03: Rapid Prototying
7/3/19 – Laser Cutting and Vinyl Cutting
Today during our lab, we were instructed to make a press-fit construction kit from laser cut shapes that interlock together. I decided on using a triangle for my base piece in the construction kit because there are many 3-D modular solids that are solely constructed from triangles.
I wanted to make a triangle that wasn’t basic, so I modified the triangle by curving the sides. This was my first attempt of designing the triangle in fusion: However, I then realized that I had put the slots for connecting the triangles together in the wrong place– they shouldn’t be on the vertices, but instead on the edges. I then adjusted my design accordingly:
Next, I decided that I wanted to make an icosahedron, a 20-sided solid figure, out of my triangle faces. I wanted the triangle faces to be held in place solidly, so I designed a connector for the faces that would hold the triangles in a proper angle. I used this list of dihedral angles and the Wikipedia page for the icosahedron to get my measurements. The dihedral angle between each face is 138.19º, so that is what I used for my connector:
I came into class the next day with my files ready for cutting, but I hadn’t properly accounted for the kerf. After cutting a test round of 2 triangles and a connector, I measured the kerf, and it was 4mm total. I then adjusted my design accordingly to account for the kerf, and the pieces then fir together well. In total, I ended up needing 20 triangles and 30 connectors. When my pieces were ready for cutting, I copy and pasted an array of these shapes within the laser cutter software, and it cut pretty well.
Then I assembled the icosahedron, and it turned out perfectly! I’m very happy.
Click here to download my triangle piece file and click to download my icosahedron connector file
I then wanted to try vinyl cutting to make a sticker. From an explanation of the vinyl cutter by Professor Hart, I learned that the vinyl cutter uses a rotating knife to trace vectors of an image to cut it out. I wanted to make a sticker of the character Miffy, so I first found a simple image for the vinyl cutter software to interpret. Then, after inputting it into the vinyl cutter software, these were the interpretations of the image:
I loaded the vinyl cutter with green vinyl by lifting up the back lever and then moving the wheels to the edge of the material.
My stickers ended up being super accurate to the original image and looked amazing! Now they have a permanent home on my laptop.
I really enjoyed working with both the laser cutter and the vinyl cutter, and am excited to do more in the upcoming sessions!