Joining
Overview
A product is rarely made from a single piece of material. Sooner or later parts must be held together, and how they are joined decides whether the product is strong, whether it can be taken apart for repair, and how it looks. Joining is the craft of bringing materials together permanently or temporarily using the right joint, fastener, adhesive or heat process for the materials and the demands placed on them.
This note covers joining across woods, metals and polymers: framing and carcase joints in wood; the difference between permanent and temporary joints; pre-manufactured components and fasteners such as screws, bolts, rivets and knock-down fittings; adhesives matched to each material; and the heat processes of soldering, brazing and welding. It explains how to choose, because a join that is strong in one situation is wrong in another.
Objectives
- select and use appropriate methods of permanently or temporarily joining materials, for example: - joints - pre-manufactured components and fasteners - adhesives - heat processes.
Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Joining. 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.
- Which wood joint is strongest for the corners of a chair or table frame? A. Butt joint B. Mitre joint C. Mortise and tenon joint D. Plain glued lap Answer: C
- What is the main advantage of a knock-down (KD) fitting? A. It forms the strongest possible permanent joint B. It allows a product to be flat-packed and assembled or dismantled with simple tools C. It welds the materials together D. It is only used on metals Answer: B
- Which adhesive is correct for permanently joining two pieces of acrylic? A. PVA wood glue B. Solvent cement (e.g. Tensol) C. Contact adhesive D. Hot-melt glue Answer: B
- Which fastener is best for permanently joining sheet metal when only one side is accessible? A. Nut and bolt B. Wood screw C. Pop rivet D. Dowel Answer: C
- What is the key difference between welding and brazing? A. Welding uses no heat B. In welding the parent metals melt and fuse; in brazing only the filler melts C. Brazing is always stronger than welding D. Welding can only join plastics 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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