I wander around the corner to the lumber yard in search of hydroskis, and tell them I'm looking for something to raise a twenty pound catamaran onto the plane at around ten knots. The store-hand points to uPVC skirting-boards: a chamfered 95mm type to accommodate drift. It should ideally be double-chamfered, and I suggest he mentions this to the manufacturers.
To attach it to the pontoons they have some 25mm angle too... happy days.
