We started the LipSync housing design using ABS filament. ABS was chosen for it's strength and temperature threshold. PLA can warp in hot environments, such as the inside of a vehicle on a hot day; therefore it was avoided. Here is one of our original ABS designs:

One issue we came across is each 3D printer model and slicing software package prints geometry at slightly different sizes, especially internal diameters. We approached this nuance by creating a hole template which we printed with our available printers and software packages:

We measured the printed holes with a caliper and compared them to the nominal sizes. As you can see in the graph below, the relationship between the nominal diameter and the printed diameter is linear. This allowed us to derive simple equations to size holes accordingly and create a tolerance among different printers.

Because the LipSync will be used in hospitals, we wanted to create a housing design which would block harmful electromagnetic interference (EMI) signals. We explored materials and came across a new filament on the market, conductive graphene. The print quality was superb and the conductivity was very high; exactly what we wanted to create a Faraday cage around the LipSync electronics:

Unfortunately, the filament was very expensive and it jammed the 3D printer extruder on multiple occasions; not open-source friendly. We explored other options and came across conductive ABS. The print quality was almost as good, it was easy to use, and the price was right; we found a winner:

The conductivity was substantially less than conductive graphene, at 300K Ohms across the rear housing; however, this seems to be enough to see the results we're looking for. We'll know more after a professional EMI test.

We designed the housing to be elegant, streamlined, functional, and fun to build. With complex geometry, threading, and an integrated mounting point, the LipSync housing should meet many of your 3D printing desires. Enjoy!