I had already used the laser cutter for box-making on several occasions, so for this assignment I chose to make some display shelves instead. I used this example in the wetlab as inspiration:
I really like the modularity of these shelves, so as more examples get made, more spots can be added to display them. I decided to mimic this, but go with a slightly simpler design, using squares instead of more complex shapes. So I opened up illustrator and made a basic square platform, 4 inches by 4 inches. Then, I made a small (~1.5 in) connecting bracket. I added 5mm slits so they would fit together with the wood (I know, switching from imperial to metric is weird, but the wood was exactly 5mm when I measured it, which is a way nicer number to work with than 0.19685in!)
Illustrator drawings of connector (left) and platform (right)–– NOT to scale (obviously…)
Then, I test cut three platforms and one connector on a piece of scrap wood, just to see if I got the right tolerance for the kerf. My pieces were pretty loose, so I decided to use 4.5mm gaps instead of 5mm gaps–– I wanted the fit to be as tight as possible without damaging the wood. The 4.5mm version worked, so I cut 19 connectors and 12 pieces of wood (it should have been 18 connectors, but one of them was on a knot in the wood and so it wasn’t thick enough). All of my cutting was done on the new laser cutter–– I used tape to avoid burnt edges, and used the camera to position my cuts right over the tape. I experimented with settings some, and found that doing one pass at 20 speed, 100 power, and 10 frequency usually worked, and when that wasn’t enough to go all the way through the wood, I changed the speed to 55 and did a second pass. In one instance the laser cutter didn’t cut through and I moved the wood so I was afraid to do a second pass since I might not be able to align it perfectly; I cut the piece out using the ultrasonic knife at the makerbar.
After all my pieces were cut, I moved on to rastoring. I made a google doc, typed my text, then screenshotted it and imported it into illustrator before cutting. I did three test cuts: 50, 60, and 70 power at 100 speed. I liked the 60 power cut best, so I etched onto one of my platform pieces using those settings.
Here’s the finished product! The fit is really tight, which I like. Initially, it was rocking a bit, so I filed down some of the connector pieces on the bottom to level it out, and then added a thin layer of hot glue to keep it from scratching whatever surface I rest it on. I like the texture of the wood a lot, so I decided not to finish it.
My favorite part of this display set is its modularity, just like the example in the wetlab. Now that I have the files, it won’t take long at all to add more shelves as I make more small objects to put on display!
Cost Analysis:
- All wood used was scrap– $0
- Labor, assuming $11/hour OEDK lab assistant cost, for 3 hours of work– $33
Total: $33
