The Great Lightbulb Challenge!

[YT2095]

ok so we`ve had the Battery/LED challenge, now for something to REALLY get you all thinking!

 

the challenge is to make your own Lightbulb, it must be a Filament type bulb and use no more than 12 volts!

the current (amperage) is entirely up to you

it must involve no electronics other than the power supply unit of 12v, and can be whatever weight you want it to be (theres no restriction of weight in this challenge).

HOWEVER!!!! (here`s the hard part), it must be bright enough for you to read a book in a totaly dark room!

 

the winner is the one who`s bulb lasts the longest! so stopwatches at the ready, and Good Luck to you ALL! )

 

 

send pictures in here where possible

[Crash]

Sounds fun, So you mean the time untill the light bulb burns out?

So everything else is up to us e.g. the argon gas inside the bulb? what type of glass, Pyrax?

.........Left to go make light bulb

[YT2095]

yup, from the time you power up your bulb, until burnout, that is the challenge, with the caveat that you MUST be able to read a book in a 100% dark room using only this as your light, and must not be more than 12 volts. fillement type bulbs only

 

you can use whatever gas you like, whatever glass/ plastic etc... it`s all up to you, the only rules are the ones stated

[Crash]

I cant find a decent filament, HELP

[aman]

No braille. I'm gonna try bustin up this junk TV and and using the gun and phosphorescense. If I put a string in it with a coating of the crap on the inside of the tube, is that a filament? I wonder how much light I'll get. Kobayashe-maru cheating

Just aman

[YT2095]

that`s all part of the challenge

I`m having a hard time getting anything to last more than a few seconds also, a pen spring seemed to be the best so far in a jar of carbon dioxide, I can`t afford argon and my friends MIG welder is out of gas too

I never said it was gunna be easy )

[xXxAuroraxXx]

A few questions...what is the purpose of the gas inside of the bulb? Exactly what does it do? And why are certain gases used and certain gases not used? I can get nitrois oxide relatively easily

 

 

Uhh, don't know if I spelt nitroisoxide correctly

[Lance]

The inert gas is to keep the filament from burning. Other than that im not sure why different gases are used.

[xXxAuroraxXx]

Alright, well I'll see what my imigination can come up with

[YT2095]

another way as opposed to filling it with an oxygen free gas, would be to use normal air and work out a way to consume the Oxygen in it with the bulb sealed.

it`s not as hard as it sounds with a little imagination

 

be carefull when making an evacuated container though, especialy if your using glass, they can implode! so maybe if you cover your container in clear sticky backed acetate sheet or really thick sellotape, it`ll stop any bits flying around if you did accidently break it

[Crash]

Would ya be able to obtain the gases from an old light bulb, say they would be heavier than air (if argon) so you could trap most of it some way, im not giving up that easy

[YT2095]

well you COULD, but it would be heavily contaminated with normal air.

since the bulb is under low pressure, as soon as opened it, air would rush in and then you`de have normal air with a slight increase in Argon content, it wouldn`t work really.

Nice try though! and good thinking

[Crash]

So really the most ideal gas would be in oreder of teh least reactive? Would CO2 work then? its pretty unreactive, although with the electricty there, yiou'd need it as close to pure covalent as you could possibley get?

[YT2095]

anything that won`t react with the metal at high temperatures.

that leaves inert gasses, very good vacuums, or non inert gasses that won`t react.

actualy, if you`re going to make CO2, why not go the extra distance and make CO, it`s much less reactive and just as easy to make

the way I figure it, is that I know of many metal carbonates, and carbides are quite difficult to make, so CO seems the better way to go maybe?

[Crash]

kk, CO is my new mission

[YT2095]

Hmmm.. here`s a weird thought that just occured as I was pondering on gasses for use.

these "halogen" bulbs. halogens are powerfull oxidisers, how come they`re used and don`t effect the metal filiments?

[Lance]

The filament is operated near the melting point (tungsten) and is constantly evaporating. As the tungsten vapor nears the cool surface of the bulb it combines with the halogen to from tungsten halide rather that become deposited on the bulb. It then flows back the the filament and the intense heat decomposes it. The freed tungsten is then redeposited on the filament.

 

The filament is constantly recycling rather than condensing and becoming a smudge on the the bulb.

 

So they DO effect the the filiment.

[YT2095]

sweet answer!

 

so maybe we can use Halogen gasses instead!

(obviously at low pressure).