Introduction to GRIN One

GRIN One is a 65% mechanical ergonomic keyboard that combines superior design with innovative functionality, bringing a new fascination to the world of key typing. Its sleek design and comfortable key feel make it the ideal choice for users seeking style and performance.

GRIN layout

The GRIN One uses the GRIN layout, a special key layout that differs from common keyboards. This layout is ergonomic, with curved lines that take into account the natural movement of the fingers, but is based on the common low-staggered layout, so there is no difficulty in learning it despite its unique layout. This ensures a smoother and quicker typing experience.

Case Designs

The GRIN One case is elegantly designed with the curves of the GRIN layout. The materials used are carefully selected, with the MJF 3D printed PA12 (nylon 12) case section as the basis, while the bumper and bottom plate are available in metal (copper, brass or stainless steel) or acrylic plate.

The metal plate increases weight and rigidity, eliminating the instability often found in 3D printed cases and giving a more stable feel. The copper plate version has a total weight of 1.5 kg. The high-end design, which uses different materials and emphasises curves.

Mounting method

The GRIN One not only looks good, but also functions well as a keyboard. It uses a unique gasket leaf spring mounting system. This is an improved version of the existing system with a softness adjustment function.

The leaf spring mount system is a method of connecting the PCB to the case via a plate spring to achieve a softer keystroke feel. Compared to gasket mounts, it can be softer by design, but the following points should be noted.

Leaf spring mount improvements:

1.The springs in the keyboard are prone to vibration

Vibrations lead to noisy sounds and increase discomfort when bottoming out.
⇒Poron gaskets were used to dampen vibrations caused by the springs.

2.Too soft, difficult to get a typing rhythm

A moderate bottoming feel helps to maintain the rhythm of typing, but too soft and you lose the rhythm. Unfortunately, everyone has a different preference for keyboard softness.
⇒While leaf springs are used, a softness adjustment function is provided to meet a wide range of needs. Details are given below.

3.different softness depending on the keystroke position

Due to the construction of the leaf spring mount, which is spring-supported on the periphery, the softness is not constant depending on the striking position. Relatively, the periphery is softer and the centre is harder.
⇒Based on FEA analysis, appropriate slits are provided on the PCB and switch plate to ensure a constant feel regardless of the keystroke position. In addition, a flexible PCB with a thickness of 1.2 mm is used to facilitate the effect of the slits.

Softness adjustment function

As shown in the diagram, the PCB with the switch attached is held in the upper case (black part) via a Poron gasket. On the other hand, the PCB is attached to the case via a leaf spring and the mounting part can be changed in mounting height with washers and screws.

Soft setting

Hard setting

In the hardest setting, as can be seen in the diagram, the mounting point is high, but the PCB is held in the upper case and the leaf spring is always subjected to an upward force. In the hardest setting, this upward force pushes back the impact of the keystroke, resulting in a harder feel; GRIN One can be easily adjusted to four different hardness levels by changing the position of the washers, without having to replace the plate.

Price

Main Kit

Copper plate (sandblasted + clear paint) kit - JPY37,000 (worth USD265)
Brass plate (sandblasted + clear paint) kit - JPY37,000 (worth $265)
Stainless steel plate (shiny) kit - JPY37,000 (worth $265)
Acrylic plate (red/green/blue) kit - JPY29,000 (worth $210)

Product variations are bottom plate and bumper plate types.

Option Kit

Mod Kit - JPY1,500 (worth $11)
Solenoid Kit - JPY2,300 (worth $16.5)

Main kit includes

• Pre-soldered PCB (including XIAO RP2040 and Cherry MX compatible sockets)

• FR-4 switch plate

• Upper case (3D printed)

• Bottom case (3D printed)

• Top plate (matt black acrylic)

• Bumper plate (copper, brass, stainless steel, acrylic)

• Bottom plate (copper, brass, stainless steel, acrylic)

• Poron gasket foam

• Screws

• Washers

• Stabilizer spacer (for 1.6mm stabilizer)

Mod kit includes

• Switch Foam (Poron)

• 3U stabilizer wire

• Deadening tape (aluminum, butyl rubber)

• Tape for flex-cut

Solenoid kit includes

• PCB

• Solenoid

• Transistor

• MOSFET

• Resistor

• Diode

• 2P Connector

• 3P Connector

• Cable

• Screws

Soldering is required

Sales method

The product is made to order with a set shipping time. Please expect approximately two months from order receipt to shipment. Please check the expected shipment at the time of purchase as it will be stated on the product page. Small specification changes may be implemented without notice depending on the production time.

Sales website

International sales website
https://grin-keebs-intl.stores.jp/

Schedule

Early May: Production of final review version
→ production has started sequentially from 22 May
Late May: Call for a few reviewers* Shipment mid-July
→ now
Late July: Order start shipment lead time is around 2 months.

And more...

More hidden GRIN One features will be revealed in the future.

Special thanks 私の相談相手の方々
Video & Support by Keeb Taro.
Photo by imrogfada.