I was having issues with my ‘o’ and ‘y’ keys chattering quite a bit, so I tried the typically suggested cleaning a few times. The cleaning steps were a good temporary solution but weren’t lasting long term, so I decided to just replace the two keys in question. I’ve thought about doing this before, but I couldn’t find the Matias Quiet Click switches anywhere that would ship CONUS until recently. If you’re in the same boat, I was able to find them here (priced well, in my opinion, and fast, free shipping).
Once I got the new switches, I thought replacing them would be a breeze (a bachelor’s in electrical and computer engineering has to be worth something). Despite my fairly extensive soldering experience, I messed up removing the two switches that I needed to replace and made a bit of a mess out of the back of the circuit board. I’d highly recommend using a decent quality soldering iron and solder wick/pump - I’d blame my cheap equipment for ~50% of my initial soldering woes.
I’d managed to 1) tear out the through holes when removing my switches because I didn’t remove enough solder to start with and pulled too hard on the switches, and 2) rip off the test pads for COL10 and COL13, which I’d end up needing to tie diodes into. Be careful when soldering/desoldering anything on those column pads.
After checking in with Jesse (firstname.lastname@example.org), a super quick response set me on the right path. The left-hand lead of the switch (when looking at the bottom, labeled side of the PCB) can just be tied into the row for that switch, so just bridge it to any other left-hand lead for a switch in the same row. The right-hand lead on the switch needs to be connected to a 1N4148 Switching Diode, which is then connected to the respective column. The cathode (side of the diode with the line/band around it) needs to be towards the switch, with the anode side connecting to the column.
The row connection was easy to make with a bit of spare wire, but the columns gave me more trouble. I was able to expose traces for COL10 and COL13 by scraping off some of the protective covering on the PCB, thanks to some documentation from Jesse (shown below).
arrow points to the area the COL10 trace pops through to the back/bottom of the PCB
The finished product is a bit ugly, but it works great. Kudos to Jesse and Kaia for leaving room (intentional or not) in the case for stuff on the bottom of the PCB. I threw a bit of super glue on the wires and diodes just to hold them in place, as I don’t quite trust my solder joints for primary support.
If you’re considering replacing a few switches via soldering, I highly recommend learning from my mistakes first, or at the very least, having hope that it can be fixed if you mess up.