This week in class we were tasked with making yet another box, but this time using plywood cut on the laser cutter. It had to be at least 4 inches in each direction and snap fit together without using glue.

I originally tried to use the new laser cutter, but after spending about and hour trying to figure out why it wasn’t engraving, I spoke to a lab assistant and they recommended I use the old laser cutter because the new one hasn’t been reliable lately.

I spent a decent amount of time figuring out the  kerf that turned out to be the curve that was already inputted into makeabox.io, about 0.0025 inches. I found that 3 speed, 100 power, and 10 frequency worked best. I realized the wood was warped, so I placed weight down so the laser would be able to cut through. It turns out that I wasn’t great at placing the weights and the laser only cut through the piece with my name and class engraving and the piece directly in the middle.

Instead of going through with a second pass, I decided to use the ultrasonic knife; I was worried that a second pass would char the edges and possibly cause my box not to snap fit. I spent a grueling 30 minutes trying to meticulously remove each piece from the wood. Some on my pieces got messed up though while  was using the ultrasonic knife, so I decided to recut those pieces and properly place the weight so the laser would cut all the way through.

I finally ended up with 6 pieces I was satisfied with, so I crossed my fingers and put my box together. Everything fit as planned, but some of the pieces weren’t as flush as I liked because of the inaccuracies of the ultrasonic knife, so I sanded some on the pieces down a bit.

After sanding, I put the box back together and I was finally pleased with the snap fit! I added a clear coat to preserve the finish the laser cutter left.

The cost of the wood was about $14; 1/4 in x 4ft x 8ft plywood at Home Depot is $28.42, and I used about half of that size. I used the laser cutter for about 30 minutes, and the cost of using the laser cutter per hour is $0.15, and $0.15/2 =  $0.08. I used the ultrasonic knife for 30 minutes, and at about $400 total, I would estimate my cost of use to be about $2.  I also used sandpaper a small piece of sandpaper, which costs about $1. I spent about 2 hours and received help from a lab assistant for about 15 minutes, and at $10 and hour that totals to $22.50. Adding everything up, the total comes out to $39.58.