I created a new version of my prototyping keyboard. I did a better job designing the case this time. It's much more sturdy and doesn't have nearly the amount of flex that my last attempt had. I'm still trying to decide on a final layout I want to use for my next keyboard build. This is pretty close to what I'm thinking. But I can't do the curved thumb cluster that I want with this.
Here's an exploded view of how the case fits together. The 5.6mm switch pieces are much more sturdy than before. I left one side of each of the two 3mm layers below this with the idea of being able to run the wires out through there. But depending on your layout, it can be hard to bend them through. So I used some of the extra 3mm pieces I was planing on using just to leave enough spacing under to create the path for the wires out the back. The open ends on the middle parts are a weak point and one broke already. So I'll be closing those up. I have holes in the four corners to hold it all together. Plus ones along two sides to help separate the wires by columns or rows and hold them in place.
Here I have my switch plates all arranged and held in place with two of the cross supports off to the side.
And here is the bottom with everything put together.
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