The impossible object I decided to download from Thingiverse was made by ‘fluffy’ and consisted of interlocking, concentric rings that could be individually rotated. (https://www.thingiverse.com/thing:33945). Since this object contained components that were interlocked during the fabrication process, it constituted an object that would have been impossible to practically create in a single manufacturing process apart from 3D printing.

The two printing methods I used were FDM and SLA.

FDM:

FDM was performed by a PRUSA i3 mk3 printer and was not overly difficult. After downloading the object’s stl file from Thingiverse and uploading the file to 3dprinteros, I used the layout tool to determine the best position to print the object in.

Next, I sliced the file and used the OEDK’s default settings for its PRUSA PLA Printers. After a preparation time of around 2 hours and a printing time of 30 minutes, the impossible object was successfully printed as shown below.

SLA:

SLA was performed by a Formlabs Form 2 Printer. After downloading the stl file from Thingiverse, I used software for the Makerbot Replicator 2 to convert the file into a format fit for the printer’s sl1s file formatting software. When the file was uploaded to the sl1s-formatting software, I sliced the part according to the OEDK’s default settings as shown below.

Next, a usb drive was used to transport the object’s sl1s file to the SLA printer, where it was printed in about 2 hours. After washing the object, I had successfully printed the impossible object. The 2 hours it took to print the objects combined with about 2 hours spent prepping the object to be printed amounted to a total of 4 hours being spent for SLA.

The only issues concerning these prints is that some of the individual layers on the sides of some prints did not completely adhere to the overall print. However, it was easy to remove these unattached layers using a utility knife.

Cost:

The cost for the 10 grams of PLA material used was $0.26 while the 20 grams of SLA resin used amounted to $3.50 ($175 for 1 liter of Form 2 resin) for a total material cost of $3.76. Two hours and 30 minutes of time needed for the PLA print combined with the 4 hours needed for the SLA prints yields a total time of 6 hours and 30 minutes spent. Assuming a basic wage of $10 per hour, the labor costs for this project amounted to $65. Furthermore, since the OEDK and these printers are free for students to use, there were no membership fees or costs incurred by purchasing the 3D printers and the necessary software. Therefore, by combining the material and labor costs, it is determined that the overall cost for this project was $65.