My son and I are pretty new to RC and though I soldered in junior high 25 years ago and my son has done some basic circuit board stuff, we're struggling with soldering deans connectors and batteries. We have a 25w and 30w soldering iron and 96/4 "Silver Bearing Solder" --- the problem is that it just beads up and drips off without ever sticking to the connector. It does okay on the wire. Is the iron too low of wattage? I'm guessing it is some sort of thing where it's reached the heat point to make the solder turn to a liquid, but it's not hot enough to get to a state where it can really stick.

If I bought an 80w, would that solve my problems?

Thanks,
Hans