For this assignment I had to find an impossible object to print using both FDM and SLA printers. I decided upon a design that was a 3d version of  Sierpinski’s triangle. I found this design on thingiverse (LINK).

After finding my desired design I scaled it to what I though was the appropriate size however it was too big. These first prints I printed using a 10 layer raft. After realizing how big my print was I scaled it down to fit within the ball.  I started a test print to see how my new size would turn out however, with the smaller size and the raft the bottom of the pyramid would break and stick to the raft.

For the next print I then used a skirt instead of a raft and my prints came out fine. After this I then printed out 3 pyramids using the Prusa i3 printers with FLA filament.

After the FDM prints were done I got started on my SLA prints for this assignment. I set up the print on the computer for one of the formlab printers to print flat. This print came out under-supported and caused a part of my print to not print properly. After this I used the auto set up rotate and support my print in 1 click option and ended up with the same result, an under-supported print. After these two failed prints I then set up the print for the Prusa SL1S printer. Using this printer and keeping my print flat with the auto supports my first SLA print came out. After this I reprinted the same design and got all 5 of my pyramids.

Reflection:

I have had prior experience with both FDM and SLA printers however this was definitely a learning experience for me especially with the SLA prints. The FDM prints were fairly simplistic to me and I was able to understand how to set up and print on the prusa i3’s fairly quickly however knowing how to choose the proper supports so that the fine details of the print is preserved was definitely a little bit of a challenge. The SLA was harder in terms of supports as well. Because the SLA printer prints downwards many of the assumed support isn’t there and at the same time there are some supports that are now unnecessary from the same fact. I prefer using the SLA printer aesthetically because I cant see the layers however I believe the FDM to be more practical in terms of quick prototypes.

 

Costs:

Filament: 6 prints – $0.66

Machines:

Prusa i3 = 25/hr , 6.5hrs = 162.5

Prusa SL1S = 30/hr  2.5hrs = 75

Labor: 3.5hrs – (15/hr) = $52.5

Total: $290.66