tomodda wrote:Wow, those rudder cheeks are amazing
I'd be afraid of breakage, but you are apparently sailing along just fine!
I agree. The question is, whether the strength of the frame when twisted is as good as the full rudder head. It's not the same as loading this shape for bending as if it was a beam. I'm not a mechanical engineer so I don't know where to look for answers to that interesting question.
My rebuilt rudder blade is light enough that it has enough buoyancy to float a rudder head and tiller (if I grab the end of the tiller and stick the rudder blade in the water and keep it upright, it will float and not sink). So it does no longer add to the stern squatting, which is the primary concern. The other concern with extra weight, or actually mass at the transom is that it affects the angular momentum in pitching of the boat. It's normally best to concentrate all weight (mass) in the middle. Because it's mass that matters, buoyancy does not come into play.
The rudder blade looks like it's original, that means it's heavy.