Surface Treatments And Finishes
Overview
Two identical steel gates are hung on the same day. One was wire brushed, degreased, primed and given two coats of paint. The other was painted straight out of the workshop because the job was late. Both look the same on the day. Eighteen months later the second gate is lifting in blisters and rusting underneath, and the paint on it was the same paint. The finish did not fail. The preparation did.
This lesson takes surface treatments and finishes as the specification does: as preparation and application, applied to enhance functional and aesthetic properties. You will learn printing, embossing and ultraviolet varnishing for papers and boards; painting, varnishing and preserving for timber based materials; dip coating, powder coating and galvanizing for metal based materials; and polishing, printing and vinyl decals for polymers. Each one is a decision with a cost, and the questions on this topic ask which finish and why. This is the last of the nine specialist technical principles, examined in Section B of Paper 1, and it appeared on the specimen paper as a column of its own.
Objectives
- The preparation and application of treatments and finishes to enhance functional and aesthetic properties.
- Papers and boards (printing, embossing and UV varnishing).
- Timber based materials (painting, varnishing and preserving).
- Metal based materials (dip coating, powder coating and galvanizing).
- Polymers (polishing, printing and vinyl decals).
Mind map
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Surface Treatments And Finishes. 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.
- Galvanizing protects steel because zinc A. is harder than steel. B. corrodes in preference to the steel. C. is a better conductor than steel. D. is cheaper than paint. Answer: B
- Which finish is applied to papers and boards to give a hard, high gloss, scuff resistant surface? A. Dip coating B. Embossing C. Preserving D. Ultraviolet varnishing Answer: D
- In powder coating, the powder is attracted to the part because it is A. heated until it melts. B. dissolved in a solvent. C. given an electrostatic charge. D. sprayed under high pressure. Answer: C
- Which treatment is used on timber that will be in contact with the ground? A. Embossing B. Polishing C. Preserving D. Powder coating Answer: C
- Which finish for polymers requires no tooling and can be removed and replaced? A. In-mould decoration B. Pad printing C. Screen printing D. A vinyl decal Answer: D
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Work through these questions in the app
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