I replaced the knot above (which I'll refer to as the "slingstone binder" until someone comes forth with its proper name) with xarax binders in a few places to try it out. one was a laundry drying rack that had warped and loosened and was sagging unevenly (pic1). I tied the poles together at both ends using twine to correct it. I tried some hitches and a constrictor, all of which slipped. the slingstone binder worked fine (pic2). last night I replaced them with xarax binders, which worked perfectly. the slingstone binder, like the constrictor, needs a convex surface, so I had to keep the knot right on one of the poles. the xarax binder could float between the poles and used half of the string. one thing though is that when tightening the xarax binder by pulling on the ends, it felt as though the string would snap, so I compressed the drying rack to create slack and pulled the ends to take up the slack. I didn't feel the need to do that when tightening the slingstone binder.
the other test was attaching my bike pump to the frame using paracord (pic3). it has to be tied to a vertical tube, so it has to hold very tightly or it will fall. it also has to withstand vibration and bumps. so far it's gone 7 miles without slipping, but it doesn't feel nearly as tight as the slingstone binder (pic4).
Inkanyezi, that's a good example of use. exactly the sort of thing I was looking for in the "knots around the house" thread. I was only tightening by hand (for both knots), so that may have been why I wasn't getting it very tight.
