A model was made in SketchUp:
The hardware I selected rabbeted the rudder gudgeons and employed cherry wedges to align a 5/16" rod through stem gudgeons.
This allowed for precise location of rabbets needed in cheeks which were routed with a clamped fence.
|router/fence set up.|
|Stop block to left.|
|Finished routed fit.|
|Single cheek and gudgeons.|
|Rudder head clamp up. Rod positioned for square alignment.|
For the tiller arm a 5 degree "advance" was given to the arm instead of making it perpendicular to the rudder. Made of white oak, it is some hard stuff to cut, rasp, plane and file. This was really my first use of the spokeshave which proved a fun tool for sculpting the underside of the arm.
|Rudder mortise and arm tenon.|
|Arm fitted after much filing.|
A mortise in the tiller arm accommodates a wedge of cherry. This is an amazingly tight combination. The wedge has a hole for securing with line and I exaggerated the head for easier removal.
|Wedge and sheave holes.|
|Tiller arm sweep.|
Next? I'm thinking mast steps and breasthooks.