Following up on their climbing shoe rubber friction test, Spadout has recently released a belay device friction test. While
highly unscientific not rigorous, this is at least a nice starting point for an objective debate over which tube-style belay device is best (they did not test auto-blocking devices). Their overriding view on the tests were:
We believe two key factors that distinguish belay devices are the range of friction the device can provide as well as the maximum friction it can achieve. You want low friction when feeding the rope and high friction when locking-off.
The friction study ranks a large group of popular belay devices on a numerical scale based on several criteria in their tests using different diameter ropes.
A locking carabiner was clipped to a bolt and each belay device was attached to the biner. The rope was passed through the belay device. The slack on the â??climberâ?ť side of the device went around a pulley and was attached to a 50 lbs weight. The weight and the pulley allowed the belay device to feed and settle naturally. The â??handâ?ť side of the belay device was attached to a spring scale to measure the force.
The force on the spring scale was recorded. This test was repeated 10 times (resetting the slack on the â??handâ?ť side between each test). After doing ten feed tests, the spring scale was moved to the lower lock-off test position and ten more tests were performed.
I was pleased to see that my all-time favorite (and current) belay device, the Trango Jaws, was ranked first in the testing. I’ve tried many belay devices and I’ve always come back to the Jaws. Specifically, I feel the deep V shaped grooves on one side provide high friction and nice fall catching for even the most heavy climbers. Flip it over and the side without the grooves gives you much less friction for easy rappels. Any thoughts on this study? What’s your favorite belay device?