The Zatarra Mark II - A Geometric 60% Keyboard Case (Modified Tray or Ring Gasket Mount) by BeagleChristo

Last crawled date: 3 years, 4 months ago

NOTE FOR PRINTING: I would recommend printing this model upright, which will eliminate pixelation along the curves.
BACKGROUND:
After experimenting with various modifications to the standard tray mount configuration in connection with the Zatarra Mark I, I ultimately settled on the instant configuration: 2.5 mm squares in the corners of the tray and isosceles triangles (base angle = 30 degrees, to avoid the need to use supports) at the top-center and bottom-center of the tray.
This configuration will allow for either a tray mount or ring gasket mount (using the technique described by HugoKeys in this video: https://www.youtube.com/watch?v=eP4Cz-8rdz4&t=1s&ab_channel=HugoKeys)
Even as a tray mount, I submit that the instant configuration is superior to ...

... the ledge mount, which created a harsh bottom-out all along the perimeter of the tray. By contrast, under the instant configuration, there are only six posts contacting the PCB.


... the standard standoff configuration, because there are no standoffs in the center of the board. Further, under the instant configuration, each standoff rests only under one key, whereas in a standard configuration, the standoffs sometimes straddle two different keys. Also, if you (1) split this case in two for printing (as I did, because my built plate could not accommodate the entire case) and (2) print each side upright (to avoid pixelation along the incline), the instant configuration will not require any supports, whereas the standard standoff configuration will require supports under the same printing conditions.

... the four-corner mount, which omits the two isosceles triangles. The four-corner mount (which I did not include in the Zatarra Mark I post) created an alarming amount of flex in the PCB and plate while typing. The instant configuration is considerably more stable, while still allowing for flex.
Finally, the instant configuration makes it much easier to place sound-dampening material on the bottom of the tray, because you don't need to cut around standoffs in the middle of the tray.
Update Aug. 29, 2020: added remarks about printing upright and sound-dampening material.
Update Sept. 7, 2020: added remarks about ring gasket mount.