Introduction
In this post, I detail how I used the laser cutter to produce a box that can snap, assemble and hold itself together without an adhesive. I worked with Winson on this assignment, but we each produced our own box.
The constraints of the box comprise:
- minimal to no charring;
- the edges should be clean; and
- the part should have the correct geometry.
preparation
Materials and Tools:
- Plywood
- Laser cutter
- Adobe Illustrator
- Caliper
measuring the kerf
First, we sought to measure the kerf (the amount of wood burned when cutting) of our respective laser cutter. To do this, we cut out the provided KerfBox file and push the rectangles against each other, creating a gap between the last rectangle and the border. We then measured the amount of space with a caliper and divided by the number of wood slabs.
Measuring the kerf.
Our measured kerf using this method was 0.142″, which divided by the 10 slabs equals 0.0142″.
tuning the laser cutter
Next, we sought to obtain the best cut settings for our laser cutter to minimize charring while ensuring it would cut through the wood. To do this, we cut a 0.25” x 0.25” square to see whether our cutting settings were set correctly.
Boxes to test cut settings.
Our best settings for cutting were 85 power, 6 speed, and 10 frequency.
designing our box
Then, we used en.makercase.com to generate a box design. We specified our box to be 4” x 4” x 4”, tabs of .75″, specified finger joints, and then input our measured kerf. We put this generated model in Adobe Illustrator and used the shape builder tool to combine the squares into 6 shapes. I added text to the front of my box, using Arial Black font, and imported and placed my college crest (Jones) on the back of my box.
Illustrator file, ready to laser cut.
Cutting the box
Iteration 1
First cutout of the box.
At this point, we realized we had forgot to use calipers to measure the thickness of the wood and enter that into makercase. Therefore, the sides did not fit flush with eachother.
Sides did not fit flush.
In addition, the etching settings I used (20 power, 80 speed) was too light. The kerf was also too small, so the joints did not fit.
Therefore, I changed the thickness of the wood to .19in from .118in and the kerf from .0142 to .0147 in Makercase, and adjusted the etching power to 30.
iteration 2
After making these adjustments, I proceeded to cut my box out again.
Second cutout of the box.
When assembling, the kerf was still off and the joints did not fit well with eachother. I managed to attach the sides using a lot of force. While doing this, one side of my box split.
Broken front side.
I recut this front piece with higher kerf (0.015), and the new piece was able to fit better with the rest of the box.
Finished box (1).
Finished box (2).
Clean workspace
Cleaned workspace.
Cost analysis
Wood ($36.08/panel) – $6.01
Labor (2 hrs at $10/hr) – $20
Laser Cutter Use(2 hrs at $0.10/hr) – $0.20
Total Cost: $26.21
Conclusion
Overall, I felt that I was very thorough in getting the laser cut settings correct and conserving material. I think my box looks fine aesthetically but am not completely satisfied, since it was hard to put together as a result of the incorrect kerf measurements. I will look to resolve this descrepancy when laser cutting for the midterm project.
