Board Thread:Questions and answers/@comment-43770328-20191117233821/@comment-30049823-20191118225601

Most hair dryers will probably get hot enough to shrink shrink-tubing, but that's a clunky way to do it, especially in a cramped space, and I'd be worried about melting the surrounding plastic with all the extraneous exhaust.

You can generally just sweep the soldering-iron tip underneath it (almost touching it), and since heat rises that will be enough to make it shrink. Simple and precise.

If you have a shrink-tubing "variety pack" (recommended), start with the tightest fit available that will still slide over your splice; it shrinks a LOT, but not an INFINITE amount =D