Modifications:KBC Poker X:Pure Center Support Modification
The standoff in a Pure case will collide one of the pads for D51, which serves the "G" key switch. In order to make use of this stand off, the diode and associated pads and traces need to be removed. I opted to remove both pads and their traces to ensure that the entire surface was flat. At a minimum, the trace needs to be cut near the switch solder pad and the via at the other end of the trace.
I used a pair of calipers to locate the position of the hole. Horizontally, it aligns perfectly with the old trace. Vertically, it aligns just below the center line of the two positioning holes for the "H" and "G" switches. You can see the score mark in the above picture. A 3/32" drill bit was used.
A new diode needs to be put in place of D51. I just used a standard 1N4148 type, which are cheap and available anywhere. Any small signal diode will do. The cathode (side with the strip) needs to be soldered to the "G" switch pad and the anode to that row of the matrix. A handy place to pickup that row is on the anode of the "H" key diode, D52. Don't use the "F" key's diode. It's on a different row. I used some Teflon tubing to protect the leads.
This PCB was part of the Geekhack Poker DIY Kit, which had an aluminum case as an option. That case turned out to be for the Pure, which is what prompted this version of the mod. It is wise to use some sort of padding between the PCB and metal cases such as this to prevent possible shorts. The metal ribs can and will rub through the solder mask. Some people use a thin foam pad. I just used strips of electrical tape.