Soldered Build Guide: Traditional Assembly
For many enthusiasts, soldering is a core part of the custom keyboard experience. It's a rewarding skill that creates a permanent, robust, and reliable electrical connection between your switches and the PCB. This guide will walk you through the process safely and effectively, ensuring a build that will last for years.
Soldering may seem intimidating at first, but with proper preparation and technique, it becomes a meditative and satisfying part of the build process.
The Traditional Build: Soldered Assembly
For many enthusiasts, soldering is a core part of the custom keyboard experience. It's a rewarding skill that creates a permanent, robust, and reliable electrical connection between your switches and the PCB. This guide will walk you through the process safely and effectively, ensuring a build that will last for years.
Prerequisites:
- You have all the tools from our Tools and Preparation guide, including the soldering-specific items (soldering iron, solder, solder sucker, and safety gear).
- Crucially, you have tested your bare PCB with tweezers to ensure every key registers correctly before you begin soldering. This is your last chance to easily identify a faulty PCB.
Step 1: Prepare and Install Stabilizers
This step is identical to hotswap builds but is arguably even more critical for a soldered build, as you cannot easily remove the stabilizers after soldering. A well-lubed stabilizer is crucial for premium sound and feel. Disassemble, lube (as described in the hotswap guide), and mount your stabilizers to the PCB before you do anything else. Double-check that they are securely snapped or screwed in place.
Step 2: Mount Plate and Install Corner Switches
- Place the switch plate over the PCB, carefully aligning all the holes.
- Take 4-5 switches and install them at the corners and in the center of the board. Push them firmly through the plate, and ensure their metal pins go all the way through the corresponding holes in the PCB. The switches will now hold the plate and PCB together in alignment.
- Flip the entire assembly over, resting it on a stable, heat-proof surface. The pins of the corner switches you installed should be sticking out through the back of the PCB, ready for soldering.
Step 3: Solder the First Switches (The "Tacking" Phase)
This is the critical step to lock the plate and PCB together accurately. By soldering just one pin on each of the initial switches, you can verify alignment before committing.
- Set Your Iron Temperature: A good starting point for lead-free solder is around 350-380°C (660-720°F). For leaded solder, 320-350°C (600-660°F) is sufficient. The key is to be hot enough to melt the solder quickly without dwelling on the joint for too long.
- "Tin" Your Iron Tip: Before you start, melt a tiny bit of solder directly onto the tip of your clean iron. This is called "tinning" and it helps with heat transfer. Wipe off the excess on a damp sponge or brass wool, leaving a thin, shiny layer.
- Heat the Joint: Touch the tip of your soldering iron to the junction where the switch pin and the circular metal pad on the PCB meet. Hold it there for about 2 seconds to heat both components simultaneously. Heat the components, not the solder.
- Apply Solder: While keeping the iron on the joint, touch the tip of your solder wire to the opposite side of the joint (not directly to the iron tip). The heat from the pin and pad will melt the solder, and it will flow into and around the joint, creating a strong bond. You only need a small amount—just enough to form a clean, shiny, volcano-shaped cone.
- Remove Solder, then Iron: Remove the solder wire first, then immediately remove the soldering iron. The whole process should only take 4-5 seconds per joint.
- Solder just one pin on each of your corner/center switches. Then, flip the assembly over and carefully inspect it. Is the plate perfectly flush with the PCB? Is there any gap? If it's not perfect, you can easily re-heat the few joints you made and adjust the alignment.
Step 4: Install and Solder the Remaining Switches
- Once you've confirmed the alignment is perfect, install the rest of your switches into the plate, ensuring each one is fully seated.
- Flip the assembly back over. Now, work your way methodically across the board, soldering both pins of every switch. Take your time and focus on creating clean, consistent solder joints. A good rhythm is: heat joint, apply solder, remove solder, remove iron.
- Inspect Your Work: As you go, or after you finish, look for common soldering issues:
- Cold Joints: These look dull, blobby, and haven't flowed correctly. They make poor electrical contact. To fix, simply reflow them by re-heating the joint with the iron until the solder becomes shiny and flows properly. You may need to add a tiny bit more solder.
- Bridges: This is when solder has accidentally connected two adjacent pins (e.g., the two pins of a switch, or a switch pin and a diode). To fix, heat the bridge with your iron and use a solder sucker or solder wick to remove the excess solder.
Step 5: Trim LED Legs (If Applicable)
If you installed through-hole LEDs for backlighting, they are soldered just like switches. After soldering, use your flush cutters to trim the excess leg length. Be careful of flying bits of metal—wear safety glasses!
You've completed the most challenging part of the build! The result is a rock-solid keyboard. Now, let's move on to the Final Assembly and Testing.
External Resources