I am putting together a quasi fish 121914.25. So far so good. Only problem is I don’t want to profile the board until I am sure of the amount of foam that I need to leave in the tail so that I can put channels on it. The channels I want to put in are the ones that fade in from a little over a foot in front of the side fins (it’s a thruster) become gradually deeper and then fade out again through the tail section. In all there should be four steps. ie; a large shaped one in the centre fading out just in front of the back fin and two side ones fading out in front of the side fins…if you get what I mean…I hope! I am using an Hitachi planer and have done quite a few boards (50 odd) but never tried the channel thing so any advice on placement, technique, depth etc would be much appreciated. keep the vibe cheers
Put four channels. The outside channels should run along the edge of your outter fin. The inside channels should be evenly distributed from the outters, but prefereably a wider distance between the inner two. The depth at the deepest point should be no more that 1/2 inch in order to fade out nicely. Here is a way to do it. It may sound kinda strange but if you don’t have a plan this is the way to do it(kiinda like making a template for the first time. Draw your outside liine as I said along a line that follows the outter fin or you can angle it ever further out from the nose(like when setting fins). Take your dowel and shape in the first outside channel. Once perfect ,then duplicate it on the other side. Now, draw in one of the inner channels. Start digging it out with a dowel or round sureform, duplicate on other side. Your first ones will be look and feel type of thing. By the way, the channels you are talking about are called “belly channels”. Good luck.
Forgotm to tell you the rest. Sorry. Now that you have the grooves in place, remove the foam in between the grooves. A sanding block with forty grit works good, then work up to the fine screen and then fine sand paper. Luck
I’ve never tried (riding or shaping) channels, divits, or any other bottom modification (besides concave). Someone please explain to me the proven advantages of incorporating channels/etc. into a (shortboard) design, as opposed to a flat bottom. Since water moves fastest over a flat surface, are channels mainly meant for lateral stabilization, drive, or what? I should probably ride a channelled board in the same session with a regular board, so I can feel the difference for myself. Until then, any advice will do.
I believe that channels allow water to flow through the boards rocker, therefore you can have more rocker with the speed of a flatter board. SteveA.
I believe that channels allow water to flow through the boards rocker, > therefore you can have more rocker with the speed of a flatter board. > SteveA. from what i understand, channels offer more holding power on steep clean waves, allowing the surfer to push harder thru turns, maintain the critical high line, and avoid the slippery feel flat bottoms sometimes have. personally i like double concaves in the back, but either way, on shortboards i feel channelled or concaved bottoms are faster than totally flat bottoms, since speed is coming primarily from the rider, pumping/turning the board. channels/concaves also draw on the Venturi effect(water speed increases when passing from a larger area thru a smaller one, increasing pressure etc.) helping increase speed.
Forgotm to tell you the rest. Sorry. Now that you have the grooves in > place, remove the foam in between the grooves. A sanding block with forty > grit works good, then work up to the fine screen and then fine sand paper.>>> Luck Thanks a lot Steve, makes sense, I’ll givi it a try and hopefully I can offer some helpful advice too in the future. Oh, and thanks to you too Mike and any of the other types at Swaylocks
A directional/channeled bottom design can allow a narrower template because of compensation for the gain in dynamic lift and also affords the shaper an opportunity to incorporate dual rocker profiles: one (usually flatter) that runs down the board through the concaves and the other (usually with more curve)which follows the edges of the template. Generally speaking, it is important to balance the pronounced effects of concaves/channels that are placed in the bottom surface with some form of displacement, i.e. chines, lifted and rolled edges, etc. Also, while this type of design normally offers greatly improved low-end speed, it will likely be more sensitive to uneven surface conditions because of its high velocity potential. When one considers creating surfcraft that may end up wanting to fly, rather than surf, the shaper`s potent alchemy of blending and balancing opposing (low and high pressure) forces becomes even more critical to successful design.