhaust i think] and shorted it out. the car cut out and all the lights brightened up then popped. when i opened the hood the battery was melting and the main ground wire was just a strip of glowing copper.{always carry an axe in your car lol} took me weeks to totaly rewire the car then a month after that i totalled it by hooking an edge of pavement with the cross member{60 to zero in 2 feet} none of that {except the crash that was my fault} would have happened if the fuses and fusible links hadnt been bypassed by the previous owner, wonky electrical was a fact of life for the 60s and 70s mopar product.

[smokehill]

I'm not sure that electrical systems have improved much since then, with all the electronics & chips controlling everything. I had an 80s Cadillac with an oddball electric quirk I couldn't figure out -- don't remember exactly what -- but finally an auto electrician figured out that it was a blown fuse in a completely unrelated circuit, that I didn't regard as essential. I wouldn't have believed it if he hadn't demonstrated it. He said something largely incomprehensible about juice feeding back through other circuits, and that the wiring was now so complex that it happened now and then. Personally, I detest cars after the 70s, when they became impossible for a reasonably intelligent person to figure out for himself. I still have my '78 Ford van -- rust holes everywhere, ugly as sin, 340,000K -- and I'll rebuild the engine when it goes rather than feed into Detroit's nasty scheme to cheat us out of DIY. I've had a fusible linka on that van leave me stranded twice with no juice in the middle of nowhere, at night, so I finally replaced it with an inline fuse, and I keep a couple of spares. So far, the fuse hasn't blown, so I begin to suspect that fuses are inherently more stable than fusible links. At least they won't cost you $400 in towing, repair & motel bills far from home. Still love those old MoPars, tho. I'd give a lot for one of my old '55, '58 or '61 Chrysler 300s -- they were truly King of the Road.

[Esmagamus]

Come on... not all cars after the 70's have lots and lots of wires and circuits in them. My brother drives a 1994 Citroen ZX 1.9 D that has absolutely no electronic controls on the engine. Mechanical pump, electric start, no AC, basic gauges and nothing else to fail. Electrically, nothing failed in it because there is nothing to fail. The same goes to the company's Citroen C15 van: only 4 fuses.

[smokehill]

Don't know much about the Citroens -- I drove one, once, and the experience was just too weird to ever repeat again. Don't know which model, but it was a reasonably new car in about '73 or so, but it had a brake pedal that didn't move. The harder you pressed on it, the faster you stopped, but there was no movement to the pedal, which I found just too odd to deal with. There just aren't enough Citroens in the U.S. for me to even form an opinion of them, though I like anything with less electronics, which are strictly a scam to make sure the car will soon become too expensive to be worth fixing. A similar process happened with surveyor's instruments, which used to be strictly optical-mechanical and, if you were reasonably careful with them, would last for generations. Then they discovered that if they put in LCD readouts and computer chips, you had to haul it back to the dealer occasionally & spend some money, and generally had to own a second transit if you depended on using it daily. Some of these so-called "improvements" you can sometimes avoid, like the fancy new ABS brake systems that (supposedly) improve your stopping on ice -- though they don't mention that eventually you'll need a fancy switch on the front of the master cylinder that costs 850-1100 bucks. Or the ride-leveling suspension on the Lincolns (and others) that probably have some slight advantage when towing, but as those shocks periodically go, it will always cost in the thousands, not hundreds, until you figure out that there's a conversion kit to dump the whole thing and put on "normal" shocks. As fond s I was of my old '82 cadillac, I got tired of spending 200 - 300 bucks a year to keep heat & a/c running with its fancy "dial your temperature" system. Personally, I didn't find it all that difficult on the older cars to just move a lever back and forth if it got too cool or too warm, and the most it could cost to fix it was a 25-dollar heat control valve every 12-15 years. And Cadillac & Lincoln didn't give you a choice -- all they offered was automatic climate control, take it or leave it. Electronics can be quite neat and handy, but there should be a rule that when they malfunction you can somehow easily bypass them and still have a vehicle that operates in the old-fashioned way. Electronic toys are nice, but nothing as important as actually being able to operate a vehicle should be dependent on the vagaries of some two-dollar microchip made in the Third World. At least when my computer malfunctions it won't leave me stranded in 20-below weather in the mountains, or halfway thru Death Valley.

[Esmagamus]

It seems you had your share of bad luck, or bad engineering. About citroen's in the 70's, they were making some exotic cars, so I'm not surprised about the brake pedal feel. Around that time they decided to put active (self-leveling) suspensions in their cars. The reason was being able to go fast on the post-war roads. While in America roads have very long straight roads, the same is not true for countries like France, especially in post-war country roads, full of holes, zig-zagging around everything you could cram in a little space. Hence, a car with self-leveling suspension in Europe makes a lot more sense than in Europe. By looking at french cars and german cars, you can easily notice who has the best roads by the much higher ground clearance and generally sportier suspension design in french cars. The self-leveling suspensions needed more maintenance but worked fairly well, unlike Lincoln's attempt a making something similar. About mechanical gauges, the one in my car wobbles so much it causes motion sickness. As there is a DIY mechanic manual for the ZX I drive, I probably can replace parts at home, just like I did with the turning lights lever and heater blower in my brother's ZX (yes, there are two). About depending on electronics, the new all-terrain vehicles are the perfect joke. How realiable is a vehicle that would flash the big news in a LCD, saying "general electronic failure" in the middle of Sahara? Where's the electrician to fix it? A few years ago the british government made a special deal with Land Rover so that they could have new Land Rovers with the older engines. The reason why was the fact that Land Rover could not assure the british government that their whole fleet of brand new Land Rovers wouldn't have their electronics fried in case of a electromagnetic pulse, caused by a EMP or nuclear device. Nowadays, few manufacturers make tough, basic vehicles that follow the "function over form" rule. SUVs don't even come with dirt tires these days because they are not expected to go swim in the mud. Hell, in some countries people are too lazy to learn how to drive with manual transmissions, or too commodist to drive a car with no air conditioning. How many reliable vehicles are made today? UMM now only makes UMMs on request because there weren't enough people wanting a tough vehicle with no electronics, no air conditioning, no fancy plastics, 2 mm thick sheet steel all around that would make a Hummer cry, no delicate paint jobs and the looks of a tank. Still, some people proved that it's a proper vehicle, buying two in the scrap-yard and driving them from Portugal to Mozambique. Someday, that brand will be history and only the Russians will make proper vehicles that haven't suffered too much with globalization. Feel free to spend lots of money in fuel. The American government is fat from stealing so much money by not taxing engine displacement and not forcing american car makers to make cars that at least won't burn all of your money in fuel. Some people think 2 dollars per gallon is expensive. Gas in Portugal costs 2 dollars per liter, that's about 8 dollars per gallon, but somehow, we spend about the same. My car does 23 miles per gallon and I say it's a gas-guzzler. Most new European diesels make about 50 miles per gallon. Renaut 1.5, 104 hp vans do more than that. What do you call American cars now? Giving what I know and what you told me, I'd call them parasites chewing the American people and feeding the government and big businesses.

[lennyb]

i think the bad wiring was a north american thing. everytime i bought a chrysler product the first accessory i bought was a fire extiguisher. never had a citroen before {never seen one either} so im sure you quite correct about it.

[smokehill]

I'm suspicious that it's more bad electrical (and electronic) design, as much as the cheap imported parts they use. I drove Chryslers thru the 60s, usually older ones, but when I retired & moved to a farm in '85 I noticed that farmers around here only owned one thing -- Fords, usually pickups or vans. In my business I stuck with 70s Dodge vans, with few problems, but eventually I swapped over to Ford vans (90s), strictly because there was so much interchangeability of parts that I could get a lot of use out of ones I "wore out" before I scrapped them. Ford's interchangeability saved me a fortune in "down time" over the years, so I understand the farmers' preference quite well now. The few electrical problems I ever had with Dodge or Ford seemed to be more dumb design than actual bad wiring, due to their trying to stick too many things on a circuit, or allowing something malfunctioning in one circuit to somehow "feed back" into another circuit and cause it not to work. I'm not smart enough to know what causes than, but I'm certain that some electrical engineer PhD at Ford or Chrysler is paid enough that he should be able to anticipate & avoid a senseless problem like that.