Personal Making Assignment 3: Digital Making - Press Fit Kit

This assignment is due in 2 weeks to account for time needed on the laser cutter. Please start early!

In this assignment, you are to use the laser cutter to make a press fit kit: an assembled 3D structure that works through friction fit joints and requires no adhesive. The goal of this assignment is to gain familiarity with the CAD-CAM cycle and digital fabrication processes. As such, in addition to your final object (and to get you to practice for Proj 1), you will also be submitting a write up and documentation of the design process as you go along.

In your documentation, please include

  • Intermediate photos of the process, including
    • A screenshot of your vector file
    • (Optional but highly recommended) photos of any test cut pieces you did
    • A photo of your pieces cut out and laid flat
    • Photos of your pieces assembled in at least two different ways. You can have a “final vision” or intended object, but you should also show an alternate way the pieces can be fit together, even if it isn’t in line with your vision.
  • Settings: What power and speed settings did you use on the laser cutter? Did you have issues with fires or scorching?
  • Acknowledgements: List any online resources you used, modified, or got inspiration from. List any people (such as makerspace stewards) you got help from.
  • Reflection paragraph: How did this assignment match up to your initial expectations? What was the most challenging part? What did you learn about interacting with fabrication machines? Were there any parts you had to redo, or lessons you learned for the future?

Remember, the thickness of your slots will be determined by the thickness of the plywood you cut. Every piece of plywood is different so it’s very important to take accurate measurements with a caliper.

Tips & Resources

  • Start early. There might be a queue for the laser cutter, and it’s best to go when a HMC makerspace steward has laser cutting experience on duty. Here’s the makerspace schedule.
  • As always, prototyping and iteration. You can use paper or cardboard to cheaply play with general shapes you would like to make before you cut into your plywood sheet. When measuring your material thickness, I would make a few variations of your connectors with ± 0.2mm differences and cut those out first to find the “ideal” fit.
  • Remember that the plywood boards are around 12 x 17.5 inches. Make sure your pieces can fit within a single plywood board.
  • Press fit kit construction tips from FabAcademy. Make sure to chamfer your connecting slots!
  • A laser cut press fit kit is a pretty common project in fabrication based courses, like MIT’s “How to make anything” or UW’s HCDE598. Googling the term will give you many student project blog posts that you are free to use as inspiration. You must credit their work if this is the case.
  • This Instructables offers one possible starting point–though you should modify it (and credit it) if you end up using it. The files are in .dxf, but you can import them in Inkscape and resave them as .svg.

Grading & Submission

You are submitting two files to Canvas: A PDF that contains:

  • Documentation of your process through text and images. Take intermediate photos of your process: include at least one screenshot of your vector file, one of your pieces cut out and laid flat, and two photos of your kit assembled into at least two different shapes.
  • In addition to documenting the pieces, include at the end of the PDF your process written overall reflection paragraph.
  • Bring your assembled piece to class on Thurs 2/15 for critique.

Additionally, submit the vector file (.svg format) you used for laser cutting.

Estimated/expected time: It is my hope you spend no more than 6 hours on this assignment. Ideally, you will spend no more than 1 hour creating and cutting test joints to find the right joint size for your piece of plywood, and then 2 hours designing and cutting the parts, 1 hour assembling the parts, and 1 hour for the write up and reflection. Add another hour in there for iteration.


  • ✓+ : Students made an intricate press fit kit object, and wrote a thoughtful process and overall reflection
  • ✓ : Students made an original press fit kit object, documented the process, and wrote a thoughtful reflection
  • ✓- : Students took an existing press fit kit on the internet without modifying it, or have poor quality process documentation/reflection