How To Replace And Re-Solder A Mechanical Keyboard Switch

Mechanical keyboards are generally touchier than their counterparts, and occasionally a switch will falter. Here’s how to replace it without ditching the keyboard. It takes some tools and a little know-how, but you can absolutely do it.

To take out a switch and install a new one, you’ll need to be able to open the keyboard itself to access the printed circuit board, de-solder the malfunctioning switch with a soldering iron and pump, remove the switch and insert a new one, and finally, solder the new switch into place. If you’ve never soldered anything before, don’t worry. While it helps to have a bit of soldering experience, the soldering you’ll be doing here is pretty straightforward.

What You’ll Need

Before you begin, you’ll need the following parts and tools:

  • Soldering iron
  • Solder pump
  • Electronics-grade solder ($8)
  • Keycap puller tool ($6)
  • Compatible replacement mechanical keyboard switch
  • Small screwdriver and/or pry bar to open the keyboard case
  • Small tweezers or pliers
  • Compatible LED and wire cutters (if the keyboard is lit)

If you don’t already have access to the soldering tools, you can pick up a soldering iron kit that includes the iron, pump, stand/holster, tweezers, and several different tips for less than $20.

WARNING: soldering irons operate at temperatures hot enough to severely burn skin and start fires. Always use caution when operating them, and never leave an active soldering iron outside of its holster. If you continue with this guide, you do so at your own risk.

This guide presumes a basic knowledge of soldering techniques. It’s not particularly hard if you’ve done some work with electronics before, but if you’re not up to speed, check out this article to get informed.

RELATED: How to Use a Soldering Iron: A Beginner’s Guide

Selecting the Right Replacement Switch

Before we start, you’ll need to find a replacement switch for the key that’s malfunctioning. This is more complex than you might think. If your board uses Cherry MX Blue switches, you just have to find another Cherry MX Blue switch, right?

Broadly speaking, yes. Matching the manufacturer and “color” of the switch is the biggest part of getting the feel of the switch right. But you’ll also need to match the specific switch to your specific board. The next big choice is the mount style.

This is referred to as PCB or plate mount: different switch housings are designed to be inserted directly into the keyboard’s circuit board, or onto a metal or plastic plate that sits above the circuit board to protect it. On the left in the image below is a keyboard with plate-mounted switches; on the right, a keyboard with PCB-mounted switches.

PCB-mounted switches include two extra plastic prongs on the bottom for added stability, which aren’t needed for plate mounts. You can generally install a PCB-mounted switch onto a plate keyboard without issue—even if the extra plastic prongs are in the way, you can snip them off and sand them down. But you shouldn’t install a plate-mounted switch directly to the PCB because it will be unstable and more likely to malfunction.

Now let’s talk LEDs. If your board includes lighting, you’ll need to replace the LED, too—they’re not built into the switches. Most commercial keyboards install the LEDs either above the switch, in a specially-formed hollow in the plastic of the switch’s case, or beneath it, directly onto the PCB itself and shining up through a transparent switch case. Here’s a look at the difference:

LED above switch on left, below switch (directly on PCB) on right.

If your board uses LEDs mounted beneath the switch, you’re golden—just leave the current LED in place and install the new switch on top of it. If the LED is mounted above the switch, you’ll need to de-solder the original LED from the board to remove the switch, and re-solder it back in place when you’re done. If you’re careful, you can re-use the original one…but you might want to get a backup LED before you start, just in case.

Finally, if your keyboard uses switches with transparent plastic cases for the bottom-mounted LEDs, you’ll want to get replacement switches with transparent plastic, too. Otherwise the light will be blocked by the opaque switch. These switch variants are often called “RGB,” even though they don’t actually include the LED lights in the switches themselves.

Step One: Disassemble The Keyboard Case

To start this process, remove your keyboard from your PC and place it in a clean workspace. You’ll now need to remove the outer case to access the printed circuit board.

This process will be different for different keyboards. On our example keyboard, a rather typical, mod-friendly Vortex Poker 3 design, all I have to do is remove the keycaps and then remove six screws. If you have a more elaborate gamer-style keyboard, you might need to pry off plastic bits and remove the feet to access retention screws.

A more complex Razer keyboard, with a much more frustrating disassembly process.

As you work, make a note of which particular switch you want to replace. Sometimes the PCBs aren’t labelled, and once the keycaps are off it can be tough to tell one switch from another. A mark on the back of the PCB with a Sharpie won’t hurt.

Once you’ve got the case off, and you’ve removed any cables connecting it to the printed circuit board, you should have something like this: a PCB with a bunch of switches, plus a metal plate if your keyboard uses it.

Step Three: Prepare To De-Solder

Now plug in your soldering iron to warm it up, and get your pump ready. Place your PCB upside down on your work area, with the back of the board facing up and the switches resting on the table. Prepare your sponge or brass for cleaning.

When your iron is hot enough, clean off any oxidized residue so that the tip is clean and shiny. Then press the tip to the electrical prong of the corresponding switch to heat up the old solder until it turns liquid. Be careful not to touch the non-conductive material of the PCB itself, just the solder. Have your pump primed and ready.

When all of the solder is heated and liquified, quickly move the iron away and place the pump on top of the pin. Activate the pump to suck the liquid solder away from the electrical contact before it cools and re-solidifies.

You’ll probably have to repeat the above step two or three times to get all of the old solder away from the electrical contact completely. Do so, then repeat the step for the second contact on the switch. Remember to clean the tip of the soldering iron regularly as you work. Do this again for the pins of the switch’s LED, but only if the LED is mounted above the switch. If it’s mounted below the switch, you can leave the LED in place.

Step Four: Remove The Switch

With the solder removed, you can now physically remove the switch itself. If the keyboard uses PCB-mounted switches, you should be able to simply pull it out with your fingers or small pliers. If the switches are mounted on a plastic or metal plate, you’ll need to depress a couple of small tabs on the switch to release it.

Solder is sticky stuff that dries quickly. If the switch isn’t coming out, it may be because you’ve failed to suck up all of the solder and it’s still retained deep within the electrical contact. Repeat Step Three and try again. You may have to do this for above-switch LEDs, too.

As you remove the LED, if you plan to use it again, make a careful note of its orientation, and place in on the table so you’ll know which pin was placed on which side. If you replace the LED with the anode and cathode pins reversed, it won’t work. When you have the old switch free, set it aside.

Step Five: Install The New Switch

Check your replacement switch, and make sure that its two electrical pins are straight and upright. Now lower it into place onto the PCB. If your keyboard uses a plate, you’ll have to “snap” it down with the electrical pins perfectly aligned. Check it against the other switches to make sure that it’s properly aligned and lowered into place.

Flip the board over. Now you’re going to use your soldering iron to add new solder to the corresponding electrical contact and close the circuit for the switch. Clean your iron, place it on the switch’s first pin to heat up the metal for a few seconds, then carefully guide your solder wire into place so that it melts around the pin and onto the electrical contact.

There should be enough solder melted in place to completely surround the electrical pin, but not so much that it spills over onto the non-conductive material of the circuit board. Clean your iron and repeat the process for the second pin.

If your switch has a top-mounted LED and you’re using the old one, carefully thread it through the plastic switch housing and into the contact holes, making sure to align it as it was before. If you’re using a new LED, do the same, but make sure to align the anode and cathode properly. There should be a guide printed somewhere on the PCB, identifying which hole is positive (anode) and which is negative (cathode). The longer wire is always the anode. You can bend the wires slightly once they’re threaded through the hole to hold them in place while you solder. When you’re finished, if you’ve used a fresh LED, snip the wires close to the solder point.

Step Six: Test The Switch

Without re-assembling the keyboard, carefully move your circuit board with the attached switches back to your computer and plug it in. You can test the switch by simply opening a web browser or word processor and pressing the switch over and over. If the computer is properly registering the keystrokes, you’re ready to go. If it isn’t, you haven’t correctly completed the circuit with your solder, and you’ll need to go back through the steps above to see where you went wrong.

Step Seven: Re-assemble Your Keyboard

Remove the keyboard from your PC again. Place it back in its case and close it up, reversing whatever process you needed to take for your specific keyboard in Step One. Replace the keycaps, move back to your computer, and plug in the keyboard. You’re ready to go.

Image credit: WASD Keyboards, Deskthority, AliExpress, iFixIt

Michael Crider has been covering technology on the web since 2011. His interests include folk music, football, science fiction, and salsa verde, in no particular order. He wrote a novel called Good Intentions: A Supervillain Story, and it's available on Amazon. You can follow him on Twitter if you want.