Shaping bay chronicles, what is this you may ask, well its a blog post series documenting new prototype stuff i'm working on in the shaping bay, a few photos with some theory and ideas all put into practice..
so here we are at Vol.1, the first edition.. which also coincides with an interesting board i shaped at the end of the year, (subsequently spurring on this very blog post). the displacement hull, something i've dabbled with (vee bottom middy and smooth mover models both have convex bottoms) but a world i've never fully submerged myself in, a lot of my shapes utilise vee and belly but nothing quite like a proper displacement hull does, so here is my first go at a displacement hull.. this particular one will be for me, i've designed it with a particular cobblestone point break in mind but also for some beach break action also..
What is a displacement hull? well my understanding is: the convex (opposite of concave) bottom shape pushes water onto the rails rather than focusing it down the center, its an idea that stems from boat design the ideology being that the convex bottom works by having the apex of the bottom shape within the water this creates a large surface area in the water which will ulitize a weaker (slower) power source with more efficiency, rather than a faster concave that skims on top of the water surface.
what makes a displacement hull? well i've done my research on this, and from what i understand from the ones i've looked at in the flesh their highly refined and there is a close line between magic and 'dog' - the main criteria is obviously the belly bottom shape, specifically in the mid section with the nose and tail being rolled but a bit flatter, ideally the deck and the bottom kinda match each other in terms of roll, this makes a thin knifey foiled out rail.. due to the low volume rail some center thickness is good and a stubby outline works best for maximising surface area on water flow, fin box is pushed far up and a reduced base flex fin is optimum for performance, hard edge in tail just as critical and s-deck optional, favoured by some shapers loathed by others.
So for my displacement hull, i settled with 6'8, i wanted to go longer BUT i only had a 7'4SP blank going spare and 6'7 was as long as i could go with the desired rocker i had in mind (sub 3 1/4" nose ((quite flat nose)) and sub 1 1/4" tail rocker ((flat tail)), template wise, i used my vee bottom middy #T3 for the mid sections (12" up from tail - 12" back from nose, and then weirdly my smooth mover (which is almost a displacement hull but not quite) template worked perfectly on the nose and tail, i set up my mid point +5 inches forward and pulled in the tail template behind where i want the fin to go. after cutting the outline i set up the bottom and deck shape due to the extreme roll in both the top and bottom the rails set themselves up and just needed rounding out, i kept a hard edge in the tail but a softer rail up front and almost a little turned up in the very front, all this blended in with a slight but subtle S-Deck, the thing that really tripped me out was how there's not a flat spot on it, curves everywhere... anyhow im hoping it will be run thru the factory early January and ready for testing soon after.. if anyone is interested in having a go, give me a shout.. the more feedback the better.