At first, I decided to print a ball in a cube, as shown in Figure 1. I chose this because I thought it would be fun to play with even within the size of the capsule we were given.

Figure 1. Ball in Cube Design from JohnMcN

First, I downloaded the .stl file and opened it in 3DPrinterOS. I chose to scale it down to 50% of the original volume so it had a length of 16 mm. Then, I used the software to send the file to the Formlab printer and begin the project. After it was done printing, I soaked the design in isopropyl alcohol bath for 20 minutes then let it cure in UV light for another 10 minutes. To my surprise, I had no problems with this process as it printed very well and the supports were very easy to remove. The design before and after removing the supports is shown below in Figure 2.

 

Figure 2. Design before (left) and after (right) removing supports

Next, I moved on to the Prusa printers. I went through the same process of scaling it down, slicing it and sending it to the printer. However, I encountered many more mistakes this time. Some of my initial products are shown below.

 

Figure 3. Attempts of Printing Box in Cube on Prusa Printer

First, I tried to print several products at once (pink, top left), but one of them messed up and ruined all the others, so I decided to focus on printing one at a time (green, top right). After this also did not work, I decided to try to print it bigger so the walls would be larger and more sturdy/defined (blue, bottom left). This print finished, unlike the previous, but the supports were connected too strongly to the ball and were impossible to remove without damaging the product. Through all of these trials, I ended up with one okay product (black in bottom right) and decided to use that one but move onto another design.

For my next design I chose a simple knot. While not as exciting as a ball in a cube, I had to chose a simpler design to fit within my time limits. This design is show in figure 4.

Figure 4. 3 Knot from eduardoviruena

This design printed much easier, within my first try. The supports were difficult to remove, but not impossible and I developed a technique as I did it more and more. I did print these very small which helped with my time constraint but I think they would have been cooler if they were bigger. However, I was happy that I finally got something that looked how I intended. The 3D printed products are shown below.

 

Figure 5. Printed Knot Design before (top) and after (bottom) removing supports

Overall, I ended up with 2 Ball in Cube prints and 3 Knot Design prints. They are all show in Figure 6.

Figure 6. Final Prints

In my cost analysis, I am assuming that the printer is available free of cost as it is to me at the OEDK.  The raw materials for these parts cost $0.30 for each ball in cube print and $0.05 for every knot print, 2X0.3 + 3×0.5 = $2.10. To produce these 5 parts (ignoring my previous attempts) it took 2 hours to print and remove the supports of the knot design pieces and 2 hours to print and remove the supports of the ball in cube design. Working at $12 per hour labor costs equals 4X$12 = $48.

Total cost of products equals cost of raw materials plus labor time = $2.10 + $48 = $50.10.