After completing (or almost completing) my homework over laser cutting, woodworking, 2d drawing, and plasma cutting as well as my seminar on water jet cutting, I was ready to start on my midterm project. This project involved using mechanical movement to create a simple mechanism. This mechanism also had to be decorated to demonstrate a design intent.
I chose to create a box that could be manipulated with two spur gears to move a series of heart gears. These gears would move letters up and down to spell something of my choice. I spent a while trying to decide whose name would get the honor of being spelled by my midterm project, but upon reflection I felt one of my little sisters would appreciate it most. Here is one of my first drawings of the machine:

My first move was to create my 2d designs. Here are the various components of my design in 2d:

My boxes, with various holes for the letters to move through

My heart cogs, which press the letters up and down, and my stoppers, to hold the various cogs onto their dowels:

My spur gears. I could not find a free source online to create these, so I ended up using a youtube tutorial to create the gears from scratch:

The letters of my sister’s name, not sure why I don’t have them in their proper order. Her name is Anja. There were various issues with the font of the letters as well as the fact that an ordinary “A” would have a hole that would fall entirely out when cut. I was able to fix this after much agonizing by making the text boxes on illustrator into paths:

I cut everything out of cardboard and was happy to find that all was as planned:

The only issue I saw, which I was able to rectify in my 2d design, was that the holes in the top and bottom boxes were not lined up:

Next I cut the bottom box of acrylic and the top out of wood, as well as the spur gears of aluminum with the water jet cutter and the heart cogs of acrylic. Dr Wettergreen told me that my homemade gears were likely not going to work, so I downloaded new ones from gear generator.com and cut those. I also added a hole to one where I would put the user interface; a dowel as a handle. I also sandblasted them to make them look more uniform:

From here my next step was to plasma cut the letters. I started by doing letters that were cut through in steel, but didn’t like the look of them:

Instead redid them using plain circles out of aluminum, which were much more smooth and barely needed any post processing. I sandblasted them and spray painted them, then etched Anja’s name into them using the laser cutter:

At this point I started assembling everything. I noticed that the holes for the dowels were quite tight so I decided to start on the small dowels that would hold the letters, and used a belt sander to make the bottoms smoother over the heart cogs:

From here, I decided to put the dowels in the bottom box and try out the heart cogs. As it turned out, the heart cogs did not work. Every time I turned the hearts, the dowels became stuck sideways:

From here, I had a panicked moment and started on a new mechanical movement instead of the heart cogs. I printed out a new bottom box of wood to test my idea, as well as a small cog, but found that this idea did not work either as the shape of the new cog twisted the letters rather than pushing them up:

I decided to stop panicking and go back to my original idea, but this time with a second acrylic box on top instead of the wood box to stabilize the letters. this worked very well, and I was able to assemble everything:

This design worked extremely well so I left it to dry.Perhaps that was my mistake. In hindsight, this is the point at which I should have handed it in to Dr. Wettergreen and demanded an early grade. When I returned, one of the heart cogs was extremely off, to the point where my dowels were falling in between this cog and the next one and getting stuck. Of course, I had already glued everything together using acrylic glue. I tried to reopen it again to fix the cog and ended up giving myself a nasty gash which is actually pretty small now that I look at the picture but bled a good amount:

Things were not looking good. I determined to restart, and quickly cut out everything on the laser cutter. I did not want to water jet cut again, so I used a hammer to destroy version one to get the gears out. After I cut myself yet again getting the first one, I decided that the trash was the home for the second one and just used a laser cut version for the second gear. On the positive side, the acrylic gear ran much more smoothly than the two metal ones did. I felt that for version 2.0, I could improve. I decided to simplify my design a bit and only use 3 dowels so you could better see the letters as they moved. Thus, I removed the heart and chose to spell “Ana”, a family nickname for Anja instead. I also decided to use double stacked heart cogs so that I would not be in danger of losing another cog off the edge. I was able to put everything together, but in my haste, I did not manage to sand the bottoms of the dowels again. I DID, however, sand the external dowels, and got a fair amount of sawdust INSIDE the sealed box. For these reasons, version 2.0 overall turns much LESS smoothly than the first version, to my extreme frustration. At this point however, I had to make the decision that the ENGI 210 midterm was not the hill I wanted to die on, so I labeled the midterm with my name and turned it in:

All in all, I found this project quite frustrating. Nonetheless, I do really like the aesthetic of the box and learned a lot while making it. As I hoped, it reminds me a lot of the color factory in New York, which is a place Anja really was looking forward to visiting when we went to New York this summer.  I hoped to give this to my sister but given how grumpy it is, I am not sure if I will be. Perhaps I will make her something less temperamental later in this course. At any rate, here is the cost breakdown for the midterm:

Acrylic sheets: 2×13 – 26$ (Blick art supplies)

Thin aluminum sheet: 9$ (BuyMetal online store)

Thick aluminum sheet: 21$ (Lowe’s)

Spray paint: 4$ (amazon)

Dowels: 10$ (Michael’s)

Machine shop and tools: 50$ (txrx makerspace lab in houston)

My time: ~15 hours, 10$/hour: 150$

Total: 270$