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Infernum is a sub-40% keyboard with Katana layout – designed by Hai_Zeus.
Published September 9, 2022

The Infernum, this sub-40% monoblock split(?) by Hai_Zeus (top photo by wayduh) features the long-time not seen Katana layout.

Here goes a little sneak peek on a project I've been working on. It's a katana stagger sub 40% keyboard running on Vial-QMK – Hai_Zeus.

Katana was a family of keyboards designed by RominRonin back in 2016/17 in the picturesque Vienna – so it's not authentic Japanese despite the name choice. Most notable of the various versions is probably Katana60 which went into production and is still available e.g. here.

For those who are not familiar with this arrangement, it's a horizontally staggered layout but symmetric at the same time. Somewhat confusing to write about because the halves are not angled (horizontal rows) but you hold your forearm at an angle, wrist extension is alleviated.

Many years ago, as a noob in custom mechanical keyboards, Katana was one of the first layouts that actually made sense to me.

Anyway, Hai_Zeus came up with something similar on a 30-40% scale: ditching some keys, especially the number row and the hard-to-reach middle ones, and putting the ambiguous inverted cross symbol there – probably that's why wayduh chose the leviathan cross to make things clear. :D

The current design is Pro Micro based with a 3D printed case, but the author's plans are an integrated PCB running on an RP2040 microcontroller and milled acrylic or aluminum case.

Published on Fri 9th Sep 2022. Featured in KBD #94 (source).

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