I had a broken switch. In order to avoid shipment costs from Germany to USA, I tried to solder it on my own. I am not a pro solderer, but some years ago I had to solder VGA adapters as a student.
TL;DR: Only if you are an experienced solderer with high quality equipment. Otherwise, reach out for help.
The board is astonishingly well manufactured. Anyone thinking about replacing a switch should just open the board and have a look in it. In a nutshell: everything looks robust and with quite some room between individual soldering points.
Now comes the uncool part. It seems to be damn hard to get the soldering points right. For one, it seems to me as if the coating of the circuit board melts when one moves the soldering iron next to it. It might just be flux from the tin that dropped, but the white fume/steam I saw did and the surrounding of the holes do just look worrysome.
Furthermore, it seems to be incredible hard to get the tin points good enough. First, when I flipped my circuit board upside down, it the tin just dropped through it. This resulted in a big ball of tin in between the two circuit boards (open your keyboard :-)), which made it hard to remove the switch then. Second, I managed to attach the switch somehow, sometimes even with tiny balls of tin covering the hole in the circuit board. Unfortunately, this was not enough to make the keyswitch work again. Honestly, I am a bit puzzled about how the soldering must be done in order to make electric contact to the board.
Some tips I had to learn the hard way (might seem to be obvious):
- The LED is attached to the circuit board. Checking whether the LED glows is not a sufficient test for correct soldering.
- One can bridge the contacts from the bottom, e.g. by using a paper clip. This might give you a feeling on how you can make electric contact.
- I cannot manage to bridge the contacts from above. Might be some defect I introduced, might be because the circuit board is build back into the housing already, might be impossible at all. Better test before you are not sure whether you broke something.
- Put a printable character to the key which’s switch you exchange before you start.
Two general tips:
- A general soldering tip is to cover the contact wires (the ones coming out of the switch) with tin first. This is common practice e.g. when soldering cables and might help here as well.
- I would recommend using a pliers for removing the switches (after removing the soldering tin, obviously). The force required to remove a switch is not to be underestimated and if you have podgy fingers (like me), that definitely will help.
- edit: I would have found the tool third hand helpful.