A7: Final Project Proposal: Mexican Finger Surprise Toy


I will build a toy from my infancy using techniques learned and materials used during this quarter.


Growing up in Mexico City, I somewhat remember a small toy with the shape of a box that you could slide open and be greeted with a snake moving quickly towards your finger unexpectedly.

At some point, I noticed that the box had a mechanism connected to the sliding door that would make a small snake figure rotate outwards from the box towards the place you'd put your finger to pull it. The mechanism was extremely simple -- it used a string to pull the snake outwards when the door was slid open, and inwards when closing the door.

I googled some random words, and found something pretty similar:


The intended use case for this box is to scare the curious individual who dares open it.


Breakdown of tasks for the final assignment
Technique Component
3D Modelling + laser cutting Box sides 3D printing,
Mechanism design Mechanism/gear that raises the surprise
3D Printing Critter/surprise
Milling Internal pockets and spaces to place the mechanism



Bill of materials and sourcing schedule for assignment 8
Material Sourcing status
Frosted acrylic Own (leftovers from the lamp assignment).
Filament for 3D printing Have access to it (not officially mine).



Detailed plan and timeline for assignment 8
Tasks Time ETA Date start Date finish
Design box parts 4h 5/27 5/27
Design mechanism to raise surprise 2h 5/27 5/27
Cut box parts 2h 5/28 5/28
Mill box parts for sliding mechanism 2h 6/1 6/1
3D print surprise 2h (active) 5/29 5/29
3D print mechanism to raise surprise 0h (combined with above) 5/29 5/29
Assemble components 2h 6/1 6/1
Testing 1h 6/1 6/1
Re-engineer & re-fabricate parts 3h 6/2 6/2
Document project 2h 6/2 6/2

Update: Sketches and current process as of 5/29