W2 -- Laser Cut Box

For my project, I wanted to get familiar with the Autodesk 360 software by making a simple open box. I also had the goal of constructing something that would hold snuggly together without glue, assuming I was able to find the right kerf for my parts.

I first did some research into different types of joints to hold wood pieces together, and learned about the dovetail joint method. See images above from an article on finewoodworking.com by Chris Gochnour. This type of joint holds strongly without glue, but it requires one piece of wood to have pins formed which are angled along the same axis as the laser cutter, so manual chiseling is required after the laser cuts are made. I wanted to avoid the manual step and so opted to design walls which would have simple, straight pins and tails. This would be less strong than dovetail joints, but would be possible to achieve with the laser cutter, and hopefully with the correct kerf would provide some hold.

For the base of the box, I wanted to use a different method to join the base to the sides as my intuition told me that the straight sided dovetail-esque joints wouldn't be strong enough to hold on a 90 degree angle. I decided to create tabs which stuck out from each side of the base which would slot into holes near the bottom of each wall. This way, the base was resting on the slots of each side piece. From there, I made a rough initial sketch of the three different pieces I would need to make (with the two different side pieces being duplicated).

From there, I translated to Fusion 360, using similar techniques to those we had learned in class including extrusion to make holes as well as circular and rectangular patterns. Since I was using Fusion 360 for the first time, it took me quite a while to figure out the basics like centering objects, making sure that the matching features were at the same height to each other, and simply moving objects. At the end, I realized I needed to adjust my measurements for the length of the sides. I had initially assumed that they would be the same length as the sides of the base, including the joint tabs. Towards the end, I realized that the joint tabs needed to extend past the length of the base, since the sides sat along the exterior of the base, not on top of it, and made this adjustment. I found the process to require a lot of thinking about how each piece would fit together once assembled, and wanted to be able to temporarily manipulate the orientation of each piece relative to each other so I could test out assembly in the editor.

I first created a couple of test pieces which had tabs the same size as my short and long walls to test that the walls would fit together correctly. I used a kerf of .2mm, which fit very snuggly. Since I wanted the box to hold together and didn't plan to take it apart, I printed the rest of the box using this kerf.

In assembling the whole box, I realized that I would have had an easier time with a slightly smaller kerf, as it took some effort to push everything together. Once the box was assembled, it does stay together very well.