Picture of How to make your own LED lightbulbs
a tutorial to making commercial-look-a-like LED bulbs.

After many attempts to make all sorts of LED-conversions I finnaly found one solution that is simple and efficient. Of course, you do need a great amount of patience in making this but when you consider the countless hours of pure light -low consumption you'll get, it's all worth it. This tutorial is about converting regular GU4(MR11) halogen bulbs to LED bulbs while maintaining full usability as 12V light bulbs that can be used in indoor task or accent lighting.

Step 1: You'll need the following stuff to start working:

Picture of You'll need the following stuff to start working:
- one halogen bulb (burnt or new since they are really cheap) with no glass cover on front.
- LED's - as many as you want. You may want to keep this number reasonable since more than 22 LED's will make you work painful.
- online acces to http://led.linear1.org/led.wiz , a great LED array calculator you can use to figure out the resistors you'll need depending on your number of LED's and the supply voltage.
- Super Glue & compound glue. You can use other glue as well but super glue sticks fast and I recomend it.
- solder wire, moderate soldering skills, solder gun
- one small piece of 0.2mm aluminium sheet (this is used in printing industry, I work in this field and there are a lot of aluminium plates around here). Any offset printing shop will be kind enough to give you a used one since they use hundreds each month. A cut-out Coca-Cola can will do, once you straighten it.
- a paper perforator (office type, 2-hole punch)
resistors (depending on your needs)
- a few other common household items along with a good amount of patience.
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i LovED!

I LoVeD wille nic, its next project!

celalboz8 months ago

is this 12v considers the fluctuations in voltage say 13.4v comes in will this account for that?

claudiopolis (author)  celalboz8 months ago
No, this one is calculated for a regulated 12v power supply. If you need a higher voltage LED bulb, you'll need to recalculate the resistor's value by changing the voltage in the LED resistance calculator. If not, it'll work, a bit brighter but with a much, much shorter lifespan.
Great instructable.

I have a question - won't this design draw just as much power as an ordinary halogen light-bulb? I understand that LED's use much less power, but surely the rest of the power is going to the resistors within the circuit to maintain the appropriate voltage/current?

Just wondering, thanks.
claudiopolis (author)  FBIRoyLindell2 years ago
Hi there. The short answer is no, this design is much more economical than the halogen bulb. It may not be as bright - but that actually depends on the LEDs used. I'm attaching here an example of a 12 LED array, powered by 12V. As you can see, the resistors together only dissipate 1.2mW. The entire array takes just 721.2mW, that's less that 1W.
Things change when you use high-power LEDs. In that case you need a special LED driver circuit to power those, and that's even more efficient than resistors.
Where can I but LEDS like that? I looked up where to buy resistors and people said radioshack or some other electronics place.

But what about those leds? Thanks
claudiopolis (author)  CharmingCharlie2 years ago
The same place. Radioshack. LEDs are "Light-Emitting Diodes" so any electronic parts vendor should have them. Look for the higher luminosity ones. They're better and you'll get more light.
dagob3 years ago
And what if I want to make it 220v?
olio dagob2 years ago
Get "big" LED with driver for 220 voltage.
seraine3 years ago
There's a small typo here - it would be firm, not ferm. Other than that, nice work.
claudiopolis (author)  seraine3 years ago
Done. Thank you! My English is getting rusty here in Romania.
siamonsez3 years ago
I bought a packet of leds that came with 200 ohm resistors. The calculator says to use 1 82ohm resistor per led which is 3-3.2v @ 20mA with a 4.5v power source. After playing with the calculator a bit a can't find any instance which asks for 200ohm resistors, but using wolfram alpha to calculate 4.5v with 200 ohms of resistance, it says 22.5 mA which is near enough the proper current for the leds.
I don't know if i'm misunderstanding something but it seems to me that these are at odds, any help would be great.
Are the 200 ohm resistors meant to be used with a higher voltage? I'm assuming a 1x array because the pack came with the same amount of leds and resistors, is that wrong? can someone explain what will happen if I wire:
(4.5v) > (3vLED) > (200ohm resistor).
If you have 4.5v power supply to use with led that rated 3-3.2v @ 20mA, to calculate the resistor is: (1.) 4.5 v (power supply) minus 3.2v (voltage drop accross the led) which in your case is= 1.3 volts
(2.) Divide 1.3 volts to .02A ( 20mA) = 65 ohms.
To be safe you can go higher resistance such as 68 ohms or 70 ohms.

I hope I gave some ideas.
bas984 years ago
Why do you need the 1 ohm resistor??
so that the led wo'nt burn
asafche bas983 years ago
See this. it will explain way - http://led.linear1.org/why-do-i-need-a-resistor-with-an-led/
claudiopolis (author)  bas984 years ago
Just to be on the safe side. The LED calculator reccomended it so I used it. It protects the LED from overdriving by reducing the voltage a bit. You might skip it but you'd better be sure of the voltage applied.
ramhardikar4 years ago
Useful i'able.

where did you get halogen bulb with no glass cover on front?
claudiopolis (author)  ramhardikar4 years ago
local chinese low quality store. You can use a glass-covered one too and follow the same guide until you get to the emptying phase when you just us the hammer to remove the inside of the bulb. Then when you have an access hole for a small screwdriver just slide that in until it reaches the glass from the inside. Use the hammer again to pop it out. I made this in my hand using protection gloves and the front glass popped out in one piece pretty easy.
or you can also use a nail, place it on the socket side then break the glass cover. Works for me.
beehard443 years ago
very useful in my current project. I just don't know whether a joule thief can handle 10 LEDs attached to it...
XOIIO4 years ago
You misspelt Fir as Ferm on the hammering part.
claudiopolis (author)  XOIIO4 years ago
sorry about that. But you got the idea, right? :-)
yeah, and I i missed the m, my keyboard was sticky lol
drhall6 years ago
Noticed the diff values for the 5% tolerance & placement for the resistors ... yep I know Bad Boys Only Ravish Young Girls But Violet Gives Willngly ... still mystery.

Bad Boys Ravish Only Young Girls But Violet Gives Willngly.

Black, Brown, Red, Orange, Yellow, Green, Blue Violet, Grey, White.

Brown   Black         Red
1      .         0    x10^    3   =1000 =1k

Lmfao i love it how everyone has a different color code thing to go with it

mine is

Bad Booze Rots Our Young Guts But Vodka Goes Well
Love that one!
Oh and one for remembering Tera, Giga, Mega, Kilo, Milli, Micro,Nano, Pico

The Great Monkey King Makes Microwave Nacho Pizzas
What about "Why Run Backwards You'll Vomit.  (old phone wire colors for a 25 pair cable)  White Red Black Yellow Violet...
what about.... get a card with all of the values on it so you don't have to remember that...
 whats the fun in that. and plus what happens if your dont have the card on you
But, but, what would happen if you were in an air crash, and all your luggage is scattered over the landscape but  you need to boost the power of the emergency radio transmitter by a factor of ten, but daren't use too low a resistor value for fear of burning out your one last hope for rescue.
The card that could save your life is at home, on your workbench.

I suppose you could always get a tattoo...

<small>Seriously though, remembering these things is _very_ handy. Like remembering ohm's law means you don't have to go look things up before you reach for the soldering iron</small>
 its ( bad boys raped our young girls but violet gave willingly)
e.g. 0=black 1=brown 2=red 3=orange 4=yellow 5=green 6=blue 7=purple  8=grey 9=white
Don't forget to append Get Some Now for the tolerance color band.
Gold 5% Silver 10% None 20%
claudiopolis (author)  drhall5 years ago
A little late but better late then never...
Tolerance is not a key factor here. I'm not that perfectionist.
abadfart4 years ago
how bright is it? do you think its bright enough for a projector?
aamwalid4 years ago
Thanx 4 the idea, but please can you tell me how did you manage to cut the aluminum disk in a perfectly round shape that would fit into the reflector ???
hirocaster5 years ago
Anyone knows if this bulb works with regular halogen bulb MR16 powersupply?
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