CardKB2 -- Modular Case

This CardKB2 case follows the guiding principles of my original CardKB case design. The main difference is that the ball-spring mechanism is flipped -- the springs are now printed with the case itself. The new keyboard uses better keys so we didn't need to compensate for "click-feel".

• All ports and buttons are accessible.

• Buttons are easy to press and kind of ergonomic for the size.

• Funky slots on top let you see the PCB and dissipate heat from the MCU.

• ~6.5mm thick (excluding keycaps) encasing the PCB.

• ~9mm with the keys.

• If you modify the key mapping you only need to apply your new label in the STEP file (in a CAD)

• Keycaps were inspired by the HP-27S series calculators. The proportions had to be changed for printability.

Assembly

• Print Key Case.step

• Use M2/BT2 screws to screw the CardKB2 module to the Key Case.step

• Print keycap row-1234, row-asdf etc, ensuring the orientation is set with slanted face is on the bed.

• A slight twisting motion easily removes the keycaps from the build plate -- but just be gentle with the pins on the back.

• Insert firmly the key cap.

Disassembly

• To remove the keycaps tilt them upwards aligned to the springs then pull them out with a sideway motion.

Print Notes

• 0.2mm nozzle works really well on the keycaps, which are now printed flat -- the "ball" prints at an optimal angle, making the keys strong enough to be inserted/removed several times.

• Print all files facing down.

• All files are printable with 0.4mm nozzle with minor loss in quality compared to 0.2mm.

• The STEP files provided for the keycaps are for each row and contain the labels in a separate single layer.

  • Auto orient the top of the keys to be on the bed.

  • Change the filament for this compound shape to change the label color, and paint specific labels if you wish.

  • Ensure "only one line on first layer" is checked.

  • For a single color print you may set the compound shape as a negative modifier.

• The Case itself is optimized well for 0.4mm nozzle and so no special considerations. You could prefer PETG, but my tests were all in PLA.

  • You can use a lighter filament for the diffuser sub component to be able to see the light.

Included Files:

• KeyCase.step

• row-{switch row+label}.step

• cardkb2-keys: BambuLab 3mf

• kb2-keys.svg: If you need to change the labels, this is the reference SVG file (two versions: text preserved vs outlined). You may need to rescale the SVG when importing in CAD.

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