Möbius Band

• Ricky Gonzalez

Step 1: Choose a design

The first part of my 3D printing assignment was to determine an impossible object to print from the Thingiverse. I settled on this inner-linked Mobius band that would be impossible to make without using a 3D printing technique.

Step 2: Determine appropriate 3d print settings

Once I decided on my impossible object, I downloaded the file and used the 3DPrinterOS software to customize the settings for my object to be printed using the FDM printers. First, I scaled my object to be ~35 mm x ~33 x 6mm. Secondly, I keep the default slice settings to o.25 mm layer height, 1 mm wall thickness, and 15% infill density. I also added a raft to my print and unchecked the “Generate Support” box as I believed that supports weren’t necessary for my object. Finally, I sliced the object and proceeded to print it. Although most of the print came out alright, there were noticeable extrusion defects in the spots that had overhang and required supports.

For my second print job, I decided to use the same exact settings as the first but kept the “Generate Support” box checked. Unfortunately, with the 3DPrinterOS, one cannot alter the automatic supports where the software believes is necessary. As a result, it added support between the links, making it almost impossible (pun intended) to take off.

For my third print job, I increased the scale of my object to ~40mm x ~38mm x 7mm. Additionally, I decided to change the slice settings to 0.1 mm layer height and 0.8 wall thickness but kept a 15% infill density. For this print, I did not generate supports because I believed with the smaller layer height and wall thickness, the extrusion defects from the first print job would be corrected. Although the third print looked much better, it still had some extrusion defects in the spots that had overhang and required support.

For my fourth print job, I decided to take a different approach. Instead of using the 3DPrinterOS, I used the PrusaSlicer software, which allowed me the option to generate support only on the build plate. Additionally, I increased the scale of my object to ~45mm x ~43mm x 8mm, changed the slice settings to 0.1 mm layer height, 0.8 wall thickness, and kept a 15% infill density. The result was exactly what I wanted! The supports were only generated on overhangs rather than in between the links. As a result, the supports were easy to take off and I ended up with a nice print!

For my fifth and final print, I used the PrusaSlicer software to 3D print using the SLA printer. Since the settings for the SLA printer are good by default including the supports, all I did was change the scale of my object! And after nearly 5 hours, I had a nice 3D-printed object! I proceeded to take it out of the SLA printer, cure it, and wash it. Lastly, I took off all the supports and used isopropyl alcohol to clean off any sticky residue left behind.

REFLECTION

Overall, I liked this project, but it proved to be more tedious and challenging than I initially anticipated — especially, in determining the appropriate setting for one’s print. I used a very heavy test-and-verify approach, which took lots of time and failed prints. Nevertheless, I found the appropriate settings and took off with them! I am very pleased with both my final FDM and SLA print, but if I had to choose one, I would pick the SLA print. The reason is, it has a much cleaner look, where layers are not as visible as in the FDM print.

Cost estimate

 

Print Friendly, PDF & Email