Blue LED Flashlight Mod

 by Deadly Computer
Here's a quick 10 minute hack to turn an ordinary white LED flashlight into a much cooler blue LED one.
 
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AerialInk says: Apr 8, 2010. 7:35 AM
I read your instructable some time ago, but never really had a reason to switch out LED's in a flashlight other than just for fun. Recently though, I had the need for a portable and bright UV light source. I found two Guidesman flashlights, each under $10, at a local Menards and went to work. Thanks to the inspiration from your instructable I was able to convert both flashlights, one with 9 LED's and the other with 15, with relative ease. I don't know if I would of thought to do this myself, so I wanted to give you my thanks.
Deadly Computer (author) in reply to AerialInkApr 13, 2010. 2:17 PM
no problem that's why i made it!
I do have a question, how is the UV leds?
Because I was recently looking to get a UV light for some stuff, and I'd much rather make my own if possible.
king kolton9 in reply to Deadly ComputerSep 28, 2010. 5:49 AM
do you know any way to teach a 11 year old how to defuse a LED
Deadly Computer (author) in reply to king kolton9Oct 9, 2010. 6:58 PM
what do you mean by defuse?

like diffuse the light so it's not a point, encasing it in clear hot glue is somewhat usefull for diffusing it.

i'm not sure what you mean by defuse though.
AerialInk in reply to Deadly ComputerApr 13, 2010. 5:01 PM
I was more than happy with the ones I bought from http://www.dealextreme.com/details.dx/sku.2398 . If you need the tech specs of the LED's look to the comments on that same page. If I have my flashlights on for a while, they get pretty warm though, but they are bright and that's exactly what I wanted.
LuciferTengu says: Dec 5, 2009. 11:59 AM
you could buy brighter blue LEDs that are made by the same manufacturer of the flashlight from frys.com, since I've only frys sells them. And of the three stores ive been to (all in one day lol) I've only found red. I think coast uses cree LEDs and brands them as their own.
ZOOBREAK says: Nov 2, 2009. 8:39 AM
why don't you just color the LED lightbulb blue with a sharpie or something
joeofloath in reply to ZOOBREAKNov 13, 2009. 4:26 PM
because you'll just let the blue light out, and the rest (white is a mixture of all colours, after all), and the rest will turn to heat. Blue LED's just turn most of the available electricity into blue light, so are more efficient.
mackintoshlinessless says: Feb 26, 2009. 2:27 AM
what about a red blue and green led in it and three swithes to have about eight diferent colours including white
ironsmiter in reply to mackintoshlinesslessJun 3, 2009. 12:33 AM
could do it, but in that tiny space... it's be beyond the authors soldering skills. :-) Seriously though, it's be easier to use three colored led's, and add color subtraction filters to the lens instead.
mackintoshlinessless in reply to ironsmiterJun 5, 2009. 6:55 PM
yeah thats a thought and is much easier
xdarkxsparkyx says: Mar 9, 2009. 2:20 PM
answer me fast plz can u make the light black
ironsmiter in reply to xdarkxsparkyxJun 3, 2009. 12:30 AM
The speed of light is 299,792,458 meters per second. What is the Speed of dark?
cornflaker in reply to xdarkxsparkyxMar 21, 2009. 12:14 AM
Accidently replied to Frogz instead lol You can make it "black" (as in ultra-violet) but not really black. This is because darkness is just the absence of light.
Frogz in reply to xdarkxsparkyxMar 20, 2009. 6:35 PM
there is "black light" leds
http://www.google.com/products?q=uv+led
k300000 says: Jul 13, 2008. 12:48 PM
why wont red or yellow work??
Deadly Computer (author) in reply to k300000Jul 13, 2008. 8:21 PM
it will work with red or yellow, but the voltages are different. the blue LEDs i used were the same voltage as the white ones. If you used red or yellow you would have to have more LEDs or a resistor of some sorts because they use less volts then the blue ones. i also used blue because, i like the color blue better
Derin in reply to Deadly ComputerMay 22, 2009. 11:24 AM
But I read that all LED's can run correctly up to 3 Volts.
ironsmiter in reply to DerinJun 3, 2009. 12:28 AM
Consult http://en.wikipedia.org/wiki/LED For a primer.
Note though, that it is not exact.
The blue led I ripped out of my broken external harddrive won't even dimly glow till AT LEAST 3.5 volts are applied. 3.7 volt Li-ion battery gives it 'just enough' power to run at 'normal' brightness. SOME leds, have resistors integrated, for 5 volt, or 12 volt applications. I even have one BRIGHT blue led, pulled from a toasted external harddrive, that requires 4.3 volt just to light, and begins getting 'warm' at 5.2 volt.As far as i can tell, that one has no resistor in it.... but it may be really tiny, and hiding in the plastic lens body so infer what you will from that.

The problem with using lower voltage leds, with a higher supply voltage, is you are over driving them. they may light up nice and bright for a time, but then will burn themselves out from the thermal overload.

Noodle god says: Mar 12, 2009. 4:46 AM
Where you buy that flashlight O_o?
peede1 says: Feb 12, 2009. 5:24 PM
a red mode would go along way. if im not mistaken , at night red is better on the eyes. helps with your night vision....my astronomy software on my laptop is lit up in red for night..
Thelonelysandwitch says: Nov 9, 2008. 11:49 AM
i have the exact same light
electronic nut says: Aug 13, 2008. 8:27 AM
wwell atleast we know that your not color blind LOL. (it's blue) ah no offence saw an oppertunity and took it dude! \
Estwald says: Jun 23, 2008. 3:45 AM
Same flashlight, I modded mine with UV LEDs from DealExtream.
Cheap 5mm UV LED DealExtream UV LEDs (20-Pack) $2.93 (shipping included)
UVs cheap enough to experiment with. I've modded a few flashlights now.
I'm working up some Instructables on them.
benthekahn says: Jun 7, 2008. 10:02 PM
cool. Maybe ill make a green one?
Istarian says: Apr 12, 2008. 2:01 PM
An easier way is to leave in the really bright white leds and just insert a blue colored filter in front. Could be done cheaply with blue cellophane.
Deadly Computer (author) in reply to IstarianApr 12, 2008. 3:20 PM
that would have probably worked I agree, but, I had blue LEDs, and 20 mins of free time, and I did not have blue cellophane.
www.led-depot.co.uk says: Feb 3, 2008. 12:43 AM
Very cool looking blue. I like it
Lftndbt says: Feb 1, 2008. 1:38 AM
Nice, your right the simple fact it's blue makes up for it...
brainwise says: Jan 31, 2008. 3:26 PM
This is a pretty good idea ... and handy, too. We always need blue lights when working backstage at the theater.
GorillazMiko says: Jan 30, 2008. 8:40 PM
Really great idea! I might do this to the 99 cent store ones, this is a great Instructable, and it looks an awesome blue at the end! About 2 pictures are blurry, but it's okay, you said sorry. :P Doesn't matter, this Instructable rules. Nice job. +1 rating. (added to favorites)
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