Several years ago someone ordered a bunch of longboard blanks from China. They're fairly dense polyurethane foam and the quality control turned out to be impossibly poor. The guy sold them off on craigslist for $30 apiece, a price I hadn't see since the late 1960s. The quality was so poor that I had to sign a release such that no matter what, I couldn't return them. Nevertheless I bought three and used two.
The last blank is proposed to be a paipo or bellyboard, nominally 5' x 22" x 1.5" thick, maybe 2". I think that at 300 lbs I'll be able to duck dive this under whatever comes. Back in the day (I was lighter) I rode a 4'10" x 22" kneeboard with deep knee wells at various places on the North Shore. I enjoyed Pipe, Back Door, Sunset, Gas Chamber, Rocky Point, small Waimea and a few other places. I learned several things including that on large fast waves, kneeboards need smooth waves.
I'm wondering how to increase rocker in the remaining blank. I'll have to cut out the stiff 3/8" thick stringer. I envision something like thinner multiple wood stringers. Special ordering from US Blanks seems out of the question on a cost basis when I already have a blank for next to nothing and little to lose but my time. Have a nice bandsaw, planer, sander/polisher and surform, what could wrong? This ain't my first rodeo.
Sooo.... once the stringer is removed, how to increase rocker? I speculate that I'll skin the blank, shape to thickness, remove the stringer, cut the two pieces lengthwise into four and glue in new wood stringers of preferred rocker, in some sort of jig. I dunno how well three,1/8" stringers will hold increased rocker. If I can get it cut, glued and glassed, I figure (hope) the stringers will hold the increased rocker.
Ideas like these are the source of another thread about slab foam on Oahu. That thread isn't bringing useful results, so this is another approach.
Any better ideas 'bout the rocker?