I've perused the 'show your hull' thread, followed the links, and read everything I could find. So I'm closing in on finalizing the design of my next board, a 7'6" rounded pin hybrid type board. Here's what I have so far. Please look at my sketches, and give me any imput you'd care too. I'm unfamiliar with hull displacement boards, and am anxious to try the design on my next board. I'm an old codger, getting back into surfing after a 23 yr. layoff, so I'm back to being an intermediate beginner at best. I like carving turns but no vertical surfing, probably ride this further back and turn rather than further forward and trim. 5'7" 165 lbs. This board is for So. Cal. point break surf.
The board will be a hollow wooden surfboard, but that shouldn't matter much at this point I'm just working out the shape. 7' 6" long, 22" wide, 2 3/4" thick, 4.5" rocker in the nose, 2" in the tail, small flat rocker section in the middle. Widest point at 39" back. 18" wide nose, 16" wide tail. Rounded pin. Single or tri-fin (probably fcs or other). Displacement hull shape with thin rails, v in the tail going to completely flat behind the fin, with hard down rails in the very back. Crowned deck to keep thickness in the middle.
I'm open to any suggestions from those more knowledgeable. I've just put this design together from picking the brains of others. Thanks for all the help from the Swaylocks crowd!
More hull in the nose, zero in the tail, like flat and lose the tail rocker...
imo....
[/quote]
Thanks for responding! I will definitely re-do the design with more hull in the nose, less in the tail. The reason I added some V ahead of the fin is that Paul Gross recommended it in this article http://www.swaylocks.com/resources/detail_page.cgi?ID=456
He said "If you want to use V, go up to 15.5" or even 16" (tail width). Keep the V ahead of the fin. V behind the fin adds too much rocker to the rail line in the back. No drive. V in front of the fin flattens the middle rail rocker line, making the board fly out of turns. However, V kills the forward trim capability of hulls. Turns the board into more of a tail rider. Personal taste determines which is better.
"6'8" to 7'8" is a comfortable length range, but not limited to that. 3" is a safe thickness, but you have to use a triplane or domed deck to keep the rails thin enough. Resist the temptation to go thinner with a flat deck. The bouyancy of the center area is what get these boards rolling in smaller conditions. If you want thinness, put it in the rails and tail. And keep the rails at least 60/40 or higher until the last 24" to 18". Rocker low...4-5" in the nose. 1-2" in the tail. A slight straight spot running through the middle. Avoid evenly curved rocker schemes."
So, based on that, I added some V to the tail. If in your experience a flat bottom is better, I'll go with the flat tail, since I have no experience with these at all. And I'll reduce the rocker in the tail also.
PG is a master of the hull shapes, he explains the V forward of the fin makes the board ride from the tail a bit more. I ride my hull from the middle or front third for the trim, speed and glide.
What he suggests makes sense but I am after the trim and glide.
