Lesson Notes By Weeks and Term - Junior Secondary 3

TERM – 2^ND TERM

WEEK SEVEN

Class: Junior Secondary School 3

Age: 14 years

Duration: 40 minutes of 5 periods each

Date:

Subject: BASIC TECHNOLOGY

Topic: METALWORK PROJECTS I – METAL JOINING

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Define metal work joints
2. Identify the methods for metal joining
3. Identify the tools and materials needed for metal joining.

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers,

demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures, tools and materials for metal joining.

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

METALWORK PROJECTS I –METAL JOINING

Metal joining refers to the process of combining two or more metal pieces to create a unified structure or component. This can be achieved through various techniques, each suitable for specific applications and types of metals. Common methods of metal joining include:

1. Welding: This involves melting and fusing metals together using heat. Welding is a versatile method that includes techniques like arc welding, MIG (Metal Inert Gas) welding, and TIG (Tungsten Inert Gas) welding.
2. Soldering: Soldering uses a lower temperature than welding and involves melting a filler metal (solder) to join metals together. It's often used for electronic components and smaller metal parts.
3. Brazing: Similar to soldering, brazing uses a filler metal with a higher melting point to join metals. It's suitable for joining metals with higher strength requirements.
4. Riveting: Rivets are mechanical fasteners used to join metals by passing through pre-drilled holes and then being secured on the other side. This method is common in structures like bridges and ships.
5. Adhesive Bonding: Specialized adhesives can be used to bond metals together. This method is often chosen for its simplicity, especially when joining dissimilar metals or materials.

Tools and Materials used for Joining Metals

Tools used for Joining Metals:

1. Welding Machine: Depending on the welding process, this can be an arc welder, MIG welder, TIG welder, etc.
2. Soldering Iron: Used for soldering smaller metal components, especially in electronics.
3. Brazing Torch: For applying heat during brazing processes.
4. Riveting Tools: This includes rivet guns, bucking bars, and other tools used in the riveting process.
5. Welding Helmet: Provides protection for the eyes and face during welding.
6. Welding Gloves: Heat-resistant gloves for hand protection during welding.
7. Clamps: Used to hold metal pieces together during the joining process.
8. Tongs: Used to handle hot metal pieces during welding.

Materials used for Joining Metals:

1. Welding Electrodes or Wire: Consumables used in various welding processes to add material to the joint.
2. Solder: Metal alloy used in soldering to create a joint between metals.
3. Brazing Filler Metal: Higher temperature filler metals used in brazing.
4. Rivets: Mechanical fasteners that are inserted into pre-drilled holes and then secured.
5. Adhesives: Specialized adhesives designed for bonding metals.
6. Flux: Used in welding and soldering to prevent oxidation and improve joint quality.
7. Backing Strips: Used to support the weld joint from the backside during welding.

EVALUATION: 1. Define metal work joining

2. Identify and discuss 5 methods of metal joining
3. Mention 5 tools and 5 materials for metal joining and state their uses.

CLASSWORK: As in evaluation 

CONCLUSION: The teacher commends the students positively