If an increase in a boards thickness didnt equate with additional buoyancy and weight, would that influence your shapes?
This is a provocative question… If more material doesn’t increase weight or buoyancy (a seeming contradiction) then I assume that removing material wouldn’t have an effect either. Then I could make a board as small as I wanted and it would still float me just fine… This matters when you’re 230 pounds. Damn few boards will afford sufficient float to effectively compete for waves in crowds of kids on six footers, who only weigh 120 to 140.
Imagine if you could… Make a 2" thick, 10 longboard that weighed 6 pounds. Make a 4" thick 6 shortboard that didnt ride like a cork. A boards rails and foil could be designed with as much, or as little, wave surface penetration as necessary, without any compromises in buoyancy.
Thickness also equates to strength. Surfboard strength is strongly dependent on board thickness. If you make a board thinner and more buoyant, but use normal glass/resin, it will snap a lot easier. I get boards thicker than normal specifically to avoid snappage, a significant problem for me.
—If you make a board thinner and more buoyant, but use normal glass/resin, it will snap a lot easier— Unless you don’t use fiberglass and resin. Then you can keep free thinking. Dreaming on, Rob Olliges
Allow me to re-phrase my question… (I was hoping for a bit of theoretical discussion about foil and rail thickness, apart from other aspects of design) “If an increase in a boards thickness didnt equate with additional buoyancy, weight, and changes in strength, would that influence your shapes?”
With floatation out of the picture, a high performance rail could be no thicker than 1/4 inch; hypersensative, fast, maybe too fast. Board about 4’ to 5’ long, parallel outline, 16-17 inches wide, fish tail with small fins on the rails. Add some volume and soften the edge to the area in front of your front foot to provide some forgiveness on turns. 4 inches of rocker in the nose and dead flat everywhere else (no need for concaves to provide lift). Essentially, a long paipo. Contoured, rail to rail flex (Velo flex) in the rear third, and rocker flex from the tips of the pins to the “butt crack”. (easy to experiment/control flex with movable stiffening beams) Most current surf spots would become too slow to have fun… Desensatize your board by adding length and volume to the rail. Smaller waves, increase width for planing.
What Lee is describing sounds like my impression of a tow-in board. Haven’t seen one in person yet. Did see a (supposed) fish yesterday that was probably the thinnest potato chip board I’ve ever seen…doubt that would float my dog. Looked fast and mean though, perfect for these times.
which doesn’t rely on paddling at all, it’s fully a high speed planing hull. You’d have to be careful about the flex characteristic and not compare too much to Greenough’s flexy flyers, because stand-up your weight is delivered to the hull differently than on a kneeboard where your legs from knee to toe are in contact. Stand-up, you’d need a stiff area to stand on. On a board only four feet long, tou’d only need enough rocker not to catch the nose in chop. However, you couldn’t surf such a tiny board in mushy waves, or you’d not have sufficient speed or area to generate lift, a problem a weighty guy like me is well familiar with. The probably hypersensitivity of the board, and requirement to operate at full planing speed, decreases the importance of rail shape - the wetted surface of the hull is bounded by edge.
If a board’s thickness doesn’t equate to strength against snappage, you are violating physical laws. A board’s strength comes from the glass and resin. This is strongly impacted by thickness. The role of the core is giving a shape to the glass. There is no getting around this. To make a board thinner, you either use a lot more glass, or you have a weaker board. There was an article in the last Surfing about different cores. One board was a thinner board, made from S-core. It snapped in testing. That was no accident (even though it snapped at Teahupoo). The article stressed how the lighter core allowed more buoyancy per volume, and the end result was snappage - which was largely ignored. Dreaming and free thinking is cool. Engineering is about not losing sight of tradeoffs in the process. No matter what, you gotta design boards with reasonable strength against snappage. And, board thickness relates very closely to strength against snappage. I’ve been thinking a lot about this, as I snapped 4 boards last year, and I don’t get them for free.
I’m pretty sold on fuller rails just because they seem to dig less on the slopey sometimes mushy waves I ride in normal conditions around here. After riding many boards (short and long) I really like the projection I get from dome decks and fuller rails. My take on boards like edge boards and the old Shoe by Con is that the flutes along the rails (topside for the Shoe, bottomside on the Wilderness) allows a thicker board (for paddling) with thinner rails for sensitivity on steeper faster waves yet the slot effect along the edge prevents digging… maybe the best of both worlds? http://www.larryobrien.com/twoshoe.htm
“With floatation out of the picture, a high performance rail could be no thicker than 1/4 inch; hypersensative, fast, maybe too fast. Board about 4’ to 5’ long, parallel outline, 16-17 inches wide, fish tail with small fins on the rails. Add some volume and soften the edge to the area in front of your front foot to provide some forgiveness on turns. 4 inches of rocker in the nose and dead flat everywhere else (no need for concaves to provide lift). Essentially, a long paipo. Contoured, rail to rail flex (Velo flex) in the rear third, and rocker flex from the tips of the pins to the “butt crack”. (easy to experiment/control flex with movable stiffening beams) Most current surf spots would become too slow to have fun… Desensatize your board by adding length and volume to the rail. Smaller waves, increase width for planing.” ------ Lee, Here`re some tasty designs to chew on, with a distinct carbon graphite flavor… 
if i could get a board that was 2.5 thick and paddled the same as a 3’. sure.
Oho!! I was gonna ask what the process was until I saw the molds down on the lower right there. So, he’s vaccum bagging sections; hull, inside nose, deck n’ rails, then laminating 'em together. Is there foam inside those rail sponsons? I’ve been playing around with the idea, though a friend turned me onto a slightly less ‘fixed’ arrangement of molded hull, foam rails ( bandsaw the hull to your preferred outline shape ) shaped and placed, the vaccum bag on a top lamination ( dunno if I’d call it a ‘deck lamination’ per se ) , set your fins and voila. This allows ( with a pretty big mold) quite a lot of variations - especially if the 'template as French curve ’ idea- using different parts of the mold for the hull as necessary - is followed. I was planning on glassing ( one side ) otherwise pretty useless blank I have kicking around the shop as a male mold for the hull. If I didn’t constrain myself to epoxy systems ( though that kinda cuts down my choices of foams for sponsons/rails ) then it’s a helluva sight cheaper with plain glass cloth and polyester resins. The drawback to a male mold system rather than the female mold system used above is, of course, that you’d have to polish the finished product rather than having a polished mold and that in turn results in a very nice surface right out of the mold. As you’d be doing quite a lot of lamination by the rails, it’s kind of reasonable to go with the male mold system. Okay, that’s my thinking, but I’d be very interested in more details of how this critter was built… doc…
Cool board.Is that guy sportin’ a grape smuggler though?
WOW! Too bad those are kneeboards.The surf media and surf pedestrian majority would never open their perception to something brilliant like those spoon fishes.The fish and the flex are not new ideas though a couple of f#@king kneeboarders rode similar craft what?? 30 yrs ago? My tennis racket has been carbon fiber for what?15 yrs?The surfing population is in reality a very closed minded culture as a whole.Anyway beautiful boards and how would someone purchase one?
I met Troy on Oahu at the 1978 Expression Session Pipeline Contest. He snatched it away in 10foot Pipe. He’s been making them since before that. He is a regular sojourner to Puerto Escondido, and member of the disentegrating Wedge Crew.
I questioned him abit about his design once, in anticipation of making one. I dont remember too much. I would assume there is ‘some’ foam in there, but not much as in Greenoughs use of foam. But he uses fishing rod along the rails from about half way down. The fishing rod is wrapped up in the layers of course. Strengthens the board and keeps it from breaking. He was a professional fiberglass mold maker at one time.
ok, that’d make sense - if you wanted a stiffener why go to the trouble of making mandrels, laminating, etc when you can get off-the-shelf fishing rod blanks in just about any combo of stiffness and strength you wanted. So often we try to re-invent the wheel when there’s something cheap and easy to use. Of course, when you hear about that there is this instanr ‘moment of duuh’ when you see such a nice, simple solution to the problem. Former pro mold maker…doesn’t surprise me in the least. Nice work. Now it’s got me thinking about how to make a mold that’d be a little bendable/adaptable, though a simple female mold of lauan and such would be a good first step before going a bit crazy with it all… Thanks, info much appreciated. doc…
your welcome Doc Beeline.