Week 2: Computer-Controlled Cutting

Part I: Vinyl Cutter

The CBA shop has Cricut Maker 2 vinyl cutters. This took relatively little effort after downloading the cricut software and making an account. I didn't want to pay for a design or sign up for a 30-day trial so I just cut simple text sticker for my laptop. Here is the chat I had with Gemini about vinyl cutting.

Image of HTMAA sticker on transfer tape.
Sticker on transfer tape.
HTMAA sticker on laptop.
Sticker on laptop.

Part II: Laser Cutting Monotile

This part took an entire day, mostly because I chose to use an aperiodic monotile to build a 3D structure. Also known as Einstein hats, this was the first discovered pattern able to infinite non-repeating tiling. Each monotile is composed of eight "slices" of a regular hexagon, which makes it easy to create in CAD by mirroring three times.


Hat aperiodic monotiles.
The first aperiodic monotile was discovered in 2023 by David Smith.

I initially created a comb to measure the kerf and notch width and settled on 3.5 mm notch width. I had to cut multiple combs since the cardboard I had at home differed in thickness from the cardboard at the shop but parametric parameters made this relatively simple to change the starting and ending widths.


Image of cardboard comb.
Comb with varying notch widths from 3 mm to 4 mm in 0.05 mm increments.
Image of connected cardboard comb at 3.5 mm notch width.
3.5 mm ± 0.2 mm seemed to work well for fitting.

I created a sketch of the monotile and joining circular tiles in Fusion. Because of the non-repeating nature of the 2D pattern, I didn't have a pre-planned design for the 3D structure and make several angles to experiment with. I ended up using the 120° angle the most. I found that 80% power and 30% speed worked well for the 4 mm cardboard I was using on the Epilog laser.


Here is the CAD file.

Image of monotile lasercut pattern.
Monotile lasercut pattern.
Image of monotiles.
Cut monotiles and connectors.

I tried forming 3D structures out of repeating subpatterns but (unsuprisingly) could not get any repeating structure.


Unassembled pattern of three monotiles.
Unassembled pattern of three monotiles.
Assembled pattern of three monotiles.
Assembled pattern of three monotiles.
Unassembled pattern of six monotiles.
Unassembled pattern of six monotiles.
Assembled pattern of six monotiles.
Assembled pattern of six monotiles.

Some tips:
  1. Tape the cardboard so it doesnt move in the lasercutter
  2. Add chamfers to all joints. I only chamfered the monotile
  3. Check the direction of the cardboard before cutting since it is directional material.

Part III: Making a HTMAA Website

I modified Kai Zhang's well designed website with some minor modifications such as changing the background color to cosmic latte and adding figure captions".