How To Make (Almost) Anything Neil Gershenfeld

MCKENZIE ROSS HUMANN

MIT Department of Urban Studies and Planning

3D PRINTING AND SCANNING

10.05.22

group assignment:
- test the design rules for your 3D printer(s)
individual assignment:
- design and 3D print an object (small, few cm³, limited by printer time)
that could not be made subtractively
- 3D scan an object (and optionally print it)

Group Assignment

One of my classmates printed the design tests to determine the limits of the 3D printer in the arch lab. For the overhang test, the filament started to detach for the 6mm long right angle overhang. The angle test showed that the printer performed well up to the 90 degree overhang. Finally, the printer performed well for all bridge lengths.

3D Scanning

I tried scanning using two different methods. First, I scanned an object I found in the arch lab using the Revopoint Pop 2 Scanner. The object was a little shiny and was entirely made up of curved surfaces, so I suspected this would be difficult to scan. This hypothesis proved correct. The first attempt did ok, but lost a lot of the detail of the object's shape. I tried to scan a second time and this time the scanner had a difficult time tracking the object. The resulting scan looks very cool, but nothing like the real object.

I also scanned a candle holder I had at home using the Scaniverse app on my iPad. This worked better than I expected, but the quality was really dependent on the lighting.

Interesting metal object I found by Jen's desk

Scanning attempt 1 in progress.

Scanning attempt 1 results.

Results of second attempt.

Scan of candle holder using Scaniverse. This side had the most light and scanned the best.

This side had less light and did not scan as well.

The inside parts of the candle holder also did not scan well.

3D Printing

I designed and 3D printed a gyroscope this week. While a gyroscope could be designed to be assembled after manufacturing and therefore would not necessarily require additive manufacturing, I designed this gyroscope to be printed all in one pass using Fusion 360. Based on sound advice from one of the TAs, I first printed some smaller pieces to test different joint sizes to avoid the pieces from being fused together. I printed three different pieces each with a different pin size. Indeed, the smallest pin size was the only one that cleanly separated from the surrounding hole. After these tests I modified my design to incorporate the smaller pin-size (thank goodness for parametric design) and also extended the pin length to prevent any of the inner circles from falling out easily. The print came out pretty well for a first pass, however I could have further extended the length of the pin.

My gyroscope design in Fusion 360.

Using the joint functions, I could model how my design would move.

Here I tested three subsections to figure out the right joint size settings.

The joint with the greatest space between the pin and the hole easily separated.

My new (fake) gyroscope.

The gyroscope easily moved into this position, however there was some friction still at joints that did not separate cleanly. Since the middle section is rather light there won't be enough momentum to overcome the friction in the joints to create lasting movement.

The joint pins were still too short and dislodged a little too easily.