Bluewater Canyon Rope 200 feet by 9.2 mm -- weighs 8.2 pounds. 5000 pound test (22.2 kN). 3.8 percent elongation at 300 pounds. Sheath mass 54 percent. Nylon core, polyester sheath. I bought this rope years ago and it has served me well, mostly for rappeling into abandoned mines rather than canyons.
A new version is now available from Bluewater, the Canyon Rope DS. The "DS" stands for dual sheath. The sheath has alternating strands of technora and polyester for improved cut resistance. I do not own this rope.
Sterling Canyon Lux 200 feet by 8mm -- weighs 6.0 pounds. 5440 pound test. 3.9 percent elongation at 300 pounds. This is an exotic (and expensive) rope. The core is polypropylene surrounded by braided spectra. The sheath is a blend of technora and polyester.
Imlay Canyon Gear 6mm pull cord This is 100 percent polyester for less stretch than nylon. 2200 pound test. 4.1 pounds Consider the following quote from Tom at Imlay Canyon Gear:
I find myself using pull cord less and less, these days. Only in very specific instances, where it has big benefits. It is a good technique to know, to understand and to use occasionally, but put me in the crowd that thinks pull cords are over-used. I prefer inviting a youth along who is strong enough to carry all the rope. And carrying real rope. So much more useful.
Spectra is a trade name for extreme molecular weight polyethylene. Dyneema is the same stuff, but with a different trade name. The claim is often made that at equal weights, Dyneema is 15 times stronger than steel. 3/8 inch Dyneema rope fails at about 17,000 pounds, while 3/8 steel cable fails at 14,500 pounds.
Adventures in Computing / tom@mmto.org