For years I've been soldering with normal Sn60Pb40 solder wire. But now I try to switch to lead free solder. In many forums over the internet I found the Amasan BF32-3 solder wire. It's a Sn95Ag4Cu solder wire with 3.5% flux.
So I tried it and was very disappointed. Nearly every solder joint was looking different. Some of them were (partially) shiny; some (the most) of them were dull. And the worst thing was, that even with additional flux, the solder didn't flow like the leaded. So there is no way, I could solder fine pith SMD stuff with it.
I’m using a JBC soldering iron station with a C245-907 2.2mm chisel tip and tried different temperatures starting with 290°C to 360°C. The best results I get with about 315°C, with 350°C I got the worst results. I used the Amtech NC-559 Flux – the original, not the fake from china.
Some other guys told me, that maybe the solder wire is not the best. That's why I'm looking for other soldering wires. But there are so many on market. Some with copper, some are Sn96.5Ag3.5 like the Amtech ASN96A3.5-0.50.
So can someone tell me, with what type of solder wire or what product I can get nice shiny solder joints. And yes, I now that dull joints were not a sign for a bad or even cold joint.
Best Answer
For things that require RoHS, I've been using a version of lead-free popular with assembly houses- Sn99.3/Cu0.7 2% flux, which seems to work okay.
The joints are not quite as shiny as the beloved Sn63/Pb37 with RMA flux, but quite acceptable.
Left two joints are lead-free, right joint is Sn63/Pb37.