Apparently its technically octopuses because octopus has a Greek root but either are acceptable in most contexts. Anyways, after seeing multiple 3-D printed squids and octopuses throughout the OEDK, I realized that I wanted to 3-D print an octopus that could articulate. On thingiverse, I found an octopus model and I downloaded the STL file from this link:

Figure 1: Thingiverse Octopus Print

Printing Setup

I then I set up print of that STL on both the MK4 Prusa 3-D printer and the Bambu X1 3D printer. In an effort to maximize the amount of space the three print took up in the gumball, I printed the STL file at a variety of scales ranging from 50% up to 85%. I found that the print at 85% scale was able to fit snugly inside of the gumball.

Figure 2: Prusa and Bambu Print setups

Printing and Post Processing

While attempting to produce these prints there were a variety of print failures. While size was a factor for these failures, I think that the primary issue was first layer adhesion. To address this, I decided to print with brims for both the Prusa and Bambu prints. With these brims, prints were successful but required more post processing. After the prints were created, I completed post processing in the form of removing supports, and the brims that were on the 3-D printed piece. Removing the brims ensured that articulation was possible with the prints. I also did a little wet sanding on the prints with 400P sand paper.

   

Figure 3: Print Failures

 

Figure 4: Prints with brims

Figure 5: Post-processed prints

 

Finally, I placed my prints into the 5 gumballs as well as printing out a sheet with the thingiverse links and cut the page into slivers that could fit into the gumball.

Figure 6: Completed project

Figure 7: Clean workspace

Figure 8: Clean Workspace

Conclusion

Overall I am satisfied with my final prints. There were a lot of unexpected print failures and learning experiences along the way but I feel that this project has helped me grow more comfortable with FDM printing. There were imperfections that stemmed from not being able to fully remove the brims on the Prusa prints which was unideal. If I were to complete this project again I would have chosen a print that had more surface contact with the build plate since that was the main source of print failures in my experience.

Cost Analysis

The total cost of this project was calculated to be $211.93. The vast majority of the cost was due to the cost of labor. I spent multiple hours resetting and modifying prints to improve adhesion. With all the practice and experience I’ve gained from this project, I believe I could rapidly iterate in as fast as half the time, decreasing costs by nearly 50%.

 

Type	Item	Price	Source	Quantity	Total
Materials	PLA Filament	$0.43/ounce	amazon.com	~7 ounces	$3.01
	Gumball Capsule	$0.45/capsule	amazon.com	5 capsules	$2.25
Labor	3D printer operator	$19/ hour	ziprecruiter	5 hours	$195
Overhead	3D printer overhead	$1.33/ day	makerbarn	5 days	$6.67
Total					$211.93