What are peoples thoughts on a double concave bottom in the tail for a surf SUP? or is it possible to go from a double concave to a v? What benefits and disadvantages would come from this? Just doing an assignment for uni and would like some thoughts.....
I'm no expert but my thoughts on concaves are that they increase speed by trapping air and getting it to flow between the board and the water unsticking the board from the water.. The norm seems to be a single concave in the nose area feeding into a double concave in the middle of the board then fading to a normal v in the tail area.. These concaves are often so slight that you need a flat edge to see them and some are only a millimeter or two deep.. When you get a double concaves fading out through the tail it's sometimes called a spiral v as the v increases and also sometimes the concaves don't go all the way to the rail to prevent an edge that can be a bit catchy.. I'm not sure if that helps any? (with your question)
DJ
D J sounds like he knows what hes on about both my Dc8.8 and 8 .10 have the concaves and they rip
I would give Dale a call on the benfits
or if your down this way have a surf on one my Dcs the surf report for scotts head onlly 2ft clean waves just got back water temp 24%
there has been a sup explosion at scotts counted 6 today
Phill / Downwinder,
I was a massive fan of singles a while back... They go unreal. But now I'm focusing on quads, and I love them. You can drive them harder. But search out a few True Ames single fins, and try a few different fins in the board. But of course, the fin that MR supplies will also be a great one. Nothing lost in trying a few out though...
Simon
Oh yeah... concaves... yes, big fan of Single to Double to Vee, on most craft....
so can anyone tell me where the doubles start and finish before turning into the v? as i mentioned earlier this is for an assignment and potential a board to be built one day.
I think the question was what are the benifits of concave/vee throughout the hull of a surfcraft.Basically concave gives lift which creates speed and vee sucks to the face and gives the craft extra rail to rail manouverability.To test this get a table spoon and put it under a running tap you will notice that the concave side skipps out of the water where as the convex (vee) side sucks right into the running water.So whare to put what?Concave under the rider for paddle speed and down the line wave speed.Vee under the riders back foot so the craft wants to stay stuck to the wave when turning and for rail to rail manouvering.Another thought especially concerning SUP,concave gets a craft floating on the rails which is quite stable where as vee will make a craft rock from the centre which is rather unstable.
Hope this helps.
I left out doubble concaves.there are several types of doubble concave.Flat doubbles are just matching concaves on each side of the stringer.Reverse doubbles are concaves shaped into a vee bottom so if you were to put a straight edge on it you would first see a vee from the stringer out to both rails and then you would notice a concave shaped into each side.As you can see there are so many variables its hard to put a finger on what works best,remember the running water test and try to use your vee's and concaves to your advantage in the surf.
Thanks gumballs that helps out a bucket load! now just the decision making process of what I would like the SUP design to be so I can present it to the lecturer with appropriate resource and justification
well find a man if you are that way inclined or if you have some coin buy some toys, doesnt it hurt though?