The deck of a setka is supposed to be slightly curved so the 5 beams supporting it must be curved. I could probably have cut out the slightly curved beams from solid boards like many others have done but since I wanted to play with other building methods I chose to laminate them on a template. I ripped 8-9mm thick strips with a circular saw and prepared the surfaces for gluing (planed and sanded with 80 grit):
For the template I used the leftovers from cutting the transom beam, below a picture from a trial run to see how rigid the template needs to be to give me the correct shape. The beams consist of 6 to 7 strips (7 strips for the beams that are part of a frame, 6 for the ones that are in between) which makes sure there is not too much springback after gluing (which btw is accounted for in the shape of the template). The amount of springback is approx. S/N^2 with S the sagitta of the arc and N number of laminations. The formula works well enough it seems, the shapes came out perfect.
Gluing the whole thing together with slightly thickened epoxy (and not too much clamping pressure to keep the epoxy inside the joint):
The resulting beams look quite nice:
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