March 23, 2026
Description
Many door locks have oversized keyholes. Even with a key inserted, there is often enough clearance to see inside. Without a key, visibility is unrestricted. This is a direct privacy issue.
This is a minimal, gravity-operated keyhole cover designed to block line-of-sight through the door.
Automatically closes by gravity
No springs, no complex mechanisms
Low failure rate due to simplicity
Design Features
Asymmetric shape covers elongated/horizontal keyholes
Single screw pivot (standard hardware)
Thin profile to avoid interference with key insertion
Smooth rotation with sufficient overlap for full coverage
Designed for quick installation and removal
Printing
No supports required
Recommended: PETG or PLA
Layer height: 0.2 mm
Infill: 20–40%
Orientation: flat on bed
Assembly
Uses one small screw as pivot
Tighten until friction is low but stable
Ensure the cover falls closed under its own weight
Notes
This is a generic design. Adjust dimensions if your keyhole geometry differs.
Tolerances may vary depending on printer calibration.
Use Case
Apartment doors
Interior doors with visibility gaps
Temporary privacy upgrade without modifying the lock
License:
Creative Commons — Attribution — Share Alike
Sica
