Introduction
We were tasked with creating an “impossible object” to 3D print using two different techniques of printing. This was a single person project, so I was on my own for this one. I knew that with the limited 3D printers in the OEDK, there would be a rush for spots, so even before the assignment was assigned, I started getting my prints off in hopes of being done before the big rush.
First Step: Finding A File (First Attempt)
The first thing to do to create my impossible object was to actually find the object I wanted to print. After scoured the site for awhile, I found a cute elephant whose legs and head moved up and down and had a flexible trunk. I immediately found that I loved the concept, and so hit that download button and exported the stl file to the OEDK slicing computer on an SD card.
Second Step: Scaling the File (First Attempt)
On the OEDK computer, I needed to scale and slice the stl file. We had to scale the elephant because part of the assignment criteria was to fit each piece into a little gumball machine toy holder. I measured the toy holder using a caliper and then scaled the elephant to the correct size (about 1.6×1.6 inches). Once this was complete, then I sent the file on to a MicroSD card and ran to the printer.
Third Step: 3D Printing – FDM (First Attempt)
At the printer, I inserted the SD card and hit print. 40 minutes later my print was done, but the bottom had failed, so I went back to the computer, edited my file to have a raft as well as added two more elephants to meet the project requirements and printed them. This time, two hours later, there were three elephants who were perfect, so I started to move onto the other method of printing.
Fourth Step: 3D Printing – SLA (First Attempt)
I created another file for the Form Labs printers and sent that file to the printers. This is where the oopsie of the project occurred. When I pulled the print out when it had finished, I washed it and cured it, but when I tried to move the legs and the head, I found that the resin had fused to each other. This was not good and after consulting Danny, we determined that the print was too small for the Form Labs printer to not have fusing of the material. With a heavy heart, I had to do the process again.
Fifth Step: Finding A File (Second Attempt)
Once again, I was scouring Thingiverse. This time, I looked up “impossible” and lo and behold, an impossible object appeared: a cube with a sphere loose inside of it. This was beautiful to me and would work for both printers, so I sent the file (again) to the OEDK printer.
Sixth Step: Scaling the File (Second Attempt)
At the computer, I had save my measurements of the container from last time, so I scaled the object, made two more copies of the scaled object and put it on another SD card and took it to the printer.
Seventh Step: 3D Printing – FDM (Second Attempt)
Once again, I inserted the SD card into the printer, praying that it would work this time. And thankfully, it did! I forgot to do custom supports so it took almost an hour to remove them all, oops. But, with these done, I was confident that the SLA prints would come out clean, as long as I did custom supports.
Eighth Step: 3D Printing – SLA (Second Attempt)
Moving to the OEDK computer for hopefully the last time, I opened up the Form Labs software, ran my file through, added some custom supports to make the design greater supported and set it to print. Little did I know that people would be very slow in rotating their prints, making my cubes print out over a day later than what they should have. I waited for 5 days till I finally found out that just directly sending the prints to the printer instead of queuing allows for an instant print. Once I found out about this, I printed my object, washed it, cured it and I had five cubes with balls in them, an impossible object, to show for my effort!
Reflection
Honestly, it was really nice to have a more manageable project right after the midterm, it was like a breath of fresh air. 3D printing is also one of my favorite things to do and is so interesting to me, so that helped too. Changing my design was tough because it set me behind to printing with everyone else and not missing the rush, but I got through it. At the end of the day, I was proud of my work.
Cost Estimate
- 6 hours of work for $15/hour: $90
- PLA: $2.00 for prints and supports of 1, so $6 total
- Resin: About $2 for both cubes
Total Cost: $98
