How to Build a Laser Cut Display Case | ENGI 210: Prototyping and Fabrication

Being fairly familiar with Adobe Illustrator and comfortable using the laser cutter, I decided to push myself to create something extra for this assignment.

Full disclosure: for this project I was heavily inspired by this video of an acrylic display case with a openable door. But I decided to add my own modifications to improve it and make it my own.

I started out by sketching out the parts from the video from scratch in Illustrator. This video had some neat tricks on how to do that. I made sure to utilize different layers so that I could easily hide/show different parts and keep track of what was cut on the same sheet of plywood.

Afterwards, I wanted to make sure this concept would actually work, so I decided to make a mini version out of wood before cutting any acrylic and adding my own modifications. Since for the top part of the case I was using holes rather than finger joints, I wasn’t entirely sure how to take into account the kerf of the laser, and just decided to run some quick fitting test cuts.

This was the first iteration of the case:

I did have to sand down only some tabs for it in order to fit into the holes, which was a bit strange because in Illustrator they were all the same size. I noticed that during the cut the large piece was being cut first, then the holes which might have been the issue since after the large piece was cut from the plywood it dropped down which might have messed with the height calibration.

PRO TIP #1. Ordering in Illustrator matters. Whatever is on the bottom layer will be cut first. I recommend cutting out the holes before the large piece.

Now that I had a working proof of concept, I wanted to add in a shelf in the middle of the box. I remembered seeing something about using engraving functionally rather than decoratively to carve out as a slot to hold a shelf, so I tested that concept out on a smaller box (to save some wood). During this iteration I also had the idea of adding a little notch on the opposite side of the hinge to hold the door in place so that it wouldn’t swing freely when lifted and moved around.

Overall, it turned out quite nicely, although I had to do some sanding to get the shelf to slide in properly.

These were my laser settings on the Fusion M2 for the small box:

One thing that was very frustrating was that even though in Illustrator the walls, tabs, and holes were all the same width, after cutting there was a noticeable difference between some of the pieces.

I think this was due to a combination of factors. One being the warping of the wood, the other being the direction of the grain of the wood. I noticed that the pieces following the grain of the wood were slightly shorter.

PRO TIP #2. When cutting out pieces which you need to be the same length, try to cut them in the same grain of the wood, and cut them out individually utilizing weights to minimize warping.

Lastly, it was time for the final build. I didn’t have access to the acrylic sheet until this point, and after I got it I realized it was considerably thicker than the wood, which meant that I would have to adjust the hole sizes to be larger. I measured the difference using a caliper get a baseline and ran some quick tests using different hole sizes. It was definitely a time-consuming process of manually adjusting the sizes in Illustrator.

During this test I also tried out engraving the slot on the acrylic. But I ran into a problem. Even at the recommended power & speed settings for acrylic it barely engraved the surface, which meant that for the final build I would have to run the raster cut multiple times for it to be deep enough to hold an acrylic sheet. In the end, I made an executive decision to not add a shelf since I was running low on time.

For the final build I also wanted to add a base to the display case. For this, I just used a basic online box maker onto which I edited on the holes from the base piece in the first 2 versions.

I made a quality of life change of rounding out the edge of the door panel. I also adjusted the hinge holes a bit to be bigger after I accidentally broke off a piece of the acrylic after rotating the door too forcefully (rip).

Here’s a bit of a closer look at the door locking mechanism. I intentionally designed the door panel to be marginally shorter than the other panels so that you have to lift it a bit to get the small bump out of the hole in order to be able to rotate and open the door.

And that’s it! It has a bit of a blender vibe to it but overall happy with the result. In the end, I guess I ended up making three different builds that show the iterative process.

After this I sanded down the base box a bit with the orbital sander (330 grit) but the vibrations ended up loosening the finger joints a lot, so the final build is a bit unstable 🙁 I’ll likely have to glue the base together or cut out an entirely new base, but that’s for a later date.