Planishing, Meaning, Purpose and Applications for SS 3

Class: SS 3
Term: First Term
Week: 9
Age: 16 years
Duration: 45 minutes
Subject: Metal Work
Curriculum Theme: Metal Forming and Fabrication
Previous Lesson: Spot Facing, Meaning, Tools and Applications
Topic: Planishing
Subject Matter: 1 meaning of planishing; 2 purpose to level, stiffen, harden etc; 3 planishing hammer and stakes; 4 performs so many operations

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Define planishing.
• State the purpose of planishing in metalwork.
• Identify different planishing hammers and stakes.
• Explain the various operations performed by planishing.

Affective Domain

• Appreciate the importance of planishing in achieving a smooth and hardened metal surface.
• Value precision and care when performing metalwork operations.

Psychomotor Domain

• Demonstrate the correct handling of a planishing hammer and stake.
• Perform a basic planishing operation on a metal bowl to achieve a desired surface finish.

Reference Materials

The following resources were used in planning this lesson:

• 2025 Revised 9 Years Basic Education Curriculum
• Relevant State Unified Scheme of Work
• Metal Work for Senior Secondary Schools Textbook
• The HeadTeacher Scheme of work

Instructional Materials

The teacher will teach this lesson with the aid of:

• Various types of planishing hammers (e.g., dome-faced, flat-faced)
• Assorted planishing stakes (e.g., mushroom, dome, flat)
• A pre-formed metal bowl or sheet metal sample for demonstration
• Safety goggles and gloves

Rationale for the Lesson

This lesson introduces students to planishing, a fundamental metal forming technique used to refine and strengthen metal surfaces. Understanding planishing is essential for students to achieve professional finishes and enhance the structural integrity of their metalwork projects. It provides practical skills applicable in various metal fabrication and artistic metal crafts.

Prerequisite/Previous Knowledge

Students should have basic knowledge of metal forming processes, different types of hand tools used in metalwork, and general workshop safety rules.

Lesson Content/Board Summary

Planishing

Meaning of Planishing

Planishing is a metalworking process used to smooth, harden, and stiffen sheet metal by hammering it against a hard, shaped surface called a stake. It involves using a planishing hammer to strike the metal repeatedly, causing the surface to become denser and more uniform.

Purpose of Planishing

The main purposes of planishing include:

1. To level and smooth out irregularities or dents in the metal surface.
2. To stiffen and increase the rigidity of the metal.
3. To harden the metal through work hardening, improving its strength and durability.
4. To refine the shape and achieve a desired contour in fabricated metal objects.
5. To create a decorative, hammered finish on metal surfaces.

Planishing Hammer and Stakes

Planishing Hammer: This is a specialised hammer with smooth, highly polished, and often slightly domed or flat faces. The polished faces prevent marring the metal surface during hammering. They are typically made from hardened steel.

Planishing Stakes: These are hardened and polished steel forms or anvils with various shapes (e.g., mushroom, dome, flat, teardrop, creasing) that are used to support the metal from underneath while it is being planished. The choice of stake depends on the shape and contour of the metal piece being worked on.

Operations Performed by Planishing

Planishing is used to perform several operations in metalwork, including:

1. Removing hammer marks and surface imperfections from previously formed metal.
2. Achieving a uniform thickness and smooth surface finish on sheet metal.
3. Strengthening seams and joints in fabricated metal structures.
4. Creating specific curvatures and forms in metal bowls, trays, and artistic pieces.
5. Improving the aesthetic appearance of metal components by imparting a refined, hand-worked texture.

Teaching Methods/Instructional Techniques

Explanation, Demonstration, Discussion, Practical Activity, Question and Answer

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Engaging/Questioning

Teacher’s Activity: The teacher greets the students and asks them about previous metal forming techniques they have learned, such as bending or shaping. The teacher then introduces planishing as another important metal forming process.

Pupils’ Activity: Students respond to questions and listen attentively to the introduction.

Learning Point: Introduction to planishing

Step 2: Meaning of Planishing

Time: 7 minutes

Teaching Skill: Explanation

Teacher’s Activity: The teacher explains the meaning of planishing, defining it as a process of smoothing, hardening, and stiffening metal by hammering it against a stake. The teacher uses simple language and provides a clear definition.

Pupils’ Activity: Students listen and ask clarifying questions about the definition.

Learning Point: Definition of planishing

Step 3: Purpose of Planishing

Time: 7 minutes

Teaching Skill: Explanation/Discussion

Teacher’s Activity: The teacher discusses the various purposes of planishing, such as leveling, stiffening, hardening, and refining the shape of metal. The teacher encourages students to share ideas on why these purposes are important.

Pupils’ Activity: Students participate in the discussion and note down the key purposes.

Learning Point: Purposes of planishing

Step 4: Planishing Hammer and Stakes

Time: 8 minutes

Teaching Skill: Demonstration/Identification

Teacher’s Activity: The teacher displays different types of planishing hammers and stakes. The teacher explains the features of each tool and demonstrates how they are held and used in conjunction with each other.

Pupils’ Activity: Students observe the tools, identify their features, and ask questions about their uses.

Learning Point: Planishing tools identification

Step 5: Operations Performed by Planishing

Time: 5 minutes

Teaching Skill: Explanation

Teacher’s Activity: The teacher explains the various operations or applications where planishing is used, such as removing hammer marks, achieving uniform thickness, strengthening joints, and creating desired forms.

Pupils’ Activity: Students listen and understand the practical applications of planishing.

Learning Point: Planishing operations

Step 6: Practical Demonstration

Time: 4 minutes

Teaching Skill: Demonstration/Practical

Teacher’s Activity: The teacher demonstrates how to planish a pre-formed metal bowl using a planishing hammer and an appropriate stake. The teacher emphasizes safety and proper technique.

Pupils’ Activity: Students observe the demonstration carefully, paying attention to the technique and safety measures.

Learning Point: Planishing technique observation

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What is planishing?
2. State two purposes of planishing.
3. Name two tools used for planishing.
4. Mention one operation performed by planishing.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Understanding of planishing

Step 8: Note-Taking

Time: 4 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes into their notebooks, focusing on the meaning, purpose, tools, and operations of planishing.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Recording lesson notes

Step 9: Conclusion

Time: 5 minutes

Teaching Skill: Consolidation

Teacher’s Activity: The teacher summarises the key points of the lesson, reiterating the importance of planishing in metalwork and encouraging students to practice the technique safely.

Pupils’ Activity: Students listen and ask any final questions.

Learning Point: Planishing concept consolidation

Continuous Assessment/Further Study

Type: Homework/Practice Exercise

Instruction: Answer the following questions and prepare for a practical session on planishing.

1. Describe in your own words what planishing means.
2. List three reasons why planishing is important in metal fabrication.
3. Draw and label two types of planishing stakes.
4. Research and write a short paragraph on the safety precautions to observe while planishing metal.

Lesson Keywords

• Planishing – A metalworking process to smooth, harden, and stiffen metal by hammering.
• Planishing Hammer – A specialized hammer with smooth, polished faces used for planishing.
• Planishing Stake – A hard, shaped steel anvil used to support metal during planishing.
• Work Hardening – The process of strengthening a metal by plastic deformation.
• Metal Forming – Techniques used to shape metal without removing material.

Differentiation

Support for weaker learners: Provide simpler definitions and focus on identifying the main tools and purposes. Allow them to observe the demonstration closely and guide them through a simple planishing motion without actual metal if needed. Provide labelled diagrams of tools.

Extension for faster learners: Encourage them to research different types of planishing finishes (e.g., planished, highly polished) and their applications. They can also be tasked with attempting a small, simple planishing exercise under close supervision.

Suggested Lesson Videos

For further understanding, students can search on YouTube for:
planishing metalwork SS3

Teacher Guide for Using This Lesson Plan

Before the lesson, ensure all planishing hammers, various stakes, and a pre-formed metal bowl or sheet metal sample are readily available and in good condition. Begin by engaging students with their prior knowledge of metal forming. Clearly explain the meaning and purpose of planishing, using visual aids if possible. During the demonstration of the planishing hammer and stakes, allow students to handle the tools (under strict supervision) to familiarise themselves with them. The practical demonstration of planishing a bowl should be clear and focused on technique and safety. Emphasise the importance of safety goggles and gloves. Students should copy the Board Summary notes after the main concepts have been taught and understood, typically after Step 7. Monitor students during note-taking and address any misconceptions. For weaker learners, simplify explanations and provide more direct guidance. Encourage faster learners to explore advanced aspects or practice the technique more extensively.