This week I 3D scanned a clay hand-mold and 3D printed a Soundcloud waveform.

3D Scanning

I decided to 3D scan a piece of clay that I had squeezed into an ergonomic grip. The idea was inspired by a project I did a few years ago to make an ergonomic bag handle. (see here and images below). Back in the day I didn't have access to a 3D scanner so I used some approximation of the serial sections scanning approach in which I cut the clay piece into a few pieces and just took calipers to it. Now, though, I can just hit "scan" and see the physical atoms quickly turn into bits of information.

I struggled at first to get the Minolta to talk to geomagic. Every time I hit Plugin-Minolta... I gave me an error like "Failed to load Minolta V910." I restarted both the computer and the scanner. Still, no luck. So... I started playing with the Next Engine.

I think my clay hand-mold is pretty much the ideal model for the Next-Engine scanner. Everything went very smoothly and it produced a really nice 3D model.

Back to the Minolta... I restarted the computer again with the scanner on, let it sit for a little bit, and it magically started working as it should.

The Minolta also went pretty smoothly. I scanned the object at 8 different orientations (each 45 degrees apart). The object was not perfectly centered on the turntable so the scan looked quite rough initially:

After I merged the points, it looked a lot better...

Cleaning it and filling holes produced a nice and relatively smooth model. My only complaint is the gross color that it seemed to prefer to the bright yellow. I think next time I'll try scanning with a little more light.

It's interesting to look at the differences between the output of the two scanners. Viewing them as pure STL's better reveals the small surface differences:

Can you guess which one is which? (answer is below)

The one of the left seems a little smoother but otherwise they're very similar (note: I did slightly smooth the clay model in between scanning with the left and the right so that could account for some of the difference). Of course, both software packages let you clean and polish you model however much you want. For scanning something like this clay hand-mold both scanners are perfectly adequate. Answer: Next-engine is left, Minolta is right.

3D Printing

I would've liked to be able to 3D print the STL I created from 3D scanning but since I was away for the entire weekend I couldn't get my hands on the Minolta scanner in time. Instead, I decided to play around with tracing images in Solidworks to create an object with a audio waveform embedded in it.

Soundcloud makes nice waveform images that are easily downloadable as PNG's by digging through the HTML source. I, then, imported it into Solidworks as a sketch picture. Solidworks has a nice tracing feature but you need to activate the add-in for it to show up. You can do so by going to Tools->Add-ins... and selecting both checkboxes next to autotrace.

Once you trace the object it should create a nice sketch the traces the outline of the black regions.

I then extruded the sketch and started twisting and bending it...

The final step was to export the STL and scale it for the 3D printer. I scaled it down to roughly 4.5cm diameter. It's a little small to be practical for anything but it does look cool. Scaling it down to this size also poses an interesting resolution challenge for the 3D printer. I was curious to see how well the print would come out...

Here it is in its final (physical) form: