Strengthening a Surfboard

[Mug]

Has anybody tried to strenthen a common Clark board (i think polyester with E-glass) with Carbon Fiber. I was thinking of vacuum bagging 1 or 2 layers to make it kiteworthy.

[nab1000]

Bump (i have same qeustion)

[Kevin Salter]

For a used surfboard I glass an extra layer of 6oz top and bottom to cover the standing area.
You will probably have to hand sand due to dents etc to give you a good key for the extra glass.
I lap the extra layers round the rails for strength and put in footstrap plugs as well.

You can use epoxy or polyester resin over existing polyester, and finish by sanding to fair in edges ,wet and dry 80gt by hand works well, then finish with 600gt.

By glassing just the middle of the board it doesnt add to much extra weight and puts the strength where you need it.
I ride strapped in waves, and jump on a 5ft 6" board that I did the above to and It has held up really well.

[Mug]

That sounds pretty good, i presume that you meant s-2 fiberglass, that seems pretty strong. Maybe for my next board that I'll build, i'll look into carbon fiber composite construction. Also I was wondering i anyone had experience with Kevlar surfboards and what their opinion is on Kevlar over Carbon Fiber (price mainly seems the main consideration for me).

[scklandl]

dont use carbon, its very expensive, hard to source, and completely unessecary. it also degrades very quickly in the sun and is very suseptable to poor handlin ie greasy fingers.

s-2 is pretty much useless too, it adds 20% strength gains and costs twice as much,

you can acjieve that same 20% strength with a harness weave e glass, and have a significant reduction in resin weight due to its high fiber to resin ratio.

use polyester resin unless you know its an epoxy board, and I suggest two layers of 6 oz of regular weave or at least one of 10oz harness weave. 6 oz wont cut it.

as far as kevlar or carbon for your future board, a full carbon surboard would cost a fortune, kevlars not much stronger than s glass, just more abrasion resistant. and the only thing youll gain with either is weight reduction, which on a kitesurfboard is so not necessary, weight is actually a good thing (look at towboards) because the board wont bounce as much in the chop

[Trant]

My ex-housemate had a surf board made with a kevlar deck to resist the inevitable deck damage most boards get when you use them for kitesurfing.
(caused by pressure from your heels etc.)

It worked really well, there was minimal damage after 6 months.

[scklandl]

sorry trant, but the only thing that a kevlar deck would do is prevent surface scratching, since its covered in wax, whatever.

kevlar is not extraordinarily stiff, for that matter neither is carbon (its carbons ability to quickly and fully return to its cured position that gives it a "stiff like" quality.

a full kevlar would prevent the board from scratching through the fibers if the board got away from you and tossed against the beach a few. Kevlars selling quality is abrasion resistance, and since most boards have a hot coat theres little chance of ever needed that quality.

your roommates board was in good shape cuz he takes care of his gear, not because its kevlar

[Trant]

Well I don't pretend to be an expert. All I know is that his previous boards always looked pretty beaten up after 3 months. Then this one lasted the course.

Maybe it was a placebo effect; i.e he paid the extra money so he took better care of his gear!

[Nico]

My experience:
Got this brand new polyester fish 6'4" from prolimit.
Routed out 6mm the standing zone of the board (this hurts on a new board). Put in 5mm pvc sandwich foam (light brown colour) in the routed out area and covered it up with a sheet of aramid/carbon mix, which i then covered up with two very thin layers of glass. The lot was soaked in epoxy, and bobs your uncle. Had about 15 sessions with this board without a hint of indentation.(strapless wave kiting)
Nico

[Kevin Salter]

For a new board get the lay up two layers 6oz top and bottom in e glass with a double concave deck in the standing areas, this means you can glue extra deck pads into the concaves then put a deck pad over the top. this is the strongest lightest way without getting into carbon etc.

If you use carbon under the heel area cover it with pads to protect from UV. If you go this way a new surfboard wont cost much more than a standard one. Avoid FCS fins if possible, they break off easily. Futures boxs or well glassed on fins are much stonger and they only need to be toed in to 2" off the nose for kiting.