I have done laser cutting once before for my ENGI 120 project, but it was mostly the TAs operating the machine for me so I basically had to relearn how to use it. I thought this project wouldn’t take that long compared to the previous ones, but it required way more patience and effort than I anticipated.
Procedure
The most crucial part of this project was deciding which kerf value to use, so that the six sides of the box can perfectly fit in. I first tried cutting out a rectangle with 8 lines inside (as it was mentioned on the guideline) to see how much wood is removed by the laser cutter.
This gave me the kerf to be 0.01”, so I printed out two sides of the box with this kerf value to check if they fit in well. But it was not even close to fitting, so I increased the value. I tried 0.012”, 0.015”, and 0.017” but it got worse as it increased. It was interesting to see that the higher the kerf value was, the tighter the joints were (or smaller the gaps were). I thought the kerf value would be proportional to the degree of looseness, but it was the other way around.
(different kerf values I tried)
Anyways, someone recommended me to try 0.004” and when I test printed two of the sides, they fit very well (as in the image below), so I decided to proceed with that.
Then I added the college crest and my name on the box sketch and laser cut everything. However as soon as I assembled everything, I realized the joints were a bit loose and one of the sides kept falling off.
(first trial)
So I tried with the kerf size 0.005”.
(second trial)
All the joints fit much better, but I wanted to improve the quality of the etches (it had a lot of burn marks) so gave it another try by decreasing the power and increasing the speed of the laser cutter a bit. I also converted a picture of my dog to an svg file and added to one of the sides. Before starting printing, I added tapes on the wood to prevent the burn marks.
After assembling all the pieces again (I used the same kerf and wood as the second try but I don’t know why it was way harder to assemble them) my box was finally done!
(final box!)
I wish my dog could be more clearly seen; the svg converter had limits on file size so I wasn’t able to use a better image that I had. Also, the laser cutter somehow didn’t recognize the top part of my dog’s head and didn’t print the lines that were originally on my svg file. But overall, I am happy with what I got.
(the original picture and how it came out)
Now that I know the whole procedure of laser cutting, I want to try printing out other pictures I have when I find the time to do so. I saw the samples of images that are printed out with laser cutter and they looked super cool.
Cost Analysis
- 96 sq inches out of 1/4 ” x 4 ft. x 8 ft. plywood (Home Depot): $ 0.6
- masking tape (Amazon): $ 0.6
- labor: $13/hour x 6 hrs = $78
- TOTAL: ~$79 + additional cost of running the laser cutter
