I have been building a lot of boards with a 3/8" (9mm) thick wood
core and glass skin. Except for the weight, I really like the way
they ride and I think the flex and lack of volume really play a big
role in the performance.
I want to make an identical shape in corecell to try to get the
weight down. If I use 9mm corecell and a heavier laminate will it
work or is the board destined for failure if I go this thin?
Anyone have any ideas on how heavy I would have to make the glass
skin?
the historically safe recipe has been 18 oz glass top and bottom on a
3/4 in core.
if you cut the core thickness in half (3/8 in), you'll need to use 4
times as much glass (72 oz) to keep the stress comparable.
-that might be as heavy as the plywood...
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I weigh 185 pounds, what is that about 85kg?
If I use 4 times the glass I should end up with a board that has
about the same stifness, right?
I want the board to be flexible, I just don't want it to snap in
half. How much glass do they use on snowboards? They are thin and
seem to be able to bend quite a bit without snapping.
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if we stick with the same example;
the core thickness is cut in half to .375",
but the skin is increased 4x (approx .1")
the board stiffness will be about the same.
possibly a little stiffer due to the high skin thickness.
I'm just guessing, but i doubt 72oz top and bottom is required.
I would consider alot less (30 oz) on the bottom and see how you like
the flex.
assuming the board is around 140cm, the stresses shouldn't be that
high.
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The board I want to duplicate with the foam core is 120x39
I am thinking I will use a triaxial fabric like I have heard is used
with snowboards. My understanding is that the non-woven fibers
require a lot less resin so that should help keep the weight down.
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That sounds pretty good.
I figure with most layups: 50% is resin and only half of the glass is
aligned for bending stress'.
The triax will be a big improvement.
If the weights are acceptable for you. I would guess that 30-35 oz.
top and bottom, with a little extra under your feet (just for luck)
would work just fine.