¶ How
How do you use a 40% keyboard?
To an outsider, 40% keyboards may look like just novelties. Numbers and symbols like $ are commonly typed and useful in a variety of situations. Most 40% keyboards lack things like a dedicated numrow and are often smaller than just a 60% with its numrow cut off, so how do people actually use 40% keyboards?
The key to the functionality of 40% keyboards and how the people that use them get work done while using them lies in some key features of QMK firmware, which is the firmware most custom keyboards utilize. QMK allows a variety of complex actions to be carried out on keyboards aside from only macros. The QMK functionality that enables 40% keyboards to function just as a full keyboard would are as follows:
- Layers
- Tap Dance
- Combos
To have access to them, a lot of 40% keyboards use Vial-compatible firmware. Vial is a graphical interface for a lot of QMK features that allows you to set up those mechanics to match your needs.
¶ Layers
Layers are probably the easiest to understand as many people who use keyboards larger than 40% also use layers. Using shift is technically using a layer. Shift changes the keymap you type on so that instead of typing a lower case letter you type a captial letter or a symbol instead of a number. Caps lock in this case essentially functions as a toggle for layers rather than a momentary switch like shift.
40% users will often have more than two layers on a keyboard, depending on what they use the keyboard for. The base layer (layer 0) is most commonly where all of the alphabetic keys are. Often—but not always—numbers will reside on the second layer.
¶ Tap Dance
The tap dance funcitonality in QMK allows a key to act differently if it has been tapped once, double tapped, or held down within a certain user defined time span of pressing the same key again. Tap dance is especially useful on smaller 40% layouts or sub-40% layouts. In cases where a user is using a keyboard like a QAZ where there are not dedicated keys for mods, tap dance can be utilized to make keys function both as mods and as alphabetic keys.
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| QAZ keyboard with DSS Micro keycaps. Photo by BrokenFlows#1024 on Discord |
¶ Combos
Combos are another way of making keys act as other keys. Combos would be used in circumstances that would make using layers or tap dance confusing or incovenient. Using a combo can allow for repeated keystrokes without misinput.
A common use for a combo would be backspace on a QAZ. Using tap dance or layering on the P key (the topmost rightmost key) as backspace would be slower than using a combo of O+P and less accurate. The O+P combo can be repeated as quickly as both keys can be pressed and unpressed.
¶ Example keymaps
Finding a perfect keymap for your needs is an iterative process which may take a lot of time. You can find examples of 40% keymaps in #keymaps channel of 40% Keyboards Discord server or on the KeymapDB website.
¶ QAZ
QAZ keymap with 3 layers, which uses tap dance for Shift and layers, and combos for Backspace, Tab and Esc.
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Numbers layer is activated by holding the bottom right key. Shift is activated by holding z or . keys. Esc, Backspace and Tab are invoked by pressing Q+W, O+P and A+S |
¶ Minivan
Minivan keymap (one of the most standardized 40% keyboards). The Minivan, originally by created by a user known as Trashman, is essentially the bog-standard 60% of the 40% keyboard community; it is the keyboard a lot of 40% beginners start with.
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| This is just one example of a Minivan keymap. Minivan keymaps can vary siginificantly |