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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