Week 2: Laser Cutting
burn baby burn!

The Assignment

a press fit kit

I was very excited to learn about laser and vinyl cutting. The precision that one can achieve by feeding a file to a laser or vinyl cutter demonstrated to me why I need to work on my CAD skills. If you can make a good design, these machines can turn them into reality very quickly and effectively.

Our assignment was to make a pressfit model using the laser cutter. Because of the precision that the laser cutter can achieve, you can design pieces that can simply be cut out a pressed together and they will hold their form in a joint. COOL!

What to cut and press?

sharp questions

We've been given cardboard to cut out our pieces with (like a Lego set). This thick cardboard is flat, sturdy, and cheap making it a good material for us.

But, I also wonder if laser cutting can be used on bamboo? And if so, could this pressfit method be used to create joints between bamboo culms? I want to use this assignment to see how round, highly variable (+/- 3-10mm) bamboo culms might be used with a laser cutter.

I'm also fascinated by the different kinds of joinery that were illustrated for us during the lecture. A simple pressfit joint can be altered in ways to make it more reliable or even provide for freedom of movement. How can joints be designed for strength and movement?

The Design

parametric for quick adjustments

I used InkScape to make a model for a piece that should be able to lock in with pincers at the end(left) because I believe this design would also work well with bamboo slats.

I quickly discovered I made a mistake in were to locate the locking pincers and that the thickness of the cardboard wasn't correct, but because I had cloned the different elements of the piece, I was able to make adjustments on the fly.

Rather than planning out what the final object would look like, I wanted to make a whole set of "building blocks" and then see what I could do with them.

Trial and Error

two at a time...

It quickly became apparent my inexperience at press fit joints would require a lot of trial and error. Without going into detail, I'll list just some of the iterations I did:

  • joints were located on same axis weaking the tile
  • locking pincers were too tight
  • notches were wider than cardboard
  • notches were not symmetric so building was challenging
  • forgot to run laser cutter twice to fully cut out the piece
  • not setting the line weight so the laser cutter wouldn't move
  • leaving too little cardboard between cut outs so the cardboard fell apart
  • leaving too little cardboard between cut outs so the cardboard fell apart


building the building blocks

I brought the tiles out of the workshop and to a lounge. I began playing with the pieces and other people began to be interested in it.

It's amazing how much people love being given easy-to-use pieces to make something original. "This is awesome! You can save so much money and just make your [future] kids' Legos!" was one response. Even though the structures were not as cool as I thought they might be it was still very fun to put them together. I was especially proud of the pincer locking mechanism so that each tile can not only be presed together but locked in. In the future, I hope I can expand on this system to strengten the joint to support enough weight for perhaps a bike rack, bike frame, or even foldable bike...

A laser cutter probably would not be able to quickly make something like this.

Learnings and Reflections

still no bamboo...

It was fun playing with the building blocks that I cut out, and it helped me understand how the laser cutter can be used, but it did't help solve my question of how to use bamboo with it. Because of time restraints, I haven't had time to bring in some bamboo slats for trial but these are some of the challenges that I anticipate:

  • Because the laser needs to be focused on what it's cutting, this will mean that I can only cut bamboo laterally (with the grain) as the height of the rounded surface will remain constant
  • Zeroing the laser on a small piece of bamboo requires double checking the origin with piece of bamboo first and then placing the bamboo
  • Bamboo walls vary in thickness which makes it diffiuclt to make pressfit systems.

With this in mind, laser cutting might be useful for work on bamboo laminate but not on the raw material itself. These laser cutters are great for flat and standardized materials, but they would need a deeper understanding of the material its working with to work with bamboo or other natural materials.

How To Make (almost) Anything
MIT Media Lab MAS863.15