Pulley system progression – is it worth it in practice? A pulley system progression is when you go from a small to a large mechanical advantage (MA). For example, from a 3:1s (s means simple) to 3:1sCD (CD means Change of Direction) to a 5:1s, to a 9:1c (c means compound). Note: You need some prior […]
Category: Pulley Systems
Progress Capture Testing for a jigger
Progress capture testing for a jigger I was about to post an article about the jigger (aka a set of fours) – how to build (and troubleshoot) using a couple of small double pulleys and cord (coming soon). I tried to remember if I had ever tested the progress capture Prusik as this would be […]
Build a 9:1 pulley system with a Jigger
Build a 9:1 pulley system with a Jigger Something I am always looking to do is find new ways to make gear more useful. For rescue one of the great tools in the toolkit is the jigger (aka set-of-fours). This is a pre-constructed pulley system made, in this instance, with two double pulleys. It has […]
Pulley versus carabiner efficiency
Pulley versus carabiner efficiency. It’s always a good idea to be prepared for self-rescue when you are out and about climbing, caving, canyoning, or mountaineering. Make sure the gear you have can do the job and you have tried it out. One question that comes up is: Can I use carabiners (to save weight) instead […]
Rope Grab Test Report
Rope Grab Test Report Grant Prattley, Lindsay Main and Andrew Welsh, New Zealand Land Search and Rescue, February 2001. Many rope grab devices are used by the rescue technician for a variety of functions in a rope rescue system. This study focuses on rope grabs used in a slow pull situation as used in a rescue hauling system to […]
Pulley Systems 101
An introduction to Pulley Systems: Pulley system setup Types of pulley systems – Simple, Compound and Complex Mechanical advantage – for simple systems Pulley progression – 3:1-5:1 Put your first name and email address below and Ill send you a 20-page pdf.