Slightly modified oriolmachin's Keycap Case to fit on the 235 x 235 Ender 3 bed. It's a tight fit, but prints fine (I've done 6 trays and working on the cases now).

The cases you will need to rotate to an angle in your slicer. I've put a 3 tray and 4 tray version up. Both need to be rotated to suit.

Same settings as oriolmachin's case/trays.

Print Settings

Printer brand:

Creality

Printer:

Ender 3

Rafts:

No

Supports:

No

Resolution:

0.28

Infill:

0

Filament brand:

eSun

Filament color:

Black

Filament material:

PLA+

Notes:

Using a skirt on a PEI bed, although the skirt is probably not needed for this size.