Chai45G, a homebrew keyboard with a trackball in the center of the Grin array


On March 9, 2024, Mr. Gohanda presented a new Chai45G prototype.

The Chai45G is an all-in-one device with a 40% layout that uses the Grin layout invented by Mr. Policium and a 25mm trackball in the center of the keyboard.

The first appearance will be in January 2024.

It appears to have been developed in only 3 months, starting at the end of December 2023.

The series of production process is also introduced in the following post.

The prototype is priced at 20,500 yen (including tax) for matte black and 19,500 yen (including tax) for matte white, and soldering service is available if soldering is difficult.

Build guide is here ▷▷▷.

The RP2040 is surface-mounted, so no ProMicro is required, all keys are hot-swappable, and an acrylic laminate case is included.

The mounting system is the Tadpole mount used by Bully and others, so a soft keystroke feel can be expected.

The ball case 3D data and acrylic case data will be made available to purchasers, who will be able to order their own cases in their favorite colors after purchase.

If you are interested, why not tap the “Suki” button on the Booth page?

BOOTH sales page is here ▷▷▷.

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河村 亮介のアバター 河村 亮介 GreenKeys運営責任者/事業代表

WEBサイト運営事業GreenEchoes Studio代表をしています。他社法人メディアの運営ほかキーボードメディアや通信系メディアへの寄稿を行うなど、ウェブライターとしても活動しています。今年はオリジナルキーキャップセットを作る予定。