Hi Bill, I have often wondered why there are not good slip (call them leeway) indicators on the market. They give information that is not unavailable from a GPS and a compass in practice. An inexpensive flux gate compass might be within 2 or 3 degrees - just no good at all for measuring leeway.
One tough part is keeping the vane perpendicular to the water. A pendulum seems like a good way, but then you have to damp the swing somehow (maybe use an Airpot?) AYRS once had plans for a leeway indicator but it mounted to the bottom of the hull, and did not remain vertical. Maybe there is an updated version. Now, if you could indicate apparent wind direction on the same display...
I really appreciate the technical portions of your posts. Thanks for taking the time.
