I have some old, weathered rope that is as rough as sandpaper. I want to keep using it, but I'm looking for an extra-easy-to-untie loop on the bight for this rough old rope. Any ideas?
Sure. A Span Loop is probably what you're looking for. It's not as good as Butterfly Loop in most aspects, but it usually unties extremely easily.
The first half of tying this is making a Half Sheepshank, also known as a Bell Ringer's Knot. Make this first part using the one handed twist method described for making a bowline. Notice that the bight or loop poking up through the half-hitch exactly matches the end of rope poking up through the signature half hitch part of a bowline as you execute the one hand twist method.
Then just push the bottom loop back, up, and through the top loop. The Span Loop works best when the load is applied downward on the loop when tied as shown above.
Related Pages: Butterfly Loop, Farmer's Loop, Artillery Loop, Pile Hitch