introduction
This project took me longer than I expected because the first piece I chose wasn’t impossible sadly… Ghosty Boy was my original print and I had assumed that he was impossible due to the shape of his body but unfortunately I did realize that he could have been made by molding… I had planned to make a spoopy (yes, spoopy) object in light of spoopy season but by the time I pivoted directions, Halloween had passed and so I decided to take a new route.
I watched Ratatouille recently and I decided to turn Ghosty Boy into Mousey Boy in honor of Remi, everyone’s favorite rat-chef. I was certain that my piece would be impossible enough because of the articulated joints that could be accomplished in a single print. The file I used from Thingiverse can be found here: https://www.thingiverse.com/thing:5268216
Printing
Before I dedicated time and materials to printing Mousey Boy, I had to decide on the right dimensions. Taking my experience from Ghosty Boy, I had printed him too small and wanted to maximize the space within the gum ball case. I took calipers and measured the gum ball to have a maximum width of 46 mm and a maximum height of approximately 50 mm. To give myself some clearance, I scaled Mousey Boy to a width of 40 mm. When slicing, I set the infill to 10% (based on creator’s settings) and the remaining settings were nominal (after discussing with an OEDK tech).
Another consideration before printing was what kind of bed adhesion (raft, skirt, and brim) I wanted to print with. I decided to print with a brim adhesion first and see how difficult it would be to remove it once the print was finished. I chose brim because it was thinner than a raft and would only be in the edges of the print instead of the entire shape.
I printed the demo Mousey Boy and it took approximately an 1.5 hours. I didn’t consider the length of his tale to be a problem because I thought I could fold it in to fit the case, but unfortunately he was a bit too big. The brim was easy to remove but would get stuck between the articulated joints, making the final product have some jagged ends to it. From this print, I decided the final dimensions would be 30 mm width and I would use a raft.
Post Processing
I printed 4 Mousey Boys with the FDM printers and 1 Mousey Boy with the SLA printer. The FDM prints only required me to remove the rafts in order to post process but the SLA print was more involved… or so I thought. When removing rafts from my prints, 2 of my Mousey Boys had their tails ripped off. The rafts were definitely easier to remove altogether compared to the brim from my demo print, but the rafts were thicker and required more strength to detach. The tails were thin and so I had to be delicate around that area when removing the raft– 2 casualties out of 4 was still a win honestly. For the tails that broke, I used hot glue to attach them together and although they don’t articulate like the functioning tails, they still held on and maintained their aesthetics. 
After printing in SLA, I had to remove the supports, wash the print in isopropyl alcohol to remove the resin, and finally cure it. One of my Mousey Boys had its tail completely ripped off and so I had to re-print it (this Mousey Boy will come in handy later). The second print came out successfully, but the tail was stiff and unable to articulate at all. SLA printers don’t do well with moving parts and this was definitely observed in my SLA print. The articulated joints weren’t able to move at all and therefore could not fit into my gum ball case. 
I decided to use the Mousey Boy that had its tail severed as it was able to fit into the case. Even though my prints had some bump in the road, I was still proud of all the Mouse Boys I produced!
Cost Analysis
Materials
Failed Prints: $0.12 (Ghosty Boy) + $0.36 (Mousey Boy Demo) + $0.75 (SLA Mousey Boy w/o tail) = $1.23
Final Prints: $0.84 (4 FDM Mousey Boys) + $0.75 (1 SLA Mousey Boy) = $1.59
Labor
Labor: 5 hrs @$7.25/hr = $36.25
Overhead: 1 hr @$15/hr = $15.00
Total = $54.07
