Case & Spacer

The PolyKybd case and spacer can be 3D printed (resin SLA recommended) or CNC machined.

STL files

Part	File
Left case	case/case_polysplit72_left2_r4.stl
Right case	case/case_polysplit72_right2_r4.stl
Spacer (×2)	case/spacer.stl

All files are in the PolyKybd hardware repo.

The spacer keeps the right distance between the plate and the PCB and is printed twice (once per half):

Printing recommendations

Resin (SLA) printing gives the best results — the fine details of the case walls and display cutouts come out cleanly.

FDM printing is possible but the surface finish and dimensional accuracy are lower.

Tip

If your resin print has slight warping (common with large flat parts), use a hair dryer to gently warm the case, then press it flat under a heavy object for a few minutes. It reliably corrects minor deformations.

CNC machining

If you have the case CNC machined instead of printed, add threaded inserts to the four corner screw holes — the M3 screws need something to bite into since CNC aluminium won’t self-tap.

Screws and nuts

The current case revision (r4) uses:

• 8× M3×10 hex screws with rounded heads
• 8× M3 hex nuts (press-fit into the case corners)

Note

Older revisions (before r4) did not require nuts — the screws threaded directly into the resin.

Felt case (alternative)

A simpler felt case design is also available for a softer, quieter desk feel. See felt_case.jpg in the repo for reference.