I have read the couple of threads on here labeled "soldering best practices", but I don't feel they have addressed my main questions.
I recently recapped my Sanyo EZ20 chassis. I am not a complete noob in terms of soldering, but I'm closer to that than an expert.
I have my soldering iron set to 350 (which, I have no idea how accurate that is), and I have a damp rag to clean the tip of my iron. I use 60/40 flux core solder. What I've observed is that my iron heats the joints quickly, and I'm able to remove old solder effectively. I can also make the new connection quickly and securely, but it seems that there is a brown residue remaining on most of my joints. Is this the flux that remains, or is it the green coating on the board that is being burned? I don't feel like my joints have the same shiny silver clean look as the rest of the board. What am I missing?