After our sassy owl midterm was over, it was time to move into the 3D realm of prototyping, and what better way to start than with 3d printing!

Follow my journey to recreate your own mini 3D prints 🙂

Step 1: Thingiverse Scavenger Hunt

The assignment was to print an impossible object meaning the object has either interlocking and moving parts or intricate geometry that can only be manufactured using a 3D printer. I started by looking for objects with complex geometry on thingiverse.com and found a stereographic projection which is a map from a sphere to a plane. I thought it was a cool concept so I decided to go with it.

 

 

Step 2: Attempt to Print it 

Using the 3DprinterOS software, I uploaded the file, centered it, sliced it, and printed one at the original scale, so I knew how much to scale it down to fit into the gumball capsule. The original was at 80 mm but had a lot of supports that needed to be removed. The supports were really hard to remove, so I decided to print a scaled-down version at 40mm without any supports, lower the layer height (0.08mm), and lower the wall thickness (0.8mm). However, that did not work very well, and some of the edges were not sturdy enough. I printed it again with an even lower layer height (0.01mm) and the same wall thickness. However, this time the print failed completely. I tried again with a scaled-down version while keeping the supports, but when attempting to remove the supports broke the piece itself. It was a very disappointing moment.

Step 3: Back to Thingiverse scavenger hunt 

I went back to thingiverse.com and looked for other objects that did not require much support. I went with an articulated excavator. The excavator was actually inside a kinder egg, but I only chose to leave the egg behind for this project.

 

 

 

 

 

 

 

Step 4: Back to the Printer

I scaled down the executor to 40mm for the FDM Prusa Printer, and it took about 33 minutes to print. However, it ended up being way too small for the hinges to work, and every time the supports were taken out, the object kept breaking. So, I scaled the print up to 70mm, and while that took longer (1 hour 47 minutes), it was the perfect size. I had to be careful to remove the supports (learning from my mistakes), so I don’t break the object. I was successful in removing it and the hinges worked perfectly! I printed 3 more of the same objects on the Prusa printer and they turned out beautifully and fit perfectly in the gumball capsule.

 

 

Step 5: Jump Print Hurdle #2

Hurdle Number 2: Print an SLA print, wash, and cure. To print the SLA print, I used the FormLabs printers. The prints from 3DprintOs were downloaded and queued up to the SLA printer. I kept the same scale which was a mistake. The print took about 9 hours because there were many supports that needed to generate, and that might have been because it was accidentally rotated. After a long 9-hour nap, I put the print in the washer and then to cure it. The washer takes about 15 minutes and the curator takes about 25 minutes. There were a lot of supports to take off, and it took a while. The print did not look as clean, maybe because of the residue from the supports. Also, because of the resin, the hinges were not working and therefore could not fit in the gumball capsule. Sad. So, it was time to go back to the printer. I scaled it down to 30mm, printed it so the flat side was on the surface. This way there were no supports, and the print only took about 40 minutes. After it was printed, the object was washed and cured, and tah dah, it was all ready. Even though it was not functional, it was very cute.

 

 

 

 

 

 

 

I put all of them in the gumball capsules, and could not help but ask myself, should I sell these to McDonald’s to be a part of their happy meals?

This was definitely a learning experience. Just like all the other assignments, you’d think everything is going to go smoothly but there will be a lot of troubleshooting. If I had more time, I would have figured out how to print the stereographic projection at a smaller scale without supports. However, I decided it would be best to pivot away from that for the sake of this assignment. I did take off the supports from the actual regular projection (took a lot of effort), but it turned out really nice (picture below). There is a lot that goes into 3D printing such as knowing the right temperature to print at, the correct layer height, and wall height. All of this requires some experimentation and a lot of practice!

Step 6: Calculate Costs 

Material Costs(excavator): 
Prusa Prints : $0.07 + $0.22 (x4) = $0.95
Resin Prints : 0.023kg @ $24.99/kg = $0.57
Labor Costs:
8 hours * $7.25 = $58
Total = $59.52