John M posted about Stretch . . . but I looked on his (Stretch) site and found he puts channels in his decks.
Searched but nothing came up
I saw in surfermag shapers would put a 1-2in piece of foam on the deck to make it flat or concave . . .
Is stretch doing the same thing? Making the deck flat or concave, and the channels are there to start the point where the crowning of the rails starts?
Or is it for strength or flexibility?
Thanks ahead of time
we do that on some of our longboards and a few shortboard.
the reason is for strength and a bit of a pain for the glasser/sander…
they break less, the weave make a parabolic stringer and that totally increase the strength but there is a compromise to it…less flex.
we have a sweet little tool to make them fast, its kinda of a U shaped sand block, it follow the rail as it cut to the channel. works good and its fast.
to me, flex is better than strength and that why i dont ride surftech…
cheers
another thought of mine would be since his boards go airborn quite a bit it sould create a bit of a hand grip for the rider.
Louis,
A Stiff board will be less strong as it doesn’t have the ability to flex under load, which increases it’s strength. A material that is too stiff is not stronger, thats why alot of those Surftech’s snap. I was under the impression that those channels were shallow and then filled with resin, but it doesn’t seem to be that way. Doing it like that would create a sort of resin perimeter stringer. I could see a benefit with that, but not if the channels aren’t filled. I know there others on here who have done rail channels, hopefully they will chime in.
this has all been discussed before: HERE
yeah true, sorry my english isnt all that good,
i wanted to say stiff, not strenght in a strong way but in a stiff way.
thanks for making it clear…
i know what you mean about memory. flex absorbs lots of shocks.
the channel on the deck really increase the stifness if they are filled but they dont need to be deep to feel a difference in the feel.
cheers
I asked a friend of mine, Jeremy Sherwin about those when he borrowed one from Strech, and Jeremy said Strech told him that they were for stiffness and he also said something along the lines “they just feel so good when you hold them”
-chris
I’m not sure what they do for the board, but the only one I’ve seen up close was on an old Greg Loehr shortboard…first board I learned to ride on, and as a kid I thought that they were just for grip for duckdiving. Amazing how very little a 12-year old can know about surfboard design… 
Cole posted up on surfer mag a while back saying that he and flecher found that those channels stiffen the rail. I wish i could find the post but i con’t so i’m gonna have to paraphrase cole…sorry.
Just for reference guys, the quads have a whole lot of single concave, almost 1/4 inch.
sweet . . . thanks for posting the rail channel thread . . . It’s funny I would’ve never thought to use rail channels, mainly
because I’m thinking of the ones that Rich Harbour to help with noseriding . . .
sways is dope (as in good). . . thousand years worth of shaping knowledge (if you add up all the years and exp of posters) . . .
Well, when it comes to rail channels, I always thought along the lines of corrugated fiberglass panels: http://www.ridoutplastics.com/fiberglass-corrugated-panel.html …Why do you think they add the corrugations? It’s funny that they are making a comeback- I remember trying to fix a brand new, snapped in half board in the early 90’s- it had rail channels too. -Carl
Hopefully Greg chimes in. Pretty sure him and Sammy started doing it at the RR shop years ago. Spoken with Sam about it many times. I personally feel it adds strength. How much it messes with the flex characteristics…not sure. You got me. No they are not filled in with resin though. Might have an extra little pool of resin from the glasser not applying as much pressure or letting it pool slightly. Also depends if they fold the bottom lap into it or stop the lap line under it. I have made em for kids who love em because like someone said…they feel like they are grips. Duckdives, airs… I thought it was funny that some of the better surfers suprisingly enjoyed them. I look at as more structual and less hand grips.
I think Cruzmaster stated the intended purpose. Stiffening the rail to try and counter act the natural tendency of the board to twist when flexed.
christian
so if i were to get say a plank
and route channels down the side
it would stiffen the plank?
in which case it could be used in building and such.
or does it only apply to a sandwhich panel?
Louis,
I wonder if you might have a picture of the U shaped sand block that you referenced for cutting in the deck channels? I have always drawn in a line with a marking tool and then cut the channel in with a dowel covered with sandpaper. It sounds like your tool may yield faster and more reliable results.
Thanks in advance…
John
Here’s a beauty (Noel’s 10_02) by Steve Forstall… I love that shape and stringer configuration!
That is a fine looking surfboard…
Any idea on the dimensions? Also, still looking for a photo of the u-shaped tool to cut the deck channels that was referenced in an earlier post on this thread.
Thanks!
John
so if i were to get say a plank
and route channels down the side
it would stiffen the plank?
in which case it could be used in building and such.
or does it only apply to a sandwhich panel?
No it would not stiffen the plank, it would make it more flexible, the channel is corrugating the thin outside layer, which is a different story.
so what your saying roy
is that it stiffens the skin,
but makes the blank more flexible.
hmm
so has anyone done any tests?
it might help a pupe keeps its lively feeling for longer than a week
The “channels” routed into the plank would be parallel, no?
That would be a BIG difference compared to creating two curved channels that follow the outline of the board.
I always find it useful to picture myself as the material and try to deduce how movements and forces would alter my form and create areas of tension/compression.
