Lesson Overview
Students advance their Shapr3D skills by mastering advanced extrusion techniques and boolean operations. Building on the sketching, dimensioning and constraint skills from Lessons 1 and 2, students learn to combine, subtract and intersect 3D bodies to create complex functional forms that would be difficult to achieve with a single sketch. Students explore when to use Union to merge bodies, Subtract to carve precise holes and recesses, and Intersect to derive shared volumes. The lesson emphasises breaking complex objects into simple primitive bodies — a mindset shift that dramatically increases modelling efficiency. By the end of the lesson, students will recognise boolean operations as a core design strategy, not just a set of tools.
Learning Objectives
By the end of this lesson, students will be able to:
- 1Explain the difference between standard Push/Pull extrusion and multi-body boolean workflows
- 2Identify when a complex shape is best modelled by combining simple primitives rather than sketching a single complex profile
- 3Apply the Union operation to merge two or more 3D bodies into a single solid
- 4Apply the Subtract operation to carve precise holes, slots, recesses and cutouts from a target body
- 5Apply the Intersect operation to derive the shared volume between overlapping bodies
- 6Plan and execute a multi-body modelling strategy: sketch primitives, position them, then apply boolean operations
- 7Model a functional mechanical part that requires at least one Union and one Subtract operation
Singapore Curriculum Alignment
Aligned to MOE Design & Technology (Upper Secondary): modelling strategies, design for manufacturing, and efficient CAD workflows. Supports the Applied Learning Programme (ALP): strategic thinking, design decomposition, and computational design literacy. Boolean operations connect directly to manufacturing concepts like CNC machining, mould-making and assembly design.
Prior Knowledge Required
- Confident navigation of the Shapr3D workspace and use of touch/pencil gestures
- Proficiency with basic sketch tools (line, rectangle, circle, arc) and Push/Pull extrusion
- Understanding of geometric constraints and dimensioning from Lesson 2
- Experience creating simple 3D bodies and inspecting them from multiple angles
Materials & Resources
| Item | Quantity |
|---|---|
| iPad with Shapr3D installed (free education license) | 1 per student or pair |
| Apple Pencil (recommended for precise body positioning) | 1 per student |
| Teacher iPad with screen mirroring to projector/Apple TV | 1 |
| Shapr3D student account | 1 per student |
| Boolean operations quick-reference card (Union / Subtract / Intersect icons and examples) | 1 per student |
| Printed challenge brief with dimensioned reference drawing | 1 per student |
| Optional: 3D printer for printing student boolean models | If available |
Safety Notes
- Maintain good ergonomic posture during extended iPad use — boolean workflows involve repeated tool switching
- Take short breaks to rest eyes and hands during intensive modelling sessions
- Remind students to save versions before each major boolean operation — boolean operations cannot always be cleanly undone
- Keep iPads charged and on flat surfaces when not actively in use
- If 3D printing student models, follow all printer safety and post-processing protocols