Building a split keyboard (and why you might want to do it)

Published on 5/25/2025 · 11 min read

Why I Built My Own Split Keyboard: A Journey to Comfort and Efficiency

For years, I typed on Apple’s Magic Keyboard, and never questioned using another type of keyboard, until I came across split keyboards, randomly through a friend. Before that, I never got convinced by the ergonomic keyboards I ran into: they would usually feature a slight curve in their key layout and some wrist pads. Yet seeing a keyboard truly split in two parts, along with column-staggered layout, I started digging into the world of ergonomics, a world much deeper than what I imagined. I began understanding the discomfort I’ve been maintaining so far. After long coding or writing sessions, my shoulders ached, hunched posture forced by the keyboard’s narrow layout. My hands, cramped together, seemed to amplify tension rather than productivity. Moreover, despite years of typing, I still found myself glancing down at the keys, struggling to build muscle memory. The excessive key travel and staggered rows meant my fingers had to wander too far, breaking my flow.

So it was time for a change. Split keyboards promised relief by letting my hands rest at a natural shoulder-width distance, but the pre-built options were either prohibitively expensive (like the $300+ Moonlander or Advantage360) or bulky (such as the Glove80, which seems fantastic but hardly portable). Frustrated, I stumbled upon the vibrant world of DIY mechanical keyboards, and it felt like a revelation.

The community had already solved my problem. Dozens of open-source keyboard designs existed, with passionate builders sharing schematics, firmware, and modding tips. After weeks of research, I fell for the Ferris Sweep: a sleek, ultra-compact and minimalist 34 keys split keyboard with a column-staggered layout designed for ergonomic typing. It checked every box—portable, cheap to make, and painstakingly optimized for efficiency.

Building it myself wasn’t just a cost-saving hack; it was a deep dive into a hobby that blends engineering, ergonomics, and sheer creativity. Here’s why I chose it, how I built it, and what I’ve learned after a year of daily use.

Why the Ferris Sweep Bling LP Won Me Over

The Ferris Sweep Bling LP, from David Barr based on the work from Pierre Chevalier, wasn’t just another keyboard, it was a deliberate answer to my ergonomic and practical needs. Here’s why it stood out:

1. Ergonomics, Optimized
The split design freed my hands to rest at a natural shoulder-width distance, eliminating the shoulder strain I’d endured with traditional keyboards. Paired with an ortholinear, column-staggered layout, it minimized finger stretching by aligning keys to my fingertips’ natural movement.

2. Ultra-Portable, Ultra-Sleek
With only 34 keys and low-profile Choc switches, the Sweep’s entire body sits under 22mm tall. It’s lightweight and compact, making it easy to toss in my bag and to fit anywhere, even on cramped coffee shop tables. I 3d-printed two custom cases that adds minimal bulk while protecting the internals: a long but thin one and a smaller but thicker one.

3. A Community-Backed Build
From firmware tweaks to Bluetooth mods, the Ferris Sweep’s open-source roots meant I wasn’t alone. Forums and GitHub repos overflowed with keymap inspiration, troubleshooting tips, and even hardware upgrades (like my eventual leap to wireless). That safety net gave me confidence to tinker.

4. Budget-Friendly Minimalism
While Choc switches cost more than Cherry MX, the Sweep’s radical minimalism helps bringing costs down. For under $150, I built a keyboard that rivaled $300+ pre-built splits.

What to Consider When Choosing a Keyboard

Building your own keyboard is a rare chance to craft a tool that fits your exact needs—but with so many options, it’s worth reflecting on what truly matters to you. Here’s a breakdown of key factors to weigh before diving in:

1. Ergonomics: Split, Layout, and Shape

Since ergonomics drove my search, I focused solely on split keyboards, but even within that category, choices abound:

• Layout & Number of Keys:
  • Prefer a familiar layout? Keyboards like the ZSA Voyager, Lily58 or Sofle offer split designs with standard key counts.
  • Want radical minimalism? My 34 key Ferris Sweep forced me to think thorougly about my key mappings, and to embrace layers. It was a steeper learning curve, though it felt rewarding.
• Curved or Flat?
  • Keyboards like the Glove80 or Kinesis Advantage360 curve keys to further reduce finger motion. While tempting, their bulk clashed with my need for portability, though I’d love to try one someday for home use.
• Tenting (Adjustable Inclination):
  • Some keyboards like the Moonlander include built-in tenting. For DIY builds, if you have access to a 3D printer, you can find tenting accessories to print. I tried [this one] for the Ferris Sweep, but didn’t stick to it (yet?).

2. Budget: DIY vs. Pre-Built

• DIY keyboards are often far cheaper. My Ferris Sweep cost under $100, while pre-built ergonomic splits can exceed $300.
• Some shops (e.g., Mechboard, SplitKB) sell pre-soldered DIY kits at a slight premium, saving time without breaking the bank.
• If budget isn’t a constraint, the ZSA Voyager or Kinesis Advantage360 are solid options.

3. Switch Type: Feel and Flexibility

• Choc Low-Profile vs. Cherry MX: I chose Kailh Choc switches for their slim profile, though they’re pricier than Cherry MX.
• Hot-Swap matters: As a newcomer to mechanical keyboards, I prioritized hot-swap sockets to experiment with different switches without resoldering.

4. Build Difficulty: Time vs. Reward

• Soldering Required? Most builds (like mine) need basic soldering. Thankfully, it’s beginner-friendly.
• RGB/Backlighting: It can be really nice, but it adds complexity (and cost). I skipped it because it wasn’t essential to me.
• No Tools? Opt for a pre-soldered PCB or a hot-swap kit to avoid soldering entirely.

5. Firmware & Programmability

• QMK/ZMK Compatibility is non-negotiable for me. These open-source firmware systems let you create custom layers, macros, and even wireless support (via ZMK).
• Pre-Built Convenience: If coding keymaps sounds daunting, pre-builts often include user-friendly configurators (e.g., ZSA’s Oryx). Coding might be utterly unnecessary if you pick a keyboard with enough keys for your needs (Sofle, Lily58, Glove80, …).

Bill of Materials & Cost

I built two versions of the Ferris Sweep Bling LP: a wired home setup and a Bluetooth travel companion. Below are the components for one build (total: ~$140 wired / ~$150 wireless), with notes on where I saved or splurged:

Core Components

• PCB: Ordered from JLCPCB using David Barr’s open-source design ($15–25 for 5 boards).
• Microcontrollers:
  • Wired: 2x ProMicro RP2040 ($5 each).
  • Wireless: 3x NRF52840 ($3 each; 2 for halves, 1 optional for USB dongle).
• Hotswap Sockets: 34x Choc hotswap sockets like like these ($5/100).
• Switches: 34x LowProKB Ambient Twilight (silent Choc Reds, $60/35—my splurge!). Cheaper options exist.
• Keycaps: 34x like these ($25/50).
• 2 power switches: 10 MSK-12C02 ($1.50/10).
• 2 reset switches: 10 B3U-1000P ($3.50/10).

Wired vs. Wireless Add-Ons

• Wired: TRRS jacks ($2/10) + cable ($2.50).
• Wireless: 2x LiPo batteries like these ($8 each; 3-month battery life).

Optional Upgrades

• Mill-Max Sockets and Pins ($11): for instance these pins with these sockets. Lets you swap controllers (e.g., wired → wireless) without rebuilding. (See tip below!)
• 3D-Printed Case: Print your own or buy one for protection.

Build Tips & Lessons Learned

1. Socketing Controllers:

   • Use a breadboard + tape to align Mill-Max pins before soldering (see image below). A magnet helps collect stray pins!
     

2. Battery:

   • ⚠️ Always tape one LiPo wire while soldering to avoid shorts. Store spares in a fireproof bag.
   • Trying to raise the distance between the controller and the keyboard is a good idea to fit thicker, and therefore higher capacity, batteries. That’s another advantage of the Mill-Max sockets.

3. Wired or wireless?:

   • I started with a wired build, then built another wireless one. The wired build is perfect for home use, while the wireless one is great for travel.
   • One issue with many wired builds is that they use a TRRS cable to connect the two halves, which can unfortunately lead to a short if it is unplugged while the keyboard is powered on. That’s pretty unforgiving, I learned it the hard way by frying a controller… Another good reason to socket the controllers!
   • For wireless builds, consider using a USB dongle. It significantly improves battery life.

4. Cases Matter:

   • A case protects the PCB and adds grip. I 3D-printed mine, but pre-made options exist.

(For a full build guide, see Kyek’s YouTube tutorial.)

One Year With the Ferris Sweep: Comfort, Customization, and Compromises

From Daunted to Devoted: The Learning Curve

When I first started to use my 34 key Ferris Sweep, I stared at the bare PCB like it was a puzzle. How would I code without dedicated keys for numbers or symbols? But the open-source community came to the rescue, with many keymaps I could draw inspiration from. My main use case is coding, so I focused my keymap on facilitating Vim motions and access to symbols. My current keymap can be found here for QMK and here for ZMK.

The adaptation was shockingly fast:

• 1 week: Nearly back to my original typing speed (since only symbols/layers needed remapping).
• 1 month: Fully fluent with home-row modifiers (Shift, Ctrl, etc. under ASDF/JKL;). No more pinky gymnastics for Shift and Ctrl!
• 3 months: Added combos (e.g., J+K for Esc, E+R for Tab, U+I for Caps Lock, Space+Backspace for Enter, …) and tap-dance (double-tap thumbs for layer toggles).

The Ergonomics Payoff

Speed wasn’t the goal, endurance was. Mission accomplished:

• ✅ No more shoulder pain from cramped hands.
• ✅ Mechanical bliss: Choc switches’ low profile and quiet clicks ruined rubber domes forever.
• ✅ Layers > Stretching: Symbols and numbers live on thumb-activated layers, reducing finger travel.

Where the Ferris Sweep Falls Short

It’s not perfect, but the tradeoffs were worth it for me:

• Thumb Keys: Two per side works, but a third (like on the Corne or Swoop keyboards) could be a nice addition for Tab/Enter or Shift.
• Gaming: Home row modifiers doesn’t play nicely with gaming, and you may miss the top number rows. I still use my old Magic Keyboard for gaming, but it’s a minor inconvenience considering how rarely I game.
• French Accents: My mapping ignores them (I write mostly in English), but adding a dedicated “accent layer” is doable, just not my priority.

Final Verdict

The Ferris Sweep forced me to type smarter, not harder. A year later, I’d choose it again for its portability, ergonomics, and the joy of a truly personalized tool. But if you game often or need heavy language support, other keyboards might suit you better.

Conclusion: A Journey Worth Taking & Where to Next

Building the Ferris Sweep was my gateway into the vast, endlessly creative world of keyboard ergonomics, a world I now realize I’ve only begun to explore. From tenting to curved key wells, or even mounting halves on my chair’s arms, there’s so much left to experiment with. But one lesson stands above all: our default keyboards are relics of the past, and settling for them means ignoring decades of ergonomic progress.

The QWERTY Elephant in the Room

The biggest bottleneck to comfort and speed isn’t just the keyboard’s shape: it’s the QWERTY layout itself. Designed to slow down typists on mechanical typewriters, it forces awkward finger movements that even the best ergo boards can’t fully fix. Switching to Colemak or Dvorak feels inevitable now, though I’ve hesitated (thanks to occasional laptop use). But someday soon, I’ll take the plunge—because why optimize the hardware without refining the software?

A Call to Action

Let’s be honest: soldering diodes and tweaking firmware isn’t for everyone. But if you spend hours daily at a computer, investing in a split ergonomic keyboard (DIY or pre-built) is one of the highest-return upgrades you can make. Shoulder pain, wrist strain, and inefficiency aren’t inevitabilities: they’re design failures we’ve tolerated for too long.

The Ferris Sweep taught me that typing shouldn’t hurt. It shouldn’t feel like a chore. And with a little curiosity, it can even become a joy. So to anyone still pecking at a flat, cramped keyboard: your hands deserve better.

(Want to start your own journey? Check out the open-source Ferris Sweep repo or communities like r/ErgoMechKeyboards.)