Join Date: Aug 2009
Location: Washington, the state
What are you using to hold the wire? If you're using pliers or something else metal, it will act as a heat sink and carry the heat away. Try putting the wires on a piece of wood and pressing down fairly hard with the flat on the tip of your iron. If the wood chars, don't worry (don't use the family heirloom dining table).
Think of soldering as "wetting." You're getting the base metals, in this case two wire ends, clean and the right heat for the solder to melt and flow wet into the surface of the metal and into the strands of the wire. When a touch of solder melts and runs into the wire, you have the temperature right. When the solder forms balls on the wire, it isn't hot enough. When the insulation melts, you've got it too hot.
About that clean part...the metals must be clean and bright. The flux (including the rosin core) chemically cleans the metal. If there is any oil or dirt, clean it off first. Dry moisture. Sandpaper or wire brush oxidation before soldering. (A tip for soldering water pipes with a drip...stuff a wad of white bread into the pipe to hold back the water for a coupl'a minutes. Do your soldering and put the water back on. It'll dissolve the bread like it was never there. Don't use seeded bread.)
"Older people who are reasonable, good-tempered, and gracious will bear aging well. Those who are mean-spirited and irritable will be unhappy at every period of their lives.
"Let each of use properly whatever strengths he has and strive to use them well. If he does this, he will never find himself lacking."
Marcus Tullius Cicero