- - AGRICULTURE CORE CURRICULUM - - (CLF2000) Advanced Core Cluster: AGRICULTURE MECHANICS (CLF2600) Unit Title: ROPEWORK ________________________________________________________________________ (CLF2601) Topic: SELECTION AND USE OF ROPE Time Year(s) 1 hour 1/2/3/4 ________________________________________________________________________ Topic Objectives: Upon completion of this lesson, the student will be able to: Learning Outcome #: (M-1) - List five common uses of rope. (M-3) - List the factors to consider when selecting rope. Special Materials and Equipment: Samples of nylon, sisal, polypropylene, polyethylene, manila, cotton, and wire rope. References: Birkby, Robert C. (1990). BOY SCOUT HANDBOOK (10th ed.). Boy Scouts of America, Irving, Texas (Check the telephone book under Boy Scouts of America for the name of the local retail store or supply house that handles scouting supplies.) Phipps, Lloyd J., & Reynolds, Carl L. (1990). MECHANICS IN AGRICULTURE (4th ed.). Danville, IL: Interstate Publishers. Evaluation: Unit Exam TOPIC PRESENTATION: SELECTION AND USES OF ROPE A. Uses of Rope 1. Ropes are used to secure livestock and pets through the use of halters, leadropes, and leashes. 2. Heavy loads, such as hay and straw, are secured with ropes. 3. Rope is used in rural recreation for water skiing and mountain climbing. It is also used to tie camping gear on pack mules, horses, and vehicles. 4. Heavy objects are lifted and moved through the use of block and tackle. 5. Ropes are used to support trees and shrubs, secure tents, and act as support lines, guywires, and clothesline. B. Factors to Consider in Rope Selection 1. Use a. Different uses require different kinds, sizes, and lengths of rope. 2. Construction a. Rope is made from a variety of materials, each of which has different physical characteristics. b. Rope construction varies depending on the material from which it is made. Natural fiber ropes are usually woven while synthetic ropes are often braided. 3. Size a. Rope comes in a range of diameters and lengths. b. Common diameters of rope are 1/4," 5/16," 3/8," 1/2," 5/8," 3/4," 7/8," and 1." 4. Strength a. Rope strength is measured as a breaking load. The breaking load is the amount of weight a rope can hold without being pulled apart. b. Rope strength depends on the diameter and the material of which it is made. 5. Flexibility a. Flexibility determines the ease with which rope can be handled or worked. 6. Durability a. The rope's durability is determined by its ability to resist deterioration when exposed to chemicals, sunlight, water, and abrasion. 7. Cost a. The cost of a rope varies depending upon the material from which it is made, the diameter, and the weight. b. Rope is sold either by the foot or by the weight. Table 1 Safe Working Strength of New Fiber Rope1 ______________________________________________________________________________ Working Strength (Pounds)2 ______________________________________________________________________________ Rope Diameter Natural Fiber Synthetic Fiber (inches) Manila Sisal Nylon Dacron Polyethylene Saran 3/8 200 150 400 390 300 150 1/2 440 350 780 745 600 300 5/8 880 700 1,710 1,355 1,100 620 3/4 1,080 865 2,000 1,870 1,600 800 7/8 1,540 1,230 2,700 2,520 2,120 1,140 1 1,800 1,440 3,600 3,220 2,800 1,600 ______________________________________________________________________________ 1Taken from Rope on the Farm, Farmers' Bulletin No. 2130, United States Department of Agriculture. 2Actual breaking strengths are at least 5 times the figures given. __________________________________________________________ ACTIVITY: 1. Complete a chart or matrix that will list the application, type, and size of various kinds of rope. 2. Through class discussion or written quizzes, identify uses of rope around the home, in agriculture, and in rural recreation. Determine the appropriate size and type of rope for varying uses. __________________________________________________________ 7/23/91 RRE/tf #%&C