Kailh Sun Switches are Great



This is Maabi. I joined Yushakobo in March, but COVID came and the shop closed. It's really a shame. But we're still working despite not being at the shop, and this entry talks about one of the things I've been working on


What is the Kailh Sun Switch?

Did you know about the Kailh Sun Switch (Sun switch for short)?

They can be found in the online shop in pack of 10.



I love clicky switches, and have used mostly Cherry MX blues and Razer green switches, so naturally I'm drawn to the Sun switch.

It is created for under-switch LEDs to shine through them when lit, with gamers in mind. Gaming keyboards all have lights, so...

But it would be boring to only talk about lighting, and certain that doesn't deserve an entry on its own. So what's special about the Sun switches?


This switch only has 2 pins, and does not have the plastic pins that secure the switch to the PCB. So it requires a plate to be secured in place, whereas the 5-pin switches can do just fine even without a plate.

The Sun switch has a larger spring as well. I wonder if it's because they originally planned to put LEDs inside the switches. Either way, it makes the click feel very smooth.

The switch is also, strictly speaking, not "fully" MX-compatible. It takes MX keycaps just fine, but it cannot use the MX switch footprint on the PCB side. This means PCBs must be specifically made to use these Switches, making them a little harder to sell despite being amazing switches.


So I made some PCBs.



PCB design on 3D viewer


Luckily, my boss has made a footprint for the Sun switch, so I created a tenkey layout with it, with surface-mount LEDs. This is what I got from the PCB manufacturer:


Finished PCB


Looks great, right? Just solder everything and it should work!



The USB cable can't reach the Pro Micro!

Ugh. A design error.


Through-hole diodes will st

op the switches from being soldered properly!

Ugh ugh.


The hole size for the LEDs aren't precise so they can't be inserted!

Ugh ugh ugh.



Anyway, stay tuned for my next project!



Yushakobo, a DIY keyboard shop