Good points Wiggy, heatshrink is even better.
Jaycar have decent heatshrink that is slightly thicker than normal and contains glue.
For those that are new to all this, you buy a length for a few $$, looks like a drinking straw,cut a section 2-3cm, separate your the 2 wires you cant to join or resolder, slide the tube over and out of the way for now, resolder the join as normal, the when its cool, slide the heatshrink over the join. Heating it with the side of the soldering iron or a lighter will make the tube contract down and activate the glue, sealing the join and jobs done.
Sorry if this is all known to everyone, but if not hopefully someone might pick up something new.