We are back again with yet another fun project for my class. This time, we’re making a box out of wood on a laser engraver! This project involved designing a box that can be put together without the use of any glue, tape or other fasteners. In order to accomplish this, a tight fit between the pieces must be achieved. I used an online box designer (https://www.makercase.com/#/basicbox) to aid me in the design of my box. After playing with the settings, I settled on a 4″x4″x4″ box with finger joints 0.55″ in width. This maximized the number of joints per side and looked nice in my opinion. After adjusting the kerf to be 0.014″, I exported the files as an SVG.

Once the file was ready, I began testing the Kerf of the laser engraver that I wanted to use. This was done by cutting out the Kerf testing file provided to us. Once cut, I measured the gap in the boxed area to be 0.11″ meaning that the Kerf of the laser was ~0.01″. With this result in mind I decided to take note of the settings used so I could cut out my box.

Now that I found the Kerf, I decided to print out the rest of my box. I changed the print preferences to get the best quality results, or so I thought. I sent the print to the laser engraver and let it rip! The engraving turned out quite well but when I tried to assemble the box, I noticed a big issue.

The joints on the box had a very slight overlap and made it extremely challenging to assemble the box. Additionally, I needed a hammer to assemble the box and ended up damaging a few on the joints in the process. This indicated that not only did I use the wrong Kerf, but my laser settings were off too! While this was quite disappointing initially, it did mean I got to test out some more settings.

After playing with the laser settings, the kerf, and a slew of print errors, I finally got two panels to fit together perfectly! I tested each iteration with two sides of the box, incrementally adjusting the kerf and laser. The settings I landed on were a digital kerf of 0.013″, 6% speed, 100% power, and 10% frequency. For the engraving, I used 50% speed, 60% power to get a nice color on the wood. The resulting panels fit together with a little bit of force, but this was doable with just my hands.

With these settings, I set my the new print and got to work. The final result was a box that was press fit and very secure. In the end I’m glad that I made so many mistakes. I have done a lot of laser engraving in the past, but this project taught me some skills that I didn’t know that I needed.

Cost Analysis:
Plywood- $24.99 for 24 sheets, ~$1 per sheet (used 1 sheet)

Labor- 3hrs at $7.25/hr – $21.75

Total Cost: $22.75

After the project I cleaned up  my workspace. There was a club or other group working on their project nearby, but I cleaned up as much as I could.