Tom’s right, we only built 50 or 60 Katamacave’s in the mid 60’s. Slot bottoms were a fad at the time and I just shaped ours with a hump in the middle and harder edges near the rails, much like the Bonzers of the mid 70’s, but without the side fins. I think the slots made the boards hold the rail into the wave better but since, at the time we were using such large fins, the slots really were not necessary.
