Key model for the DM50

The keyboard design topic has been quite a headache, and it’s something that has kept me up at night.

There are mainly two keyboard alternatives: (1) keys that incorporate alternative functions on the key itself and have a certain angled inclination,

and (2) flat keys that have alternative functions printed on the faceplate outside of the key.

In terms of construction and design, flat keys are easier to make, but aesthetically, the keys with functions on the key itself are more appealing. Additionally, the angled nature of these keys provides a better tactile experience when using the calculator compared to flat keys.

Because of this, I’ve decided to go with the keys that incorporate alternative functions on the key itself. Although they are more complex to design, this isn’t a decisive factor. Painting the functions for the key finish will be necessary, but with the resolution of SLA 3D printers, and since the functions will be engraved, it will simply be a matter of filling the indentations with ink and cleaning them to achieve a professional result.

It’s worth noting that flat key designs are the most used in the industry (Texas Instruments, Casio, etc.). However, the latest HP Prime calculator has implemented keys with alternative functions, inheriting the design from calculators like the HP35S, HP16C, or even the HP 10bII+, all of which are more visually striking than flat keys.