Can the crowd explain to me the theory of bump wings? Are they thought to provide a pivot point for turns? In particular I wonder why they are so often implemented on fish templates, as most people (myself included) like to swoop and carve on a fish… I have zero experience riding boards with bump wings, so be gentle…
You can do the same thing with rail curve and many shapers do. Bumps don’t create nearly as radical changes in water flow as do hard wings. More subtle. I love double flyers…but I also like the same type of rail curve. Little difference in ride really. Hard wings…all over the place.
The simplest theory may be the simplest answer. The break at the bump allows for a narrower tail, thus more hold in turns with a fuller outline in front of the bump.
Ok, so how does a HARD wing affect takeoff and down-the-line speed?
I would assume that it would allow water to release off the same hard edge, with the same forward/midpoint width, as if the width had been carried full aft (like, say, on a lis-style fish), and thus would allow you to keep the squirty speed of a very wide-tailed board, but with the last 10-12" of tail pulled in for tighter turning and better holding.
Do I assume correctly, or make an ass out of u and me?
I like wings. They look cool. They make my board feel fast. Does that make me a kook?
Here is my version of this type of board which is a lot more extreme, I call it the “Cuttlefish” because it looks a lot like one.
Basically, I draw out a rounded pin tail out line first, then I add the wing about 16" up from the tail and 3/4" out from the existing outline. I then flow in a curve from the wide point to the apex of this wing.
The next step is to take the same template and use the rounded pintail to draw a much more pulled tail so that I end up with as little tail as possible behind the wing.
I position the leading edge of the fin so that it is lined up with the wing. The bottom is shaped with a radical double barrel concave where the deepest portion of the concave is close to the rail and apexed at the tip of the wing.
The rails behind the wing are left totally vertical and square for maximum release. Also the last 7" of the tail is very heavily rockered!
As you can see in the attached photo this one is setup as a quad. But I first started making these in 1970 as single fins.
All I can say about them is that they are the most amazing boards to ride, unbelievably fast and yet very loose with a lot of control. Because of the position of the wing, concave, and fins to where the back foot goes they have incredible control with just slight weight shifts.
I even have a 9’ 1" longboard this shape with a concave deck that is pure liquid to ride, although that one is setup as a 2+1.
They look a lot like bump outline boards except for the tail design.
Fun, fun!
-Robin
PS: Hope the picture comes through as this is my first attempt at an inline picture!
The quad setup really seems to make a big difference on this board. They still worked very well as a thruster, but the quad just makes them even more maneuverable and faster, plus there are more options as a quad because you can switch the fins around to radically change the characteristics of the board. Here is a photo of the fin setup, you can also see the tail rocker very clearly in this photo.
It still worked really well as a 2+1 on the longboard I have so the shape is definitely a strong contributor to the overall performance. That said if I was to do the longboard version again I would do it as a quad.
Unfortunately, it is not able to levitate on it’s own, hence the arm in the photo!