Going to try out SMD LEDs on something soon...

[indianatheshepherd]

I just recieved a roll of 100 of these surface mount LEDs from Ebay for $8. I've never tried soldering something this small before, but I'm going to give it a shot. Each LED is 1.3mm long x 0.8mm wide x 0.65mm deep. The soldering tabs are tiny - 0.125mm x 0.3mm.

Anyone done this before? Any tips?

[Cubey Terra]

wow, that is tiny (or maybe your fingers are enormous—I don't know). I imagine they're meant to be mounted on a circuit board, because those tabs look too fragile to support even tiny gauge wire, though I might be wrong. How do you plan to use them?

[indianatheshepherd]

wow, that is tiny (or maybe your fingers are enormous—I don't know). I imagine they're meant to be mounted on a circuit board, because those tabs look too fragile to support even tiny gauge wire, though I might be wrong. How do you plan to use them?

I light all my 1/2500 kits and sometimes it's difficult to get the 3mm standard LEDs to fit in between parts and I have to try to shave them down with a needle file. I figured I'd give these a try for some of the tighter spots. I nearly always use an extremely thin magnet wire when wiring up my lighting, so it might be difficult, but I think I should be able to tack those tiny tabs on the SMDs with the magnet wire. My biggest concern is heat damaging the LEDs during soldering, but we'll see how well they hold up...

[Moongrim]

That small an LED would be prone to ESD damage.

I'd recommend trying a Cold-Heat soldering iron.
https://science.howstuffworks.com/cold-heat.htm

[zookman]

i got one of those .. didnt seem to work all that great but i think back now and i think i was trying to solder the wrong kind of wire . was a craft wire not ment for electronics i think .plus the tip on mine got damaged somehow, not sure if i can get a replacement for it, tho i havnt looking into it yet .

[indianatheshepherd]

Checked out that link and read a bunch of Amazon reviews... Apparently those soldering irons have pretty fragile tips made of graphite. And I'm thinking that the tip may not be small enough to work on these SMDs... you need to complete a circuit and I'm dealing with contacts that are 0.3mm... I'll try a few with my regular soldering iron before I spend money on one of those Cold irons.

[zookman]

ive seen others take the wires and melt the solder onto those first on fine projects and then put onto fragile part and touch iron just long enough to melt the solder again onto the contact point. wish they had some sort of electricaly conductive glue that could be used for such small stuff .

[Moongrim]

Something like this perhaps?
https://www.sparkfun.com/products/11521

https://www.thinkgeek.com/product/b70c/

[zookman]

i can see those working together for lighting a kit . make lil tabs to glue the led to . use the glue here to hold it in place. then the pen to draw the wires to where ya need them to go and attach power to see if they work . then overcoat with favorite paint to seal the " wires " in place .. might have to get me some of these and give it a test

[Bellerophon]

You could try a variation of the method for soldering on a surface mount PCB. All the pads get a tiny dab of solder paste before the components are put on, then the board goes in a low temperature oven just hot enough to melt the solder. Your problem would be to keep the LED and wires from coming disassembled in the oven. You could solder one bare wire across both leads and cut the wire between the leads after soldering.