Ola H. wrote: ↑
Fri Jul 26, 2019 9:13 am
I never made boards with channels, though I have been tempted at times. But I don't really think the marketing blurp is correct here. Adding rocker just in the center of the tail (rather than at the rails) will not make the board a whole lot easier to turn. The channels will rather create traction in a short turn, ie grip.
In the 90´s I made a board with channels on a twinser to improve the grip. I could not really tell the difference. As a twinser it was skipping out in the bottom turn at times, even in some glassy conditions and it kept on doing that. Adding a smaller centre fin again was much better. So since then I am using trifins.
As the whole tail will pretty much always in the water, it does not really matter if the tailkick is in the middle or on the rails. You get some shapers saying it has rocker in the rails to turn on and a flatter centre to plane on but it´s the same as before, as the whole tail is in the water, the negative effects remain.
With my Wave shapes (V3, V4 and V5) I give extra rocker to the front rails, in the shoulder and leave the centre area rocker flat. The whole area is in the water when getting planing but the centre lifts out of the water when you put the board on the rail. The difference in rocker is some 16mm, which is a lot.