Thanks to all you fine folks who answered my first posting, I completed conversion of the Figment from tiller to wheel today. I incorporated a LOT of your ideas. Also had to do a bit of innovating, since the builder had modified the stern by removing the vertical sternpost and replacing it with a 2x6 bolted flat to the stern. So I modified the plans by making a rudder box that slants to follow the sloping stern, but with a blade that is "bent" to point straight down. It is also a kick-up, loaded with a bungee so as to lift up if it hits something solid, rather than just tearing the stern off, as the old one would have (anyone wanting a FREE used rigid rudder, all fir and heavy as lead, just contact me and pay the freight!).
As usual, I overbuilt... the box is glued, screwed, through-bolted in three places and a bit more robust than plans call for. The rudder blade pivots on a half-inch stainless bolt, running in bronze bushings glued through the wood. Since the rudder box swings on an inclined axis rather than a vertical one, this would cause the end of the stub tiller to move in an up-and-down arc as it was moved across, so the stub tiller also had to be made to pivot to keep it level. So I mounted it on a single 3/8 stainless bolt, also running in bronze bushings.
The wheel itself is one of those purty little jobs from eBay (I can't make a really nice one with my simple tools), mounted on a 3/4-inch shaft (bronze bushings naturally) and I stretched a section of bicycle innertube over the steel shaft to give solid purchase to two or three turns of the rudder rope.
I didn't have to cut any more lazarette holes, as I had feared... but I think I did develop several new joints in my arms while working through the original lazarette, repeatedly shortening the (pre-stretched) rope and tinkering with the turnbuckle.
At any rate, the whole shebang works like a charm... the wheel makes three turns from stop to stop, which is about what I wanted... and it's all thanks to your helpful advice. Good show, all!
Walt
Weekender Figment :wink: