Fixing Keychron K3 brown switch

K3E3

(c) keychron.com

I backed Keychron K3 on Kickstarter, and after a long wait, I received the keyboard with brown optical switches (K3E3 modification), which is pretty awesome except for one nasty tiny detail: the keystroke registers far before the tactile bump.

Here is the illustration of the fixing method, which was also described on reddit.

The first switch took me some time to understand how it works. It is not very difficult to disassemble, but losing some parts is easy. So before the start, I highly recommend placing the patient switch inside a highlighted cardboard box and keeping it there while working on it. Seriously, consider working inside the cardboard box. You might lose very tinny parts like spring or stem; otherwise, they can jump away quickly, and the box will help to contain them.

Keychron brown optical switch
Keychron brown optical switch

 1. Take a look at the bottom of the switch:

Bottom of K3E3 switch
Bottom of K3E3 switch
The red circle shows where the stem breaks the light beam when the key is pressed. We will remove it. You don’t need to open the switch yet.

 2. Press the switch.

Pressed K3E3 switch
Pressed K3E3 switch
The stem will move closer to the bottom of the switch.

 3. Use tweezers or another appropriate tool to press the stem out of the housing.

Top of K3E3 switch
Top of K3E3 switch
Taking the stem out
Taking the stem out
While taking the stem out, keep the switch in your hand and make sure that the stem will fall out in a box / safe place.

 4. Keep the stem in a safe place for a moment.

Stem of K3E3
Stem of K3E3
Stem and spring separated
Stem and spring separated

 5. Now use tweezers to open the switch.

Opening of K3E3
Opening of K3E3
Opened of K3E3
Opened of K3E3
Please don’t move the spring you see in the open switch. They need to be left in their places. The big spring is creating the actuation force. The small spring is responsible for creating a tactile bump.

 6. Now take the stem without the spring and insert it from the bottom of the switch.

Inserting the stem into K3E3
Inserting the stem into K3E3
Opened K3E3 switch
Opened K3E3 switch
Then place the small spring from the inner side of the switch bottom.

 7. Now pre-insert the brown part back into the place, but do not press fully yet. We need to move the tactile spring to the correct position.

Preinsertion
Preinsertion
Placing the tactile spring
Placing the tactile spring
Full press
Full press
Closing
Closing
When fully pressed and tactile spring on place, secure the stem in the brown part pressing from the bottom side with tweezers. And finally, close the switch entirely. The upgrade is finished.

This post was typed on the upgraded K3E3. The fix took about 4 hours and improved typing speed by a factor of two, and reduced the error rate by a factor of 6.

Misha Usvyatsov
Misha Usvyatsov
General Chaos (Software Engineer)

I am interested in tensor decompositions applications, deep learning and low-level programming.