Lesson Notes By Weeks and Term v4 - SHS 2

Lesson Video

This page supports the lesson note with a companion video and a short classroom-ready summary.

For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.

Performance objectives

• Identify the major parts of a lathe and a shaping machine.
• Explain the functions of each part.
• Demonstrate the basic operation of these machines.
• Understand the importance of these machines in local industries.

Lesson summary

This lesson introduces two foundational machines in every engineering workshop: the centre lathe and the shaping machine. These machines are often called "mother machines" because they can be used to create parts for other machines. In Ghana, from the skilled artisan at Suame Magazine in Kumasi to large manufacturing plants in Tema, these machines are essential for creating, modifying, and repairing metal components. Understanding how they work is the first step towards becoming a skilled technician, engineer, or innovator who can solve practical problems in our communities. We will learn to identify their parts, understand their functions, and know the basic operations they perform.

Lesson notes

This lesson focuses on two powerful machines used for shaping metal. We will break down each one. A. The Centre Lathe (The "King" of the Workshop)

The lathe is a machine that shapes a workpiece by rotating it against a stationary cutting tool. Think of a potter shaping clay on a spinning wheel; the principle is similar, but with metal and a sharp tool.

Major Parts and Their Functions:

| Part | Description & Function | | :--- | :--- | | Bed | The foundation of the machine. It is a heavy, rigid frame on which all other parts are mounted. The guideways on the bed ensure the precise movement of the carriage and tailstock. | | Headstock | Located on the left side of the bed. It houses the main spindle, gears, and motor. Its job is to hold and rotate the workpiece at various speeds. | | Chuck | A device mounted on the headstock spindle that grips the workpiece. Common types are the 3-jaw self-centering chuck (for round or hexagonal work) and the 4-jaw independent chuck (for square or irregular shapes). | | Tailstock | Located on the right side of the bed. It can slide along the bed and be locked in position. It supports the other end of a long workpiece or holds tools for drilling, reaming, and tapping. | | Carriage | Moves along the bed between the headstock and tailstock. It carries the cutting tool. It consists of several parts: Saddle (slides on the bed), Cross-slide (moves the tool towards or away from the workpiece), Compound Rest (swivels for cutting angles/tapers), and Tool Post (holds the cutting tool). | | Lead Screw | A long, threaded rod located at the front of the bed. It is used specifically for cutting screw threads on the workpiece. It moves the carriage at a precise, controlled rate. | | Feed Rod | A long, smooth rod, also at the front. It is used to move the carriage automatically for general turning and facing operations (non-threading). |

Evaluation guide

• Demonstrate the use of lathe and shaping machines.
• reasoning
• In mixed ability groups, assist learners to identify the major parts of the lathe
• and the shaping machines and brai nstorm their functions in the school