Kayak Forum stressed I try oodles of yaks before I invested too much time building something that eventually didn't suit me. True words which I am grateful for.

The foam is just used to make the form. It'll be pitched once the reverse mold is made. Unlike surfboards skis are hollow. I agree it might get expensive but then so are cedar boards. As for mass production quality using the created form. The same could be said of the strongback with the plywood sections. This too could be used to make multiple yaks.

There is beauty in both avenues.