[Build Log] K-4398


Hey there! Welcome to another build log. :grin:

Took a peep at my Eighty #391 Build Log, and I’m realizing my tastes have expanded, but haven’t changed much over the years.

’Chew’s Keeb Interests

  • Sizes, Layouts: TKL, 90%, Alice (with F-Row)
    • Non-Negotiable: ANSI, Function Row, Special / Edit Keys
  • Case: Metallic Construction, High-Profile, Angled, Matte Black
  • Plate: Black / Frosted / Transparent
  • PCB: Hotswap, QMK / VIA Compatibility, Black
  • Switches: Linear, Silent Stems, 150g Springs
    • Non-Negotiable: Black Housings
  • Stabilizers: Black
  • Keycaps: Blank, PBT, OEM-Profile, Matte Black
  • Acoustics: Silent, Thock / Clack

TLDR: Black Aesthetic, Heavy Silent Linear Switches.

qwertypop happened to advertise the 4398 Keyboards they had in stock on Mech Group Buy’s Discord, and I happened to be paying attention, and the 4398 Keyboard happened to check off my preferences.

Fast forward a few days later, aaand it’s in my hands!

I pity the fool that misses the in stock listing and Group Buys it later.

黒-4398 ⇒ くろ-4398 ⇒ Kuro-4398 ⇒ K-4398
(黒 = Black)

Couldn’t think of any clever, meaningful wordplay with “98,” so I kept it simple.
[Begrudgingly puts away list of 'Chewnibyō chūnibyō names.]
(Pun stolen from Den.) :derpdorp:

Parts List

Component Selection Price
PCB 4398 Keyboard Hotswap PCB
- Poron Switch Pads
- Stabilizer Foam Pads
≈ $345.00
Case 4398 Keyboard Case (Anodized Aluminum, Black)
Mounting Plate Custom 4398 Keyboard POM Mounting Plate
4398 Keyboard Polycarbonate Mounting Plate
Switches Modded Silent POM Switches (210g)
- Durock POM Switch Housings
- Gazzew / Outemu Silent Linear Stems
- SPRiT MX Supreme Springs (210g)
- Krytox 205g0 Lubricant
Stabilizers Durock Screw-In Stabilizers (V2) $25.00
Keycaps POM Ink Keycaps
- Spacebar Foam

EnjoyPBT Blank Black PBT Cherry-Profile Keycaps
Cable CableMod Custom Pro Coiled Cable
- Dual-Sleeved (Black ModMesh Nylon, Black ModFlex Paracord)
- GX16 Aviator Connector (5-Pin)
- Cerakote Coating (USB-C, USB-A, Aviator QDC)
Grand Total
(Shipping, Taxes, Foreign Transaction Fees Excluded)

Parts Update History

Last Updated: 07/28/2022
  • [07/18/2022]: Initial Build - K-4398
  • [07/21/2022]: Remapping via VIA - VIA + 43_980.json File
  • [07/28/2022]: POM POM POM - POM Mounting Plate + POM Ink Keycaps


4398 Keyboard Kit

Keyboard Kit Parts

  • 1 × 4398 Keyboard Top Case + Bottom Case / Weight
  • 1 × 4398 Keyboard PCB
  • 1 × Poron Foam (3.5mm)
  • 120 × PE Foam Switch Pads
  • 1 × Winkey Blocker
  • 3 × Black Keyboard Accents
  • 3 × Frosted Keyboard Accents
  • 1 × 7U Stabilizer Wire
  • Screws, Bumpons, Etc.

Other Essentials (Separate Purchases)

  • 1 × 7U Stabilizer, 6 × 2U Stabilizers
  • 102 Switches (ANSI Layout)
  • 102 Keycaps (ANSI Layout)
  • USB Type-C Cable

PCB + Switch Pads + Stabilizers
Don’t look at the up arrow key.
Now you can never unsee it.

Assembled PCB + Poron Foam + Mounting Plate
Instantly sold on plastic mounting plates.
For one, they don’t attract fingerprints as much as polished metal does. :laughing:

Assembled PCB / Foam / Plate + Switches
Keyboard Checker time!
Branded cable (temporary setup) came from erm, a Razer Zephyr mask that I got for free. :joy:

Assembled PCB / Foam / Plate + Top Case
4 × Tiny Hex Screws to mount the plate to the top case.
Mounting feels easier and more secure compared to Eighty #391. :eyes::sweat_drops:

K-4398 - Bottom Weight / Case
8 × Tiny Hex Screws to secure the bottom weight to the top case.

K-4398 + Modded Silent POM Switches (210g)
I’ll be honest, bottoming out is really difficult now. :rofl:
Oh, and the spacebar is actually 180g because I didn’t have enough 210g springs. :smiling_face_with_tear:

K-4398 - Assembled!
First order of business:
Disable LEDs. :joy:


Sound Samples

Sound samples recorded with the Antlion Mod Mic and Audacity.

Modded Silent POM Switches (210g) (Fast)

Modded Silent POM Switches (210g) (Slow)

Closing Comments

It’s been a very long while since I’ve been excited about custom keebs again. Day in, day out, it feels like I’m staring at samey listings by vendors offering similar inventories. And if something’s locked behind a Group Buy, my interest falls off exponentially rapidly.

The easiest way to rope me into another keeb purchase?
In stock and immediate shipping.
Also, have someone competent designing the keeb, lol.

Even better if it’s limited in quantity. Mmm yaaaaaaaaaas, give me that intangible and trivial sense of self-worth that comes from possessing something that the greater majority does not or can not have.

Current Desk Setup

The plan for K-4398 was to deck it out as much as my patience allowed:

  • Gazzew / Outemu Silent Linear Stems: Transferred all of these over from Eighty #391 to the new build, since I’ve grown incredibly fond of them. Oddly enough, I had 102 stems – exactly enough to outfit K-4398 (ANSI layout).
  • SPRiT MX Supreme Springs (210g, 180g): Finally acquired these. Only for the truly cultured and masochistic, kek.
  • Switch Pads + Stabilizer Pads: Uncertain how significant of an effect the pads have on the 4398 Keyboard’s typing / acoustic experience, but it’s a cheap addition and doesn’t detract from the keeb, so why not?
  • Stabilizers: Stabilizer rattle was, admittedly, one of the problem areas with the Eighty #391 that I never got around to fixing. Made it a point to tune K-4398’s stabs to my liking this time.
  • Durock POM Switches: There’s a theme I’m going for here, the rest of the pieces haven’t reached my hands juuust yet. :eyes:

Aat some point, gotta fiddle around with QMK / VIA because Scroll Lock, Pause, and Num Lock are useless to me.

Why does perfecting something have to take so loooooooooong, I just wanna play gaaaaaaaaaames. :tired_face:

Eighty #391

Eighty #391 - Barebones

Will now be retired and safely stored away in its keeb bag.


Two things:

  1. You’re super cute.
  2. 142 WPM @ 210g is witchcraft.

K-4398 Update - Remapping via VIA
VIA is an application / program that lets users remap keys, toggle between layouts, add macros, and control lighting for supported QMK-compatible keyboards.

  • VIA has a simple GUI and is intuitive to use for anyone that isn’t familiar with (or is daunted by) QMK MSYS, QMK Toolbox, and the process of flashing a keyboard.
  • Any edits made in VIA will be immediately applied to the keyboard in use.
  • As a tradeoff, VIA’s capabilities aren’t as extensive, compared to customizing keymaps with QMK. For instance (IIRC), VIA is limited to 9 layers, while QMK will work with up to 16.
  • Not all QMK-compatible keyboards are supported by VIA. Supported keyboards are listed on VIA’s site (Supported Keyboards).
  • For layout .JSON files, VIA’s .JSON files are not compatible with QMK Configurator’s .JSON files, and vice versa.
  • Keymap .JSON files may be compatible between VIA and QMK Configurator – with some manual editing – but I haven’t tested this theory.

VIA Website: https://www.caniusevia.com/

VIA Tutorial / Step-by-Step

  1. Download and install VIA from the-via/releases.
  2. Launch VIA (VIA.exe).
    • Default file directory is C:\Users\...\AppData\Local\Programs\via.
  3. Import the keyboard’s .JSON layout file via File > Import Keymap.
  4. Start remapping keys to your liking. Changes are applied immediately.
    • MO(1): Toggles between layers.
  5. Simply exit VIA when finished, no saving necessary.
  • Save + Load: Options here will save and load .JSON keymap files specifically for the current layout. Attempting to File > Import Keymap .JSON keymap files will not work.
    1. Import the keyboard’s .JSON layout file via File > Import Keymap.
    2. Load the keyboard’s .JSON keymap file via the Save + Load tab.

Remapping K-4398
Initially, I couldn’t find the 4398 Keyboard’s QMK files / VIA files. It was clearly advertised as QMK / VIA compatible, but curiously wasn’t listed on either QMK Firmware’s All Supported Keyboards or VIA’s Supported Keyboards lists.

So I asked for help in qwertypop’s Discord server, aaand…

Very thankful for qwertypop’s responsive team!
The alternative was to install AutoHotkey but I really didn’t want to have that running in the background all the time.

4398 Keyboard - Default Keymap (Layer 0)
A pretty conventional layout, with some problematic placements in the top-right.
Why is Delete and Home up there.
Scroll Lock and Pause are useless, please.
Excuse me, where is my End key?

K-4398 - Edited Keymap (Layer 0)
Much more to my liking and use case.
Customization is such a blessing.

4398 Keyboard - Default Keymap (Layer 1)
Nothing immediately offensive on this layer, so I’ll leave it be.
Psych, made some slight edits to Layer 1.

K-4398 - Edited Keymap (Layer 1)
Honestly I don’t use Insert, Pg Up, or Pg Dn often, but sometimes games (looking at you, Dragon’s Dogma) insist on using these keybinds. :tired_face:


K-4398 Update - POM POM POM
So… I have a one-track brain…? :derpdorp:

New Stuff!
1 × POM Ink Keycap Set
1 × POM Mounting Plate
1 × POM Wonderful Pomegranate Juice

POM caps and POM plate were from Den! Thank you again! :heart_eyes:

Custom POM Plate by Green Door Geeks!

It is B L A C K.
Lotsa scratches / heat marks, which I’m told is the norm for custom-cut POM plates.

4398 Keyboard Polycarbonate Plate + Custom POM Plate
This thing is shiiiny.
Shiny = Fingerprint Magnet.
[Slaps on gloves.]

4398 Keyboard POM Plate + Polycarbonate Plate
Role reversal, kek.

K-4398 + Switches


LIKE THIS? (Den Pics!)

:wubba: Den’s 4398 Keyboard! :parrotheart:

Spacebar Foam
Thanks for the reminder, Tatsu, very helpful.
(Tatsu did not remind me. :roll_eyes:)

K-4398 + Keycaps
POM Plate + Modded Silent POM Switches (210g) + POM Ink Keycaps
I have a one-track brain okei, pls no bully. :tired_face:

4398 Keyboard + POM Ink Keycaps - Close Up
:pepesaber: OEM profile, best profile. :pepesaber:
Also, my photos and lighting are garbo, but the color match is freaking .

Better Pics (Den Pics!)

Den’s 4398 Keyboard!

Sound Samples
Sound samples recorded with the Antlion Mod Mic and Audacity.

Modded Silent POM Switches (210g) (Fast)

Modded Silent POM Switches (210g) (Slow)

First time tasting POM Wonderful Pomegranate Juice, though I’ve seen it around n’ about. Very dark in color (don’t spill on whites ), and very tart. Starts to smell more unpleasant the longer it’s left out in the air, but tastes fine (IMO). I’d… eh, still prefer good ol’ pulpy orange juice over pomegranate juice, lol.

Apparently POM Wonderful is a Cali brand, neato.


No, no more keyboards, this is endgame. End Game. エンド・ゲイム.
E-N-D G-A-M-E.
Please be endgame. :joy:

Tho, I mean “endgame” with the best possible connotation, 'cos this build / recent update actually includes one of my personally most sought after item(s): the POM Ink keycap set. As far as I’m aware, they’re only available from ESC Keyboards, based in Australia. The price tag is whatever, but sweet mother of damn that shipping fee.

I’ve sent polite emails to a handful of regional vendors with my interest in the POM Inks, but no one in the U.S. seems keen on stocking them. It is what it is, I guess.

Then somehow one thing led to another and POM Inks arrived on my doorstep.
Thaaaaaaaaaank yooooooooou Dennnnnnnnn!

Saying that I’m incredibly happy with the K-4398 would be an incredible understatement. I don’t think I’ve derived this much satisfaction from a keeb build, not even after Eighty #391.

Current Desk Setup
Don’t say it’s the same picture, it’s not the same picture damn it. :rofl:
Look at those keycaps.

It’s silent, it’s color coordinated, it’s heavy enough to cave someone’s skull in (probably?).
Its layout feels comfortable and natural to my fingers, and in the event it’s not, it’s fixable with a quick hop into VIA.

It is – currently, at least – everything I want from a keeb. :smiling_face_with_three_hearts:
Let this be endgaaaaaaaaame, please lmaooo.
Absolutely do not come up with a full-sized, southpaw, QMK-compatible keeb.