The Selection of Hand Tools

T IS OFTEN SAID that there is a tool for every job. IUsing the correct tool is important. The correct tool may be safer to use, and safety should always be the first concern when working in agriculture. Also, the correct tool is designed for the job and, therefore, may be the most efficient tool. Selecting tools can be confusing because so many tools look alike. Hand tools come in a variety of sizes, weights, and configurations. Hand tools involve many principles of physical science. Knowing science is helpful when selecting a hand tool for a specific task. If you can visualize the function the tool must perform, you have a good chance of selecting the correct tool for the job. Once a tool has been selected, it must be used safely.

Objective:

þ Describe how to select tools for a job.

Key Terms:

Ñ boring tools holding-and-turning shaping tools cutting tools tools tools driving or striking tools layout tools wrecking tools

Selecting the Right Hand Tools

There are many kinds of tools. Tools are devices or implements that perform mechanical operations. Tools are used to do jobs that cannot be done with the unaided hand. Hand tools are tools that operate only with the power of your hands.

E-unit: The Selection of Hand Tools Page 1 u AgEdLibrary.com Copyright © by CAERT, Inc. — Reproduction by subscription only. 020089 Tools must be selected for the job to be done. Knowing tools and understanding the physical science of the task are factors used to select the right tool. One entry-level skill for agricultural mechanics is knowing how to use the basic tools. This process continues to develop as new skills are learned and manufacturers develop new and better tools. Knowing what a tool was designed to do is one of the most basic skills in selecting a tool to perform a particular task. Tools are sometimes placed into categories to make learning their functions more logical. Hand tools are classified by several different methods. One method is to group tools by the functions they perform. The basic categories of tools are layout, cutting, boring, driving or striking, holding-and-turning, shaping, and wrecking.

LAYOUT TOOLS

Layout tools are used to measure and mark. Examples of measuring tools are folding rules, the steel square, tape measures, calipers, and dividers. Examples of marking tools are pencils, knives, marking gauges, and chalk lines. Knowing which tool will be the most accurate and most efficient often requires some experience in addition to your knowledge of tools. Lay- out tools are generally used to measure and mark materials before other tools are used to cut or shape the materials.

CUTTING TOOLS

Cutting tools cut or remove material after it has been measured and marked. Cutting tools may appear similar but perform different tasks. Several subcategories of cutting tools can be identified based on their function or the material they cut or shape. Saws are a typical sub-

b d

FIGURE 1. Examples of cutting tools: (a) crosscut saw, (b) ripsaw, (c) coping saw, (d) miter box saw, and (e) keyhole saw.

E-unit: The Selection of Hand Tools Page 2 u AgEdLibrary.com Copyright © by CAERT, Inc. — Reproduction by subscription only. 020089 category. Some saws cut wood, and others cut metal. Wood saws can be rather complex. Hand- saws are generally divided into two groups, crosscut saws and ripsaws. Crosscut saws are fur- ther divided by their specific tasks, like straight cuts and curved cuts. As more is learned about each tool classification, the task of selecting the correct tool becomes easier.

BORING TOOLS

Boring tools are used to make holes. These tools include drills, bits, and reamers. As the technology improves, more boring is being shifted away from hand tools to power tools. The more you know about boring tools the easier it becomes to select the tool for the specific function you are trying to perform.

a b

h i c e g d f

FIGURE 2. Examples of boring tools: (a) breast hand drill, (b) ratchet bit brace, (c) hand drill, (d) straight-shank twist drill, (e) straight-shank Forstner bit, (f) bit-stock countersink bit, (g) bit- stock twist drill, (h) expansion bit-stock auger bit, and (i) bit-stock auger bit.

DRIVING OR STRIKING TOOLS

Driving or striking tools are used to hit objects, such as nails, causing the objects to pen- etrate materials, or to hit another tool, such as a splitting wedge. Typically, hammers and mal- lets and the tools they impact are striking tools. Hammers come in different sizes and different configurations to make them most efficient at particular tasks. A blacksmith’s hammer would not be a good choice for driving small finish nails, nor would a claw hammer be a good choice for driving a splitting wedge into firewood. Studying hammers and other striking tools will provide the information you need to select the correct tool for a particular task.

Holding-and-turning tools hold, turn, or both hold and turn items. A pipe wrench is an example of a holding-and-turning tool. Holding tools are generally used in combination with other categories of tools—for example, a clamp holding a board in position while it is cut with a saw. Additionally, holding tools can be used to change the shape of some objects. Many holding tools have broad ranges of application in agricultural mechanics. Turning tools are a large category that includes screwdrivers, wrenches, sockets and their accessories, and many specialized tools. Socket accessories are the handles, extensions, and other tools used with sockets.

Open-End Wrench

Pipe Wrench

Adjustable Wrench Standard (Straight-Slot) Screwdriver

Slip-Joint Pliers Channel-Lock Pliers Socket Wrench

Box-End Wrench

Set-Screw or Phillips Screwdriver Allen Wrench

Combination Open-End Box-End Wrench

Lineman’s Pliers

Needle-Nose Pliers

Locking Pliers (Vise Grips)

FIGURE 3. Examples of holding-and-turning tools.

E-unit: The Selection of Hand Tools Page 4 u AgEdLibrary.com Copyright © by CAERT, Inc. — Reproduction by subscription only. 020089 Selecting the correct size holding-and-turning tool is sometimes difficult and may require instruction from an experienced person. Although efficiency is important, a key factor in this category is choosing a tool that can be used safely to perform a particular task. If a tool fails under a heavy load because the tool was too small for the task, you may be injured or property may be damaged. Always select the correct tool for the job and use it safely.

SHAPING TOOLS

Shaping tools are used to shave off, scrape off, or otherwise alter part of a surface to change an object’s shape or to smooth it. Examples are planes, wood chisels, and wood rasps, each of which serves a different purpose. A plane is used to smooth a surface and to change the size or shape of wood material. A wood chisel is used to cut notches or shave off excess wood. A wood rasp is used to smooth rough work or remove small amounts of wood from a curved or irregular-shaped object.

Wood Rasp

Smoothing Plane

Jack Plane Wood Chisel

Block Plane

FIGURE 4. Examples of shaping tools.

WRECKING TOOLS

Wrecking tools are used to pry pieces apart, pull nails and tacks, and move various pieces into alignment for fastening. They are generally considered pry bars. Selecting the correct tool to perform a particular task is often a personal choice. The challenge is to select the correct size of wrecking tool for the task. The size of wrecking tool will vary with the size and strength of the user. Experience and knowledge of how a tool will perform are important when selecting a wrecking tool. A tool too large can be difficult to get into position, while a tool too small may not provide adequate leverage for safe and efficient use.

2 Many factors enter into the selection of tools for agricultural mechanics. Under- standing the task a tool was designed to perform, knowing how to use the tool, selecting the right size, being conscious of the safety factor, and choosing a tool suitable for the size and skill of the user are all matters to consider. Using tools safely is the responsibility of each individual. The size, strength, and knowledge of the user play roles in selecting hand tools. Choosing the correct tool contributes to efficient and safe work.

Checking Your Knowledge:

´ 1. What is the function of layout tools? 2. What is the function of cutting tools? 3. What is the function of boring tools? 4. What is the function of striking tools? 5. What is the function of holding-and-turning tools? 6. What is the function of shaping tools? 7. What is the function of wrecking tools?

Expanding Your Knowledge:

L For each tool category, create a set of plans that requires hand tools from that category to do a hands-on activity for demonstrating mastery of tool selection and use.

Web Link:

: Do-It-Yourself Home Improvement, Repair, Remodeling, and Hardware Store http://doityourself.com Agricultural Career Profiles http://www.mycaert.com/career-profiles