Finishing
Overview
A product is not finished when the last cut is made. Bare wood absorbs water and stains, bare steel rusts, and a rough surface looks unmade and feels unpleasant. Finishing is the final stage that protects the material from its environment and makes the product look and feel the way it should. Choosing the right finish, and preparing the surface properly first, is what separates a workshop exercise from a product someone would buy.
This note covers finishing for woods, metals and polymers: protective finishes that defend against moisture, corrosion and wear; decorative finishes that change colour and appearance; the all-important surface preparation that every finish depends on; and the idea of self-finishing materials such as acrylic and many polymers that need no added coating at all. It explains why each finish suits its material and how to match the finish to where the product will be used.
Objectives
- select and use appropriate finishes for materials including: - decorative finishes - protective finishes
- show an understanding of self-finishing materials.
Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Finishing. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- What is the main purpose of a protective finish on mild steel? A. To make the steel heavier B. To form a barrier that keeps oxygen and moisture from the metal so it does not rust C. To soften the metal for bending D. To make the steel conduct electricity Answer: B
- Which material is described as self-finishing? A. Mild steel B. Natural softwood C. Acrylic (PMMA) D. Cast iron Answer: C
- Why must a surface be properly prepared before a finish is applied? A. Preparation is only needed for metals B. A finish over a dirty or greasy surface will not key and is likely to peel or look patchy C. Preparation makes the finish unnecessary D. It changes the colour of the finish Answer: B
- Which finish protects steel sacrificially, still working even if the coating is scratched? A. Clear lacquer B. Wood stain C. Zinc plating (galvanising) D. Danish oil Answer: C
- Which finish would best suit outdoor timber that needs to resist rot and weather? A. Sanding sealer only B. A preservative plus an exterior varnish or oil C. Polishing D. No finish, as wood is self-finishing Answer: B
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Recommended Books
Practice Mock Questions
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