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HEX keycaps

HEX keycaps have a low-pro hexagonal profile – designed and manufactured by s-ol and FKcaps for Choc switches.
Published July 7, 2022

New week, new keycap profile. However, this is something different.

In the 0xC.pad/0x33.board post the thing that stuck me first of all, obviously, was the hexagonal keycap/spacing/footprint – potentially a whole new ecosystem.


S-ol has been working on these caps for years with various techniques, e.g. milling and creating molds:


Resulting in promising prototypes:


He has meticulously documented his journey so check out his posts on Mastodon (e.g. this, this and this), and also his blog entry dedicated to molding and casting.

I prototyped the hexagonal keycaps with various milling and casting techniques before partnering with fk-caps to make injection molded parts – s-ol.

So these HEX kexcaps – that's the name both s-ol and manufacturer FKcaps refer to them by – will be available for purchase soon.

I asked FKcaps's Simon for some additional info on this collaboration:

What we intend to do at FK is foster innovation by making designers projects a reality, so while those casted keycaps [in s-ol's original post] were already pretty good, I was thinking that having an enhanced (and "scalable") version of them using injection molding would be next level, and allow for mass production – Simon.

As already mentioned in the 0xC post, instead of a GB model, FKcaps decided to purchase the keycap molds.


According to s-ol, the keycaps in the cover photo above and in the picture below are production samples. "We're very happy with this revision and about to launch the production phase!"


And Simon told me the final version of the keycaps is already being injected and they are waiting to receive the first batch.

[…] I am obviously biased but I am very happy with the result we got both in terms of texture and how light shines through. […] We may plan new iterations with laser-etched black coating (like we did for MBK Glow) – Simon.

With regards to spreading this unique profile, Thomas from SplitKB (long-time donor) is also willing to prepare a PCB for the HEX arrangement, and, as Simon puts it, there is hope that "more designers may join the fun by making other HEX-compatible PCBs".

UPDATE: Product page on

HEX spacing


As you can see, the HEX spacing is quite unique: 21.5mm horizontal and 18.62mm vertical. The exact value was set by experimentation.

It's not based on Choc or MX spacings because there are no PCBs that would be compatible anyway. Even if the Choc horizontal spacing was chosen, for the hexagonal spacing to work, the vertical spacing needs to be a very odd number (width*sqrt(3)/2).

To put it another way, both Choc and MX spacings aren't compatible with an even hexagonal grid. Since no PCB could support both regular keycaps and HEX keycaps, we've decided on a size based on our own testing rather than basing it off of incompatible PCBs – s-ol.

While 21.5mm horizontal spacing is slightly more than MX (19-19.05mm) and Choc/MBK (usually 18-19mm), they can't be directly compared since the vertical spacing is less due to the interleaving effect of the hexagonal grid.


S-ol has put out some resources on his website for everyone to use to build keyboards:

In addition, Simon's (@kartsims at DMs are open to designers willing to build cool custom keyboards based on the HEX keycaps too.

UPDATE: And here is the product page on

Published on Thu 7th Jul 2022. Featured in KBD #86.

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