I no longer use an electric iron for anything but really fine soldering like on a chip board.
For soldering wires together, I have a very small, fine tipped butane torch. It heats the wires about 10 times as fast, and does an excellent job soldering.
When I am splicing two wires together, I usually flux em, burn all the flux off with the torch, let the wires cool down, twist them together in such a way that the wires are straight (kinda like crossing your arms, the despite the elbows, your arms are straight together) solder them together by placing the blue part of the flame just below the wire (so the blue part does not touch, but the very light blue part does) then apply solder on the top of the wire. Once the solder joint is done, I wait a few seconds, then slide some shrink tubing with that goo inside of it over the joint, and heat it up. Goo fills in the spaces, and seals it right off from moisture and other corrosion sources, and makes a perfectly smooth joint in the wire.