3D printing: Shells and Infill (Part 3: Printing the 3D model hand)

Before we begin: In part 1 we described what are infills and shells. In Part 2 we did some testing.

We took what we learned from part 1 and part 2 and printed our 3D hand model! For your information, the 'original' model had 15% infill and 2 extra shells. The 'new' model was set to 0% infill and 1 extra shell. Lets look at the results.

The Main Hand Body
Original: 224 grams (24 hours), material: Red PLA
New: 54 grams (6 hours), material: Red PLA
Comments: The New model was four times lighter, more aesthetic and it took significantly less time to print! The improvement in weight was due to no infills. It looked better since we printed the new model standing (as shown in the pictures) but the original model was printed lying flat at the back of the hand with the palm facing upwards. It took only 6 hours to complete compare to 24 hours because less material was used.

New and Original hand body (Palm side)

New and Original Hand Body (Back of Hand)

The Fingers

Original fingers : 118 grams (13 hours), material: Red PLA
New fingers : 128 grams (13 hours), material: transparent PLA

Comments: The weight had increased and it took around the same time as before.  Furthermore, it looks really ugly. Each individual piece did not have a uniform material density. The bottom half of the printouts were solid (even though we set it to zero infill) and the top half had no infill. You can see in the image (bottom right) that the base is very yellow because transparent PLA turns yellow when it is densely printed, hence solid! The top part is slightly transparent because less material was used. We will probably have to print out another batch!

New fingers and Old fingers

Base was solid while the top has no infill

Conclusion: The body of the hand improved in weight however the fingers did not. Something went wrong and we will investigate further.