This is the seventh post in a series that will eventually comprise an activity-based, unit pioneering program curriculum.
VII. The rope tackle is a major player when there’s a need to add guy lines to stabilize a pioneering structure, or to increase the torque on a monkey bridge’s hand and foot ropes. Whenever there’s a need for tightening and securing a load-bearing line, this combination of knot-tying prowess and basic engineering principles is both practical and effective. Applying a rope tackle will be called for on numerous occasions and has been found to have a wide range of uses.
- Scouts will tie a butterfly knot to create a fixed loop in the standing part of a line.
- Scouts will form a working rope tackle and use it to lift a weight.
- Scouts will secure the load they lift, using the hauling end of the line to tie two Half Hitches around the length of ropes extending from the butterfly knot, and cinching the hitches up tight against the knot’s fixed loop.
- Length of manila rope 1/2 to 3/4 of an inch in diameter with one end threaded around a ground-level anchor, for purposes of demonstration
- Horizontal hitching rack(s) secured 5 feet off the ground with one 4-foot nylon cord hanging down for each Scout
- One 2-1/2 pound barbell weight (or facsimile) for each Scout
- The instructor(s) methodically demonstrates how to tie a butterfly knot in the large diameter rope.
- With an attendant holding on to the free end of the large diameter rope, the instructor(s) proceeds to use it to form a rope tackle.
- Each Scout stations himself behind a cord on the horizontal hitching rack. Using the large diameter rope, the instructor(s) slowly goes through each step to tie a butterfly knot, as each Scout attempts to duplicate the steps with their cord.
- After the Scouts have grasped how to tie a butterfly knot, they tie one again, about 2 inches from the horizontal pole of the hitching rack.
With their fixed loop in place, each Scout passes their cord’s running end through the weight, then through the fixed loop forming a rope tackle.
- Pulling on their cord’s running end, which now becomes the hauling line, each Scout uses their rope tackle to raise their weight.
- Each Scout can compare the resistance they feel by (1) pulling the hauling line down and away from the rack, and (2) pulling it up towards the rack.
- With the rope tackle tied in the large diameter rope, the instructor(s) demonstrate how to tie it off by forming a half hitch with the hauling line around the length of ropes extending from the butterfly knot, and cinching it up tight against the knot’s fixed loop. He also adds a second half hitch, working it up against the first.
- With the instructor’s help as needed, holding the position of their lifted weight, each Scout ties off their rope tackle with two half hitches.