I’ve designed this modular perpetual calendar that you can fully adapt to your needs. Thanks to its spring-loaded system and interchangeable tiles, it works perfectly as a standard calendar, a reminder board, or even a score tracker for your own tabletop games.

Design Features:

4-Slot Spring System: Easily display tiles for numbers, months, years, or custom icons.

Modular & Versatile: Ideal as a desk organizer or a functional component for custom-made games.

Customizable Tiles: I’ve included tiles with numbers, months, and years, plus blank tiles so you can create your own designs.

Reinforced Body: The frame features pockets for M3 heat-set inserts (5.7mm length), ensuring a solid, durable, and professional assembly.

Technical Details & Assembly:

Hardware: The back cover is compatible with M3 screws (8mm length), whether round or flat head.

Alignment: The cover includes a guide notch that must be oriented toward the bottom of the calendar for a perfect fit.

Spring Mechanism: Optimized for 25mm long springs with a 3mm inner diameter (recommended spring rate: 3.41 LBF/IN). However, the system is flexible, allowing you to swap springs to adjust the tactile pressure to your liking.

How it Works:

Operation is very intuitive: simply insert the tiles through the side slots to fill the 4 calendar spaces. To store or rotate tiles without losing them, you can reinsert them through the top and bottom holes.

Additional Notes:

• Custom Tension: You can adjust the spring length depending on how many tiles you want to load in each slot to achieve your preferred tension.
• Assembly Aid (Optional): I’ve included a mounting jig available for download. It’s designed to help you align and press the heat-set inserts more accurately and easily.

This calendar is designed to perfectly match my Retro-Style Clock, which you can find here: 

Assembly Video: 

Usage Video: