Mister Vee self steering systems

Use of Mister Vee Y&B Standard on a trimaran

Windvane self steering can not cope with constant acceleration followed by slowing down. This means that it may not be possible to steer an ultra light displacement boat or multi hull.
A windvane self steering system uses the apparent wind direction to keep on course.
When the boat accelerates, the direction changes. The system will correct accordingly which will in the end make the boat slow down.
The course will again be corrected and the cycle starts again.

will it steer my coco minitransat

Ultra light displacement boats like Mini Transats generally are too fast to be steered by a windvane self steering system.

The boats apparent wind is cause by the boats speed as well as the true wind direction, and that makes course keeping unreliable, often resulting is big variations in course and continuous speed changes.

Will it steer my bigger boat

The power a windvane self steering system can deliver is directly related to the size of the pendulum blade, and the height above the water. The higher the mounting, the longer the pendulum rudder, the higher the force the system can generate.

But the the actual force depends on how light the boats steering actually is. An un-balanced barn door rudder will require more force to steer the boat than a fully balanced spade rudder. The lightness of the transmission in the rudder system is also a factor.

Which product to choose

From pictures available on the internet it seems that most cal 25s have an outboard engine in a cut-out in the transom.

That allow for the use of a standard length outboard engine which would leave too little space for any windvane self steering system, including Mr. Vane.

Mr. Vane was designed to be used in combination with a centrally mounted outboard engine on a lifting outboard bracket.
This generally requires a long tail or extra long tail outboard engine.

What is the diffrence between Mister Vee Y&B and Mr. Vane?

Generally speaking, Mr. Vane is intended for smaller boats, and Y&B is intended for any size up to 12 meters. Other sizes of boats may work too but hey, this is a general answer.

The other mayor difference is in the mounting options.
Y&B standard offers an integrated solution for the vast majority of boats, and the flat configuration of Mr. Vane ads some options for even more situations, primarily on smaller boats.

For the best comparison, please refer to the Mister Vee Product Brochure from the download section.

Mr. Vane or Y&B ?

For a boat with a transom hung rudder I recommend Y&B standard with an extra mounting tube.
This system has a mounting kit included that together with the extra mounting tube allows for mounting around and behind the rudder.

For fitting to smaller boats Y&B can be ordered with a short pendulum rudder, which is a free option.