In a typical Sways way, Id like to ask what people know about a very well known but largely unknown component of surfcraft.
Channels.
Ive seen rounded ones on Greg Noll "Da Cat" boards from the 60's, 4 and six channel versions in the 80's, from razor sharp to sublte 'Fluid Foils' ripples. They were all the go for Pipe, Mundaka and the like and were on lots of boards even in the 6 foot range, but are strangley absent from an industry thats hooked on 'reinvention of ideas past'.
Maybe its because machines cant shape channels.
Channels are a concentrated version of the concave bottom contour thats highly popular nowadays, and the dominance of concaves would suggest it will only be a matter of time before the distillation of concave theory results in the return of channels.
BUT when I ask, "what do they do" and more importantly, "HOW do they work", the best answer Ive heard is,
well, yeah, they ahh, focus and concentrate the energy ....... (awkward silence)
Can anyone share their knowledge of How channels work ?
And How does the shape of the channel alter the performance ?
Channels , I guess, are only effective on steeper faces but how much water goes across the board or up the face ? What is the direction of the flow, taking into account the speed of the craft ?
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/channelwaterflow.jpg[/IMG]
And so which shape of channel would be the most effective ?
Heres a few different cross-sections...
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/channelvariations.jpg[/IMG]
Most channels have been of the rounded or angular types but what would the result be for the other shapes?
I have been shaping different shaped channels into maching shaped blanks with identical thickness, planshape etc,... and starting with an original board (the "CONTROL" board ) with a flat bottom.
Ive found that the moment you start adding contours/channels, you are taking away from an uninterupted planing area and the board loses planing efficiency.
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/06mar10001a.jpg[/IMG]
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/06mar10004a.jpg[/IMG]
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/Nokiapics015a.jpg[/IMG]
Nose entry.
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/Contours1March2010082.jpg[/IMG]
Tail exit.
[IMG]http://i153.photobucket.com/albums/s225/SURFFOILS/Contours4March2010088.jpg[/IMG]
That sounds pretty logical but you'd think that if you install a 'slot' or 'block' channel it wouldnt make much of a diff, but it does. Maybe its because the planing surfaces arent on the same plane (or synch) or because of the small loss of foam and resultant bouyancy, but the change is quite obvious.
And because its obvious, the need to find the most efficient shape is interesting... How many people have tried other shapes ?
In the variations Ive tried the position of the channels do provide lateral grip on steep waves that is in line with their location on the board. Forward channels require the rider to move forward to balance the lateral grip.
And Ive been doing some channels as Continuous Depth Channels so theres no alteration of rocker curve, the channels depth is the same for its complete length.
Anyway thats what Ive been testing, can anyone suggest their own theories, tests and results or speculation.
Thanks.
A simple 'fuck off' will suffice.