Proposed design
A 110–130mm base disc carries 000–359° markings. A rotating overlay has a large wind arrow and windows or pointers for windward, leeward, 60° reach, 70° reach and gate-line bearings.
- High-contrast raised numerals every 10°
- Detents or friction washer that holds position in vibration
- Drain holes and rounded glove-safe edges
- Lanyard eye separated from the rotating centre
- Embossed TRUE / MAGNETIC reminder
Print specification
Use UV- and heat-resistant filament such as ASA or a suitable marine-grade alternative; avoid relying on PLA in a hot console. Use contrasting infill or paint for markings and stainless or polymer hardware compatible with salt water.
Validation
Test the printed scale against known bearings at every 10°, verify that no shrinkage distorts the centre, soak and drop-test it, and compare ten randomly selected outputs with an independent calculator. Mark each revision clearly.
Next step
The site can host an open STL and printable face template after a physical prototype has been checked. Any published file should include version, licence, print settings and a clear non-certified reference-tool warning.