Hi everyone!

This week, we learned how to perform 3D printing. We were tasked to use 2 different printers to produce “impossible” objects and to ensure that their size would fit into gumball capsules. 

My Impossible Object

Impossible objects are defined to be objects that cannot be produced with conventional physical methods. Due to its versatility, 3D printing can produce “impossible” objects that have unique geometries. 

I chose to print the Mobius Bangle by “Creative_Hacker” on Thingiverse. I used the Bambu Lab X1 Carbon and Prusa i3 MK3 3D printers to create my objects.  

Sizing

To ensure that the object would maximize the volume within a gumball capsule, I printed 3 scaled objects. The diameter of the gumball capsule was around 2 in, or 50.8 mm, so I scaled the objects accordingly: one around 50.8 mm, one a little above 50.8 mm, and one a little below 50.8 mm. These were the dimensions that produced my prints:     

X	Y	Z
51.41 mm	50.6 mm	11.25 mm

All of my 3D printed used supports. However, the slicing softwares for Bambu and Prusa printers are different. Both softwares offer rectangular shaped supports, but the Bambu also offers tree supports. The tree supports are curved supports, which I felt fit my impossible object more. 

Post Processing and A Slight Mishap

After completion of all of my prints, I cleaned them up by removing all of the supports with pliers and wire cutters. I also wet sanded them too to give a nice, smooth feel. The tree supports on the Bambu were much easier to remove than the rectangular supports on the Prusa.

Then, I tested the fit in the gumball and realized that I accidentally chose the incorrect dimensions when I was starting the prints. I had the wrong picture from my camera roll pulled up when inputting the numbers. The correct dimensions should have been:

X	Y	Z
45.7 mm	44.98 mm	10 mm

 To fix this error, I wet sanded a bit more on the sides to ensure that the incorrect prints fit into the gumball.

If I did this homework assignment again, I would have reprinted with the correct dimensions.  After cleaning up my mishap, the corrected 3D prints were then placed in the gumballs with a slip of paper giving credits to the creator of Thingiverse. Overall, 3D printing objects is an easy process to complete that can help engineers create a diverse set of parts and devices… just make sure you print with the right dimensions! 

Cost Estimate

Item	Cost
3D Printing Designer Labor Cost ($29/hr) for about 2 hours	$58
Cost of the Prints (1 costs $0.34 according to Prusa Slicer)	$1.7
Total Cost	$59.7