The key to the strength, as I analyze things, is that you have four thicknesses going through the closing loop, as with the button knot. However, I had a hard time getting the bury to extend past the knot, which was huge, even after I tried hardening the knot. I made one bury about 8 inches and it is there. The overhand knot is much simpler, that is true. If I have the time and patience, I prefer the button knot which is smaller and takes far less line.
Yep, the four thicknesses is the key to the +200% breaking strain. A big knot helps which creates the issue you called out, after a few you figure out how to get the lengths right. Thanks for stopping by and taking the time to engage.
Looks like a great way to make a soft shackle. I followed along with the video using 1/4" (6.35 mm) line, 39" (1 m) long and when I got to the part where the overhand knot is tied, I found that my line was too short to tie the knot. I'll try it again using 48" (1.2 m) and see how big of a shackle that yields.
It is a great way to make them playing with the length you will quickly find a formula that works for you. Thanks for stopping by and sharing how you got on.
additional note: At the last minute, I decided to use 60" (2.36 m) of line instead of 48". That turned out to be too short again. I ended up with a knot the size of a golf ball and a shackle about the same size. It takes all of the loop to open it up to slip over the knot, leaving no room for passing the shackle through or around anything. Probably at least 84" (3.3 m) would result in a useable shackle. Of course, a soft shackle using 1/4" dyneema is way overkill for any of my applications.
