For our 3D printing project, we were tasked with printing an “impossible object”! I was very excited about this assignment because I love 3D printing and have experience with it from my internship and past/other classes. I first started off by going to Thingiverse to find my object. I wanted to do something with an articulating joint or hinge! I came across the Infinity Cube by mjdargen and decided to print that as my impossible object.

I downloaded the f3d file and opened it in Fusion 360 to check the dimensions and scale appropriately so that my object would fit inside of the gumball capsule. I first scaled it by 0.5 because I wanted something small and cute! Below you can see how they turned out using the FFF printer. The printer was able to successfully print it but some of the cubes got stuck together and many of the joints broke off. I tried 3 times before I decided that printing at that small of a scale wasn’t viable.

Next, I scaled it by 0.8 instead and they printed perfectly! Once I was able to print 3 of them with FFF, I moved onto printing 2 of them with a resin printer. All 5 of my objects can be seen below. For all my prints I used the OEDK’s default settings and did not have to change anything in order to print them.

As you can see below, the resin printer was not able to allow for the cube and hinges to be separate. This happened because in between each layer of resin, it is cured. Meaning that each layer is cured to each other and not allowing the cubes to be separated by empty space. This taught me that not everything can be printed on all types of 3D printers. A very valuable lesson!

Overall, I loved this project! Even though this wasn’t my first time using a 3D printer I still learned a lot because I’ve never printed an impossible object before. Now I have a new perspective on really examining parts I want printed and figuring out which printer would be best to create it.

Cost Estimate
(3) 0.5 scaled PLA prints=$0.45
(3) 0.8 scaled PLA prints=$1.35
(2) resin prints=$2.50
3D printer rental time:$12/hr=$150
Labor (prepping files & 3D Printer OS):$12/hr=$6
TOTAL: $160.30

I felt that I was pretty efficient and quick to prepare the Fusion 360 files and set up the print so my labor cost was pretty low. Most of my cost comes from my objects printing. Each of the 0.8 scaled objects was about 2.5 hours. Since I sent multiple prints and various sizes, the number of hours was pretty high. Now that I know that printing at too small of a scale isn’t feasible, especially an object that needs to move around joints/hinges, I would be more aware of that and print at a more appropriate scale in the future. This would allow me to drastically reduce the number of hours I rent the 3D printer. In addition, I would also add multiple prints on one bed, if space allows, so that it’s operationally efficient.