You can use a cheap trick Arne pointed out. The angle in the shaft creates a lever arm to automatically feather the blade correctly. If your shaft doesn't have an angle, you can easily make a right-angle handle at the end of the shaft (Arne calls it the "wrench") that gives you lever arm and performs the feathering function. The handle points "down" at right angle to the shaft when the blade is horizontal, or have the handle pointing up, Japanese style The length of the handle is the length of the short side of the triangle that would be created by your bent oar shaft (shaft as the hypotenuse). The lanyard is attached to the end of the wrench. Hope that makes sense, wish I had a photo for you. There's a small bit of discussion about the idea on a page about yrvind's yuloh 

Hi Yordon

A sculling yuloh needs a shallow bend in its shaft,  preferably just above the pivot point, so that it automatically changes angle at the start of each stroke (to give the correct angle of attack) Getting that bend exactly right is the difficult part of the challenge.

If the bend is too shallow the auto rotation is not enough to give sufficient angle of attack. If the bend is too deep the angle of attack will be so steep that the blade will be stalled.

When you get the bend right,  the attack angle will be right automatically - without you having to use your wrist muscles to twist the shaft at the end of each stroke . All you have top do is simply push/ pull the shaft from side to side.

Are windsurf masts pultruded fibreglass?  Would be very difficult to bend I'm sure.

I'm not sure if you could cut and shut the fibreglass using epoxy glue. If not you could make a welded metal sleeve  fitting to accept the cut ends of the fibreglass mast and create the bend that you need? Then you could keep on cutting and rewelding the metal until the bend is perfect for you.....

My present sculling yuloh is made from a stick that I found growing in the hedge which I judged to have just the right amount of natural bend. The blade part I made from an old pine bed that was given me and I glued and scarfed it together.  It took me a lot of attempts to get the geometry of the yuloh exactly right for me . There were a few that I made and eventually discarded because they were hard to use and awkward .

It's worth the effort to get it right eventually as when it works well the sculling is much easier . Less tiring and the boat goes faster..

Best

Jim

14ft Paradox 'Faith'

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