Electronic – Soldering problem with heavier components

(Solid) tip "tinners" are almost always ammonium phosphate with some tin (or tin-lead) bits mixed in. They are moderately aggressive at cleaning oxides off, so shouldn't be used constantly, but only when needed. The best tip tinner is your solder--tips should always be coated with a small amount of solder.

If some of the oxides are just sticking really well, you could try to mildly abrade them on a brass sponge, copper braid, or similar, but you can't be too hard or you will damage the iron plating (good tips are typically copper core, plated with iron, then chromium everywhere but the working area).

Practice good tip care. I use a Hakko iron and tips at work and mine has lasted about a year (moderately light use, maybe 5-6 projects). Put a good amount of solder on the tip when storing it or leaving it idle for any length of time; don't, for instance, wipe it off, put it in the holder, then leave it on over lunch.

Additional guides:

• Hakko Tip Life Checklist (PDF, attachment to above KB article)
• Adafruit Tip Tips (PDF)

Wire to SIL socket:

• Put the socket on a bench vice to hold it still.
• Heat up the pin with your soldering iron, then apply a bit of solder. Don't heat too much or you'll melt the plastic spacer between the sockets. Repeat for all pins.
• Strip wire ends. If using multithreaded wire, it might be a good idea to pre-solder the wire ends too.
• Now, holding the iron in one hand and the wire in the other, heat up the pin and touch the wire end on the iron. Once the solder melts, move the wire end into the molten solder, then move the soldering iron away. Hold the wire still until the solder solidifies. A stable posture will help.
• Inspect. If it looks like a cold joint (matte grey, brittle), add a bit of fresh solder and redo the joint applying afterheat a bit longer.
• Put a 2-3 cm. piece of <3mm heat shrink tube over the joint, pin and wire. Shrink it tight to make it more durable.

Wire to pad:

• Basically the same thing - apply enough pre-solder on the pad to immerse the wire end.

General advice:

• The thicker the wire / the larger the foil you're soldering, the longer pre-heating is required on that surface.
• If the metal you're trying to solder is in contact with eg. metal pliers or bench vice, the tool will conduct lots of heat away making your work difficult.