A technical comparison of all the major systems

We put together the following tables (taken from the book Selfsteering under Sail) to give you an overview of all the windvane steering systems that have ever made it into serious production and to help you compare those that are still on the market today.

The first table includes all the different systems that are or have been generally available for purchase and indicates the type, mode of operation and power leverage of each model.

Summary of the 12 types of system

Windvane type

The vertical or V vane pivots about a vertical axis. Originally horizontal or H vanes pivoted about a strictly horizontal axis, but almost all now have the axis of rotation angled 20 degrees back from horizontal. It is useful if the windvane can be rotated fore and aft in its clamp in response to changes in conditions. A more upright position gives maximum sensitivity for light air sailing, while damping can be optimised in stronger winds by angling the vane back.

Servo power

Servo-assisted systems generate greater steering force

Power leverage

This is a measure of the potential power of a system. The longer the lever, the greater the steering force generated.

Bevel gear

Any system with a bevel gear linkage has automatic yaw damping - oversteering is impossible!

Boat size

Please refer to manufacturer specifications

Technical data of selected windvane steering systems I

Materials

We recommend:
- plywood windvanes, since every sailor must be at least somewhat competent with a fret saw
- aluminium castings, as they are light, need little care and can be machined with great accuracy
- buoyant rudder blades, as buoyancy reduces bearing friction

Bearings

We recommend:
- PTFE/Teflon sliding bearings, because they do not seize even after prolonged use

Types of yaw damping

We refer to any solution based on a 2:1 bevel gear linkage as automatic damping. Some systems have manual damping, where the user manually changes the transmission ratio in response to changes in conditions.

Weight

The less weight you have in the ends, the better your boat will sail.

Technical data of selected windvane steering systems II

Remote control

is best realized using an infinitely adjustable worm gear. The ability to make small and precise course adjustments is essential for good upwind performance. Any system that limits you to large, multiple degree increments will cost you pointing and distance.

What to do with an idle pendulum rudder

The best way to keep a pendulum rudder out of the way when not in use is to lift it up out of the water to one side. All you have to do then to set it back to work is let it swing back down into the water.

Emergency rudder?

As far as we are concerned the only types of windvane gear that can function effectively as an emergency rudder are the auxiliary and double rudder systems. A pendulum rudder is simply too small, too lightly built and too awkwardly fitted to provide anything approaching useful steerage in conditions severe enough to disable the main rudder.

Removable self-steering

You may find it wise in a crowded marina to remove your windvane gear in order to avoid potential collision damage. The easier your system is to remove, the more likely you are to feel comfortable doing this. A readily removable system is also an advantage at the end of a long passage when you need to put the dinghy back in the davits.. 

How many mounting bolts?

Drilling holes in a boat is bad news - the fewer bolts the better!

Wheel adaptor

We believe the best type of wheel adaptor is a two-part assembly based on the principle of the disk brake. This design provides easy course adjustment and trimming, optimal overload protection (provided the clamps are not overtightened, the drum that receives the transmission lines from the vanegear will slide on the disk in a sudden gust and protect the rest of the system) and the ability to revert to manual steering all but instantly.

Available sizes

All systems offer different shaft length options and some also have different rudder blade sizes.

Technical data of selected windvane steering systems III