Alps switch plate from 1.2mm PCB
Made some plates out of 1.2mm PCB material at EasyEDA.com. They work fine. When they list the thickness at 1.2mm it includes the copper and silkscreen layers. Without copper layers it is thinner than 1.2mm. These measure 1.16mm. The specs for Matias switches says 1.0-1.2mm thick for the plate so this works out well.
At 1.2mm it is quite flexible. The fiberglass material is very tough. I also added a lot of supports. With or without a PCB it is very rigid once screwed to the base plate.
I had intended to handwire this, but EasyEDA lowered their prices a lot, so I made a PCB for it instead. When I ordered the plates I got an error email from EasyEDA. I had made the layout with no copper layers at all. They questioned this. I told them it was what I intended and they proceeded. On the Gherkin PCB the screw holes are plated through with copper rings on both sides. This PCB has plain drill holes instead of PTH. I think, that since there were no copper layers it was treated as a single sided PCB design as there is soldermask on only one side of the PCB. This is actually good for me since I only have to sand off one side to get a nice bare PCB for dyeing.
The plates are not compatible with the OLKB Planck PCB. The switch spacing it not the same, the mounting holes also won't work with the Planck PCB.