Have you ever wanted to reflow surface mount circuits but not wanted to pay for expensive solder paste?
Have you ever had a good de-soldering sesion and found lots of old solder particles all over your desk and wondered what to do with it?
Well, I have an answer to both of these questions in one hit. You can make your own solderpaste!
In this instructable we are recycling old solder, and parts of old PCBs and components.
The only non-recycled part is the solder paste.
This is useful for repairs on the go, if you need to solder wires together, you put some of this paste on the joint and use a lighter to reflow.
A little warning first. The used solder you might use could contain lead, especially if its salvaged from old boards. but since you solder you probably has already accepted the risks of such exposure.
Ok, now the formalities are out of the way, here's what you need:
> Safety glasses
> An old board to desolder
> A solder sucker
> Flux paste (or soldering paste as it is sometimes called)
> A pair of abrasive sponges (or some kind of abrasives that won't leave its own dust or flake off)
> A piece of paper to catch the solder dust
> A piece of plastic or something to mix the paste on
> Something to mix the paste with (I used a blanking plate from the back of a PC and a paperclip)
> A cup of tea (I'm English so this is a must for me)
> A good soundtrack (For this instructable I listened to Billy Talent III)
The quality of the paste varies depending on how fine you can grind the solder, the quality of the paste used and the ratio between the two when mixing. This is something you will need to experiment with.
Step 1: Salvaging the Solder
For salvaging the solder it is best to use a solder sucker.
If you do not have one then all is not lost. To desolder without a sucker you can hold the board above the desk, heat up the solder joint and then hit it against the desk or hard object and the solder with splash off onto your desk.
If you do, then you can proceed with desoldering the solder joints. A tip for this part, when you re-arm the sucker, hold the tip over the piece of paper to catch what comes out.
When you are finished, tip the board on its side over the piece of paper to catch any particles that have fallen out onto the board.
When you feel you have gathered enough solder, we can move on to the next step.