Hi Waggy,
I've got some basic pics, but no full docu of the build.
It all started with a real basic rocker table (see pic). I cut out the top skin & the bottom skin, using 0.1" 3 layer ply. Cutting is carried out with a sharp knife. I cut out the side walls of the same 0.1" ply, that is 6 left side walls and 6 right side walls. Next, cut out the 6 nose and 6 tail pieces, made of the same 0.1" ply, all cut out with the knife.
NOTE: cut top and bottom sheet at least half an inch bigger than your shape. Same goes for the outer line of the side walls. The inner line is exactly measured, the outer line is bigger than the shape. When everything will be glued together, we take a jig saw and saw the real outline, that's why.
Now all the wood is pre cut, take a foam blank (I used a cheapo EPS (extruded polystyrol) from the hardware store) and shape it so that it fits inside the side walls. No need to shape the rocker, a straight blank will do, we'll bend it in shape on the rocker table. Try if all the pieces fit together nice and snug.
Now we want to glue stuff together. Important is the right glue. For woodwork, the best glue around is polyurethane wood glue like gorilla glue. This stuff produces a mild sort of foam and holds bomber, it's water resistant as well. Place the bottom sheet on the rocker table, fix it with some screws OUTSIDE the shape. Glue the side walls, front and rear pieces together, and the foam blank in the middle.
NOTE: PU glue allows you 1 hour to get your stuff in place, that's enough if everything is prep.
NOTE: side walls and front/rear piece must overlap by some amount. What I did was cutting every second side wall piece 0.5" shorter both front & rear. Front and rear pieces are big enough to cover up for this. If you don't overlap with every layer, it'll break at that point.
When everything is in place and glued (glue is still fresh), fix the whole thing to the rocker table by driving screws through the top sheet, side walls and bottom sheet into the rocker table. Screws are OUTSIDE the shape. Start on the rear end of the board and work symmetrically to the tip. 1 screw every 3", so you need maybe 100 screws. Once screwed down, weigh down the top sheet. Let glue set (1 day is safe).
Take screws out, and cut the outline of your board with a jig saw, working slowly and carefully.
NOTE: cutting slowly and carefully with the highest accuracy possible is really important, because sanding out any flaw takes eons.
Sand down to shape thoroughly, start with 40grid, down to 180 grid.
Do the layup. I did 1 x 4 Oz bottom, 2 x 4 Oz top epoxy job - read up board building on the web if you have never done a layup, i.e. here
http://www.surfersteve.com/I did bottom first with wrapped rails, then a top patch where you have your feet, plus the two top layers, not wrapped but hanging straight down. This creates a nice edge, once hardened out, you cut the overhanging top glass to level with the bottom, which leaves you enough resin to shape the rail that you want - I recommend sharp rails.
If you want fin(s), mount fin boxes / plugs as described above on the website.
You can of course do the same in polyester, or vacuum bag it, up to you. I will make myself a better rocker table and get a vacuum pump for future jobs, but as you see, you can do perfectly without.
Some pics:
That's really it. I did no paint job as I'm lazy, up to you.