# Stereometry

Stereometry is a branch of mathematics for three-dimensional solids and the relationships between them. When a plane intersects a cube, there are a variety of shapes of the resulting cross section. In this lesson, students will learn how to construct a cube cut in a free parallel projection before recreating the resulting polygon (cross section) in CAD.
Subjects
Design and TechnologyScienceMathematicsComputingMasaryk University
Duration
Lesson 1: 90 minutes Print Time: 1-2 hours
Stereometry trailer
Play 0:41

### Objectives

• Construct a cube cut in a free parallel projection.
• Construct a section polygon in its actual size.
• Check the result on the 3D model by selecting the correct polygon.
• Construct the result using TinkerCAD software and print a 3D model of the cube.

### Tools and equipment

• BE3D eDee printer
• Example 3D polygon models and 3D printed cube
• Internet enabled computer and TinkerCAD®
• Printed lesson resources

### Skill requirements

To participate in the lesson, students should be able to:
• Use TinkerCAD, Fusion 360 or similar CAD software at an intermediate level
• Be comfortable using DeeControl software including adjusting print settings
• Use the BE3D eDee 3D printer
Stereometry walkthrough
Play 1:53

## 3D models overview

• Total print time 13 hours 30 minutes
• Total filament 51 m
• Printed all at once
Cube bottom
• 5 hours 30 minutes
• 12.4 m
Cube top
• 2 hours 45 minutes
• 8.7 m
Triangle
• 1 hour
• 6 m
Hexagon
• 1 hour
• 6 m
Square
• 1 hour
• 6 m
Rectangle
• 1 hour
• 6 m
Trapezoid
• 1 hour
• 6 m
Note: Values are calculated for one set of models.

### Lesson resources

• Lesson plan
• Example 3D polygon models and 3D printed cube
• Worksheet
• Walkthrough
• Presentation
• 3D models
• 3D print instructions
• Curriculum alignment