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View Full Version : So I'm looking for a tiny LED...



Matt Thorn
05-10-2011, 03:13 AM
...to put under the glass eye of a vintage Graflex. A nice, blue LED to light up the glass eye, without taking up too much much space. Preferably flat.

So last night I'm online, S.U.I. (shopping under the influence), and I find what looks to be just the thing.
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Looks sweet, huh? Just the thing!

Now maybe I was feeling...small...at the time, because those dimensions (2 x 1.5mm) seemed perfectly reasonable to me.

This morning they arrived bright and early, and, still half asleep, I opened the package and was confused by what I found. Two small ziplock bags containing what looked like black, ribbed bands of some kind. So I put on my reading glasses and looked more closely. Turns out the bands were the packages--each containing 50 LEDs.

Here's a photo of what I found inside one of the bands:
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No, it's not a Luxeon III. I put that in there so you sabersmiths would have a reference for scale.

Here. Let me zoom in for you:
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Yup. It's the tiny white and yellow thing sitting on the top of the Lux, at the five o'clock position.

It's about 1/5 the size of one of the Lux's soldering pads.

That little fleck takes 3V, 20mA, and puts out 270mcd.

Mind you, this is the larger of the two types I bought. The other is half the size of this one.

The burning question, of course, is how the heck I'm going to solder the thing. I wonder if I can teach one of my sugar gliders how to solder. Baby Kinako should be just the right size for the job:
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Skottsaber
05-10-2011, 03:25 AM
That is an 0805 package SMD LED. The best way to make a breakout for that (i.e get wires soldered to it) would be to get some perfboard (solderable breadboard, google it if you don't know what I mean) and solder is across 2 traces.
That is, of course, assuming you have some knowledge of SMD soldering. If not, youtube is very helpful and hey... you have 50 so no biggie if you ruin one ;)

Good luck :)

Matt Thorn
05-10-2011, 04:03 AM
Ahh. I was wondering what SMD stood for. :oops: I instantly found a very helpful little video on YouTube.

http://www.youtube.com/watch?v=3NN7UGWYmBY
Now I need to buy a loupe and a few other things, and hopefully these hundred little chips won't all go to waste. Thanks, Skott! :D

Crystal Chambers
05-10-2011, 04:21 AM
While I completely encourage the use of new tech, I personally would just drill a hole through the graflex blade holder to allow the blade to shine through. Did you consider this and if so why not? Not bright enough?

Sunrider
05-10-2011, 06:54 AM
I get tweezers, put a rubber band around them, put the led in them. That should hold the LED. Tin very quickly and use 30 gauge stranded wire and solder the wire along the pad sideways. Wiggle the joint with tweezers when done to check.;)

Matt Thorn
05-10-2011, 07:07 AM
While I completely encourage the use of new tech, I personally would just drill a hole through the graflex blade holder to allow the blade to shine through. Did you consider this and if so why not? Not bright enough?
I did try something like that, but it just looked like light leaking through a hole (which it is). Somehow I just didn't like that look of it. There are other reasons, but it's a bit convoluted, and not worth going into until I actually complete the saber.

I get tweezers, put a rubber band around them, put the led in them. That should hold the LED. Tin very quickly and use 30 gauge stranded wire and solder the wire along the pad sideways. Wiggle the joint with tweezers when done to check.;)
Thanks for the tips, Sunrider. I think I might go with perfboard, if only to give the LED a solid base, but it's good to know the alternatives.

Skottsaber
05-10-2011, 08:39 AM
Yeah, I don't recommend soldering directly to any SMD parts under about 1206 size (and even then you risk pulling pads off of the component).
Good luck with your soldering ;)

Jedi-Loreen
05-10-2011, 10:20 AM
I know how small those LEDs are. I used to solder things like that under a microscope. I can't imagine doing it without one.

Skottsaber
05-10-2011, 10:22 AM
The smallest I've done by eye is 0402, but that was getting on the small side of things.
My standard size for board components is 0603, of which I easily do by eye. I love youth :D

Zook
05-10-2011, 11:45 AM
The smallest I've done by eye is 0402, but that was getting on the small side of things.
My standard size for board components is 0603, of which I easily do by eye. I love youth :D

bah I am an old fart (well not that old) and I can do 0402 by eye easily :D

its really more about steady hands and needle point tweezers than sight though IMO. Well I say that because I have perfect vision up close...if I didn't that might cause me to change my mind.

Lord Dottore Matto
05-10-2011, 12:51 PM
0402 all the way for this old fart. :lol: