Welsford’s plan for the Navigator shows a rudder with an up-haul and a down-haul. I’m not too keen on the idea of down-hauls, as if I hit things and the down-haul doesn’t release, then bad things happen.
So I figured I’d omit the down-haul, and instead weight the rudder with lead, similarly to the centerboard. Hey, every little bit of tighting moment has to help some, right.
This time with the lead, I just went and bought a pile of lead flashing. I melted it in an old cast iron pan outside, and poured it into a mold made from steel and aluminium.
I cut that into the rudder core, made from four 12mm thick jarrah planks.
And then glued on cheeks made from Tassie Oak, roughing it to shape with the bandsaw, power plane, and jack plane, then 40 grit in the sander.
I’ve added a pivot point (16mm hole with 12.7mm bronze bushes), and an eye for the up-haul, which I think will have to be 2:1 on account of the weight.
Suzy, what was the weight of the added lead? 5 kilos?
Any idea of what the final weight of the rudder will be.
The lead is 3kg. The moveable portion of the rudder weighs 6.7kg at the moment, but it’s likely to come down another hundred grams or so as I continue to work on it.
The weight is about 45cm from the pivot, and the eye is only 15cm from the pivot, so there is about a 1:3 purchase inherent in the rudder assembly. Without a 2:1 on the uphaul, I reckon I’ll need about 12-15kg of force on the line to raise the rudder. The 2:1 halves that and should make it easy to lift.
Hi Suzy. So great to watch you build. There is another advantage to a weighted rudder, and that is that you don't have to remember to put it down. On my Navigator (and trailer) I think that my rudder would hit the ground going up and down a ramp. You'll have to keep an eye on that on the first launch. I can't believe that you're planning the next boat, but you're right. When you build a boat you find if you're more of a sailor or a builder.
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