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Soldering Notes
Now that the LEDs are securely attached to the heatsink with thermal grease, any heat applied
to the solder pads (the little gold pads) of the LEDs will be quickly conducted away into the heatsink.
When soldering, this will be a problem if your soldering iron does not have a clean, tinned tip (new is
best) or does not have enough power – we recommend at least a 50 watt soldering iron. An iron that
does not produce enough heat will fail to melt the solder properly. This can result in a cold solder joint
which has a very high probability of creating a short/intermittent connection, and has a high probability
of destroying all of your LEDs. You should at most take 1-5 seconds to complete each solder joint.
Leaving the iron touching a solder pad for longer than that is not advised. It also probably means your
soldering iron is not hot enough or the wattage is too low.
Tinning Wire and LEDs
Tinning is the process of pre-coating the wire, or solder pad, in the case of an LED, with solder.
Tinned wire and solder pads are more easily soldered together than non-tinned components. This step
is to save headache and trouble later – attempting to solder un-tinned components can cause huge
problems down the line.
To tin wire, heat the wire (not the solder) with the tip of a clean soldering iron for a few
seconds. After the wire is heated, apply solder to the wire (not the tip of the iron). Since solder flows
towards heat sources, it should melt on to and flow through the strands of the wire, coating them
evenly.
There are two photos below. The left is of un-tinned wire, the right is of the same wire tinned.
Tinning LEDs
LEDs are tinned similarly to wire. Press the tip of the soldering iron to the LED solder pad and
apply solder near the tip of the iron. You do not need too much solder. You can tin all of the solder
pads or only the ones you will use. The top photo below is an un-tinned LED. The photo below it has
the bottom left solder pad tinned. If the pad does not get warm enough, the solder will not adhere well.
Ensure some heat gets into the solder pad, but not too much.