For this assignment, I chose to laser cut the 3D Finger Tenon model that can be seen below. I found this one to be interesting, as it seemed like one of the 3-dimensional puzzles that would be fun and interesting to assemble. The photo below shows the drawing file from prototypinglibrary.com

I loaded the file on the laser cutting computer, and was about to cut, before Dr. Wettergreen recommended that we check the power and speed with a small square as opposed to the full shape, to prevent wasting of material. I used Speed 6 and Power 100, which was interpolated from the chart on the wall, and got a square I was pleased with (seen below). There was minimal charring, and no soot residual.

Once that was cut, the next step was to cut the full design. I stuck with the 6 speed and 100 power, and followed the instructions on the board to create my cut. I used 50 speed and 100 power for the etching, which again was recommended based off the chart listed. I placed my material in the bed and began etching, before realizing that there was not enough room in my triangular piece.

I flipped the triangle around to orient the right angle at the upper left corner of the bed, and began cutting from there again. However, this time, I did not realize the laser could be zeroed off the edge of the bed, so I had set my laser origin too high up. When it started etching, not all of the design was on the wood, so I canceled to reset my position.

Finally, the new orientation with the proper origin was a success. Now, we just have to wait ~5 minutes for the file to finish cutting and etching, and hope it turns out OK.

Our pieces cut out are a success! We don’t see the “burnt toast” effect, but a nice golden brown along the edges and in the text.

The last step is assembly. This proved to be more difficult than I thought, partly because of the confusing geometry and that all the pieces needed to be properly aligned to fit together. Furthermore, this design was created for wood slightly thinner than what I used, which meant that some pieces did not fit together easily, and required a bit of force to make a press fit. If this were being done repeatedly, it would be wise to update the drawing file to allow for the different thicknesses, but for this assignment, the slight change in thickness was able to be overcome.

In creating the other piece, even though the wood was the same type and thickness, it required a slower speed to get all the way through the wood. I ended up using 5 Speed and 100 Power, after doing the square test. The first piece had some deformities and gaps that required a faster speed, while the second was more uniform. I learned that even if you have a seemingly identical piece, it is always a good idea to perform a small scale test of the piece to see how it responds.