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the Heavy Grail

the Heavy Grail


The Happy Hacking Keyboard has a new home.

An aftermarket upgrade kit for the HHKB (Pro 2 and Pro 3)

"...a massive feat of engineering and a spectacle to behold..."
—Material Journal

"Ooh lala. It sounds perfect and is a great weight. ... How could I not love it?"
—Olivia (of GMK Olivia and Olivia++)

"As ever, the product and packaging are unmatched. Immaculate."
—@jblanton on Twitter

"I am in love with it."
—Ral on Keebtalk

"probably the most premium feeling kit I've had the pleasure of laying my hands on"
—winbear.builds on IG

"The piece that elevates this board to the unequivocal pinnacle of my collection (with no exaggeration) is the nearly obsessive extent to which Ryan invokes the HHKB typing experience with this case’s acoustics and flexibility."
—bongounicorns on Keebtalk


My job is to take the most beloved keyboards in the world and design their dream homes: housings that upgrade humble stock injection-molded encasements into meticulously crafted, CNC-machined art objects.

I've been at this for nearly 8 years, and whenever I go to keyboard meetups, speak at events, or otherwise interact with my fellow typing nerds, I've gotten one question more than any other: when will I offer a case for the venerable HHKB? It has seemed an almost insurmountable technical challenge, but I am happy to say that I now have an answer to that recurring question: today.

Meet the Heavy Grail, available in powder-coated aluminum or hand-polished stainless steel.

At every step in the process of its creation, I've chosen the pursuit of perfection over cost or expediency, because there is no point investing so much into solving one of the hardest problems in the keyboard world and not doing it properly. The result is a quixotic exercise in lavish keyboard overkill—but that, of course, is just as I would have it.

This is a pre-order. Units ordered today will ship around Christmas.

Custom injection-molded, hand-polished switch plate

The most difficult part of making an HHKB housing is that, unlike all other Topre keyboards, its stock plate is integrated with its stock housing; they're a single piece of plastic. The HHKB switch plate thus can't simply be transplanted into one of my housings like the switch plate for others of my aftermarket housings.

This has meant my needing to re-create an entirely new plate from scratch with all the features of the original, minus the surrounding plastic housing. The only hitch is that the original part is one of the most intricate, fussy, hyper-engineered, and complex single-piece injection-molded parts I've ever seen. And when it comes to the feel of using a keyboard, my tests show that measurements off by even 0.1mm can perceptibly alter the feel and sound of a switch mechanism.

The geometry of my switch plates includes "slider housings" with mating surfaces that the HHKB sliders rub against during each keystroke. I have insisted that these be as smooth as physically possible to provide the optimal tactile and acoustic experience. In order to achieve this, I've had to work closely with the makers of the steel injection tooling (here in the USA) to create a special complex mold with 120 removable inserts that allow us to get deep inside the recesses of these slider housings to meticulously hand-polish each mating surface up to an uber-smooth mirror finish. Not only was this stupid expensive; developing this plate took literally years.

Each Heavy Grail comes with its own injection-molded plate in ABS resin.

Switch plates are available separately here.

Comprehensively engineered acoustic system

Each Heavy Grail comes with a gasket system die-cut from vibration-dampening Poron. This soft upper gasket forms a full seal around the switch plate, which helps to simulate that soft bouncy feel that is characteristic of the original HHKB's injection-molded housing and limits external sound transmission from the interior chamber of the housing.

External sound transmission and internal sound reflections are further mitigated by a natural merino wool felt dampener that rests on the rear cover plate.

Entirely made in the USA

The Heavy Grail is not only finished and assembled by skilled craftsman in America. Each part is made from scratch using domestic materials, right down to the the rubber bumpers, the aluminum in the housing, and the resin in the switch plate. Moreover, much of the work is done right here in California and neighboring states, reducing carbon emissions and allowing me to forge close personal relationships with the craftspeople who make my designs.

Complex compound geometry that can only be milled on a 5-axis mill

People who have followed the inspiration and philosophy behind my designs know that I'm particularly keen on midcentury-style retro-futurist shapes, and in particular housings that have my trademark taper along the side. However, combining that taper, a rounded edge, and an inherent slope angle means that the Heavy Grail can't be cut on a conventional 3-axis CNC mill. Instead, a much more costly milling machine (and and much more complex CAM program) must be used to for the process that carves the housing out of a solid block of metal. This roughly doubles the milling cost compared to a traditional 3-axis housing like the Norbaforce.

The Heavy Grail is milled in a high-tech Silicon Valley production facility that produces parts for NASA, Tesla, and Zeiss.

Customizable aesthetics

Material and finish options to suit your workspace and personal style.

K2 This minimalist textured white over machined aluminum pairs perfectly with anything. Option for a pink or white switch plate. Rear cover plate is texture white.

Aperture This unique metallic gray textured powder coat over machined aluminum is similar to the type used on some limited-edition Leica cameras and other high-end photography equipment. Comes with a black switch plate. Rear cover plate is texture black.

Sunset Blvd This matte (very faintly textured) pink over machined aluminum has a satisfyingly chalky pastel look. It is very challenging to apply and often requires multiple coats (hence its higher price), but the result is dreamy. Comes with a white switch plate. Rear cover plate is texture white.

Veracity Steel Hefty stainless steel meticulously hand-polished in the heart of Los Angeles by skilled metal artisans. (Like any hand-polished stainless piece, microscopic polishing lines and depressions will be visible up close at certain angles in bright light, but I work with a firm that gets the parts as close to a true mirror as humanly possible.) The Veracity option nearly doubles the weight of the Grail. Comes with a black switch plate. Rear cover plate is texture black.

Wide compatibility

The Heavy Grail comes in two different variants, the HHKB Pro 3 Classic series (the current, USB-C form sold by Topre/Fujitsu), and one version of the Grail that supports the HHKB Pro 2 (legacy, USB Mini) series. I'm phasing out Pro 2 support since Topre no longer makes that version, and only a few units in that variant remain. Note that the Pro 3 version of the Heavy Grail can also technically house a PCB from a "Pro 3 Hybrid" HHKB in addition to the "Classic" models, but with slightly reduced functionality (see next section below). 

Be sure to select the housing that correctly pairs with the HHKB model you own.


Thanks to the steel rear cover weight (even on models with an aluminum housing) and thick internal geometry, the powder coated Heavy Grails weigh in at around 3.3 pounds (1.5kg) when fully built, and the Veracity Steel at an astonishing >5.5 pounds (2.5kg).

Nota bene

This is a bespoke made-to-order product; patience is both required and cordially requested. 😊

Making a single Heavy Grail involves coordinating the work and different specialties of eleven (!) different factories and workshops, and there have been a lot of factory and supply chain disruptions in 2021 so far, so delivery could always take longer than anticipated. However, my hope and plan is to ship before the end of the year (for orders placed in or after May). The original group buy units (ordered before May) should ship before the end of the summer.

If you're nervous about placing an order for something you won't receive for months, check out the kind praise I've won from existing clients who have participated previously in similar group buys that I have run.

This kit for the ultimate HHKB build requires a bit of DIY assembly.

This is a kit for serious keyboard enthusiasts. While the build isn't difficult, it does require taking apart your HHKB and a bit of patience to transplant some parts from one plate into the other. I and others will be making build videos to help demonstrate the process by the time the group buy ships, and I'm always here by email, phone, or video call to help walk you through your build if you hit any snags.

Arcane technical notes

(Don't worry if you don't know what any of this means.)

Pro 2 USB Hub I've elected to block the USB hub on the back of the Pro 2 series. This better matches the new Pro 3 models and results in a cleaner look with better acoustic isolation.

Pro 3 Hybrid models If you venture to use a "Pro 3 Hybrid" model with a Heavy Grail, you'll lose the battery functionality, but the bluetooth should still work if you attach a powered USB cable. (The use case here is if you use your HHKB to switch typing inputs among multiple devices.) This isn't per se an offically supported scenario (the metal housing may interfere with the bluetooth range), but hobbyists who have experimented with this usage report that it's feasible. YMMV.

Use without gasket You can use the Grail without the isolation mount gasket, but your keycaps will sit slightly higher (just over 1mm) relative to the housing face. You can omit the lower gasket washers without any such effect.

Silencing rings If you use silencing rings with the Heavy Grail, your keycaps will sit slightly lower than normal (by the same amount as your rings are thick), unless you're using the purple sliders that have extended length to offset for silencing rings.

Dip switches The dip switches on on the Pro 3 model are accessible through the rear cover plate, as shown below. To access these Pro 2 switches, you will need to remove the plate.