Picture of Lead light (Not a LED)
This Instructable is about how to make a lead light that can also be used as an ignition system.

Disclaimer: this is a dangerous project.
1.This is very HOT up to 300 degrees minimum so be careful.
If you get hurt during this project it is not my fault.

Step 1: Materials

Picture of Materials
Battery (at least half an amp other wise it wont work)
Refills for refillable pencil also known as carbon graphite
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Wyle_E6 years ago
You might get the carbon to last longer if you enclosed it in a jar with an inert atmosphere. Helium would probably be best, but nitrogen or even carbon dioxide would probably work. The temperature rise would expand the gas, so you would need a one-way valve to relieve the overpressure. Something as simple as a loose rubber stopper would be enough.
ReCreate Wyle_E6 years ago
Hey ive got carbon dioxide it comes out of my nose(right?)
Or your mouth.

You guys should not try CPR.

Haq3r00 Wyle_E6 years ago
It would be far more fun to put one of these graphite rods and 2 wires into a very small bottle of compressed butane, with a remote switch of course... It would have the same effect, the temperature would expand the gas, but no valves needed, the container itself would release the pressure Somehow though I don't think the graphite would burn for so long.
oni (author)  Wyle_E6 years ago
Thats a good idea ill have to try it one day.
oni (author)  oni6 years ago
I just tried it it except without the valve and all the gases started coming out of the lid.
Haq3r00 oni6 years ago
Haq3r00 Wyle_E6 years ago
Main issue would be when the Graphite cools down again... the jar would break from the vacuum.?....
osgeld Wyle_E6 years ago
even if you put it in a vacuum the light would burn much brighter and for quite a long time, its almost as decent as a modern light bulb

check out this link

junits156 years ago
this is very cool execpt, for the fact that the lead burns away, i wonder how this would look in a complete vacume.

there is no such thing as complete vacume

it exists theoretically

it would look like this.... First Few Seconds ______________________________ | _________Light___________ | |______________________________| After First Few seconds: Blindness: due to the explosion of rapid heat expansion and CO2 produced by burning Graphite, resulting in plastic/glass shrapnel to blind you.
actully it cant burn in a vacume so I'm pretty sure it would not explode.:)
Nexnaught6 years ago
Is there a fancy name for the switch/adapter cable? Also, where can I get the materials?

Materials: anywhere (Radio Shack, Home Depot etc.) i got the batt. from a broken rc, but u can get those from radio shack. it might be a bit expensive though.

hsarode13 years ago
To make it last for more than 1 min. what u have to do is. take a glass jar make two holes for the wire to pass in and then insert the wire and touch the lead ends then open the cap and put a tealight and close the jar after sometym the candle will go out of oxygen, so no oxygen the filament won't burn up soo fast.
imakethings6 years ago
cant it work with a 9v battery? does it needs to be 9.6?
oni (author)  imakethings6 years ago
It dosnt matter as long as it has high amps so no a 9v wont work
bigredlevy oni6 years ago
a couple of rechargeable 9V batteries wired in parallel would probably have a high enough current output though right?
oni (author)  bigredlevy6 years ago
That should work and probably be brighter than mine!
it splodes with 2 much current, so be careful
put like 6 or seven D batteries in parallel
Killa-X6 years ago
I tryed this with 0.5 pecil lead, and 12V 2A. It got SO BRIGHT that it was like a lightbulb. It actually was like looking at a mini sun it was so intense.. It lasts only 5-8 seconds, but it glows my room up good. This is when i touch the connection to it very slightly... doesnt last long but its BRIGHT
just like an ark lamp
This is how they came up with the light bulb (it wasn't just Edison doing experiments like this), encasing the carbon (pencil lead) in a glass jar under vacuum would make it last longer and probably burn brighter... :)
DonQuijote6 years ago
how many amps does this stuff draw?
find the resistance of the graphite(not lead, by the way) and then theres a formula for it.....wikipedia maybe?
ohm's law. i forget how it goes but the one you want is:
voltage X resistance(in ohms)= amps
I was thinking the formula for the power consumption of a resistor. But ohms law is E=IR i knew that. E being voltage, I being amperage, and R being resistance.
power consumption in watts.....
Errrr, well.....

Ohm's law is U = I*R with U = Voltage, I = Current and R = Resistance.
Or, if you divide both sides by R and flip the around: I = U / R

Since the power for DC is P = U*I, you will find that P = U*U/R = U²/R
(double voltage gives four times the power!)

Since graphite has a pretty low resistance the current could be really high. For a valid calculation you would have the source resistance of the power supply (the battery here) into account.

So the resulting current will be:
I = U / (Rgraphite + Rbattery)

The inner resistance of NiCd or NiMH batteries (better accumulators) is very low. Bigger packs can drive ten or more Amps easily. Togehter with the low resistance of the graphite this results in the nice light show. (And is the reason why some of the laptop batteries exploded in the last years). So don't try that with alkaline or zinc-coal batteries - it's just a waste of money. The inner resistance of those is too high and will limit the current and the fun.

Boy, these accumulators would have made some of my first experiments in electronics so much more fun... ;-)
I think the formula for the power consumption(in watts) of a resistor is P=I2R, P being watts.
Yep, you are right. As P = U * I and U = I * R you might substitute U and get P = I² * R (always R in Ohm, I in Ampere and U in Volt).

But, with a 'normal' power source (that is a voltage source) you have a constant voltage (U) and you current will follow according to I = U / R. Normal batteries, accumulators or (especially) regulated power supplies act as constant voltage sources. That is within reasonable limits, things change when the source is shorted or heavily drained (like here). That's when the inner resistance and other effects (chemical etc.) come into play and make the voltage not be a constant factor any more.

If, on the other hand, you have a constant current source (not easy to be found, but can be done easily with an electronic circuit) the resulting voltage on a resistor will follow U = I * R and you will get the power with the formula you gave.

It just depends on the type of your source. Constant voltage vs. constant current. For easy designing, accumulators are treated as constant voltage type (until near empty). In real life... well, life is complicated, isn't it?
ranm verence6 years ago
Remember, the restistance can be OHMIC or non-ohmic, meaning that the resistance changes as the temperature of the graphite increases/decreases.
DonQuijote ranm6 years ago
graphite's resistance gets lower with the increasing temperature, at least up to a point, so i am pretty sure this thing needs a huge amount of current, but i was wondering if anybody ever bothered to MEASURE the ACTUAL EXPERIMENTAL current.
ok, i measured it meself and i got a reading of about 4 amps, but with the multimeter in between it did not got as bright as without, despite the fact that i used the un-limited current pins on the multimeter. you know, the ones that blow up your meter if there's more than 20 amps on it. either way, i figure it has some sort of inner resistance, so without it , it probably draws a bit more....... 4 amps, times the 5 v tension i put on it, that is about 20 watts of power draw......
Its graphite... Can draw any amount of amps you like... Can also draw: Houses, Cars, And Fruit.
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