A Photo & Discussion Forum for Wharram Design Enthusiasts
Here's an old photo of Vaea's aft end that shows the starboard tiller fairly well:
As I recall from the plans, when building these tillers, you hang weights(or some other method) on the crossbar end until you obtain the proper amount of deflection, and then you let the epoxy set.
Thanks for the ideas to everyone. Pardon the 2 year delay in reply. Sincerely, Mark Hamill
kim whitmyre said:
This info is from a fellow named Tom Speer on BoatDesign.Net:
"The easiest way to achieve it is to use tillers to control the two rudders, linked together with a bar connecting the ends of the tillers. If you angle the tillers toward the centerline, the inside rudder will be turned more than the outside rudder.
How much to angle the tillers depends on what you are trying to achieve. The tighter the turning radius, the more Ackermann angle to use. As a quick approximation, draw lines perpendicular to the keels/boards at their center of lateral resistance (say, the quarter chord) and perpendicular to the plane of each rudder and board. You want all three lines to meet at the center of the turning radius. This sets the amount of differential deflection of the rudders. " Speer says between 10 to 15 degrees is typical.