Be very sure you want to make THIS keyboard.

Still here? Okay let's do this.

Or use mine,

or redesign mine:

https://github.com/trisimix/janck

Here's some tips: don't use fritzing if you are going to print using seeed (a pcb printing service). As of 2018-11-04 fritzings gerber exports don't work with their service.

I ended up using easyeda, it even has a web interface if you're lazy. Or a linux client if you're not.

I designed one 100mm x 100mm pcb, you connect up to 3 of them by the dots on the sides, and the rows. This way you can save money and prevent extra pcbs since most places have a minimum pcb amount.

I missed two connections on my original design below. Oops. Didn't matter.

1n1448 is what I used.

Solder and clip them, try to keep the side the keys will go on flush.

I used mod-m linear switches.

The pcb I designed uses  teensy 2.0 ++

Heres the pins I chose to use.

I forgot to take a picture, but theres another board, this time with all 25 switch spots fitted. I chose to do one more, for a total of 47 keys (a weird ass 40%)

Take some of the pins you snipped off from the diodes, or snip some more off perfectly good electronics if you're lazy. Or buy something real to do it. connect the boards together using there pins.