The Impossible Dovetail Puzzle

Contributed by
Brian Wetzel, Computer Technology Teacher

Duration: 3 hours plus print time
Level: Intermediate
Resources: CAD program

closed
open

Introduction

This simple model is based on a common woodworking project that, at first glance, seems impossible to un-assemble. The puzzle begins with the two pieces together, forming a cube. The goal is to separate the pieces. The key is knowing that it is actually a combination between two magnets and a steel ball preventing the two halves from sliding apart, not the impossible dovetail joinery.

Classroom Applications

There are many lessons or uses for the impossible dovetail puzzle in the classroom. I have listed a few of the modeling techniques and/or other ways to use the puzzle in classroom below:

Modeling TechniquesPost Printing Uses
Basic Sketches and Extrusions

FIllets

Creating Loft Between 2 Sketches

Mirroring Tools

Offsets

Introduction to Magnetism Units in Science

Recess/Freetime Activities

Family Game Nights

Instructional Units

For each of the modeling techniques above, I have estimated times for teacher demonstrations and student modeling.

TechniqueCorresponding ImageTeacher Demo(min)Student Modeling (min)
Basic Sketches and Extrusions
basic
10 -1515-20
Fillets

fillets
5-1010-15
Loft

loft
15-2525-35
Mirroring
mirroring
10-1515-20
Offsets

offset
5-10

10-15

Index
Support