Like everything else in the marine world, dock lines are not cheap. You want to do your best to keep the lines you have clean and in good shape so they’ll last you a while. One of the best things you can do is to secure the end of the rope so the dock line won’t fray or unravel.
Some guys melt the nylon end of the rope which might keep it from fraying but creates a big, round piece of goop at the end of the rope that can get caught up on a cleat. Other guys like to use electrical tape to secure a splice or the end of the rope, but the tape will eventually unravel and leave the dock line sticky and messy.
I prefer this quick-and-easy method to secure the ends of my dock lines so they don’t unravel or fray.
Simply place a piece of heat shrink over the end of the rope and shrink it down with a heat gun or lighter.
This works well on three-strand rope as well. The tip of your dock line should stand up for several seasons if you don’t overcook it. When it comes time to update the rope, just cut a few inches off the end and repeat the process.