I’m seeing an increase in boards with carbon fiber rails. Here is a video demonstrating why CF and regular fiberglass don’t mix well in the same structure.
Would someone please do the proper imbed of the video since I am clueless. Thx
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I’m seeing an increase in boards with carbon fiber rails. Here is a video demonstrating why CF and regular fiberglass don’t mix well in the same structure.
Would someone please do the proper imbed of the video since I am clueless. Thx
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good video
“keep all your composites, homogenous”
sounds like an oxymoron
its ll looks I guess
Are his eyes any indication of what might happen if you mix CF and FG together?
Hilarious. I had not noticed. Maybe he has been up a while.
While I agree with his analysis of tensile strength in his material properties explanation, I have a feeling he might be missing the protection against punctures (dings) that the glass layers provide… an important part of the surfboard construction equation in my opinion. Snapped boards do happen but it seems like the little punctures are what add up as far as general wear and tear. I like his comparisons between ‘S’ Cloth and carbon in another video.
Not sure that this explanation is at all relevant to surfboards where force limits are generally much lower than, say, a high end carbon fibre bicycle frame, most of which are laid up with several layers of carbon fibre sheets with different orientations and tensile strengths. Why? In order to tune the composite structure for the load and desired flex/stifness characteristics. Moreover, it is now increasingly common to see the final outer layer of said frames to consist of the high modulus sheet to improve impact reistance, and thus total failure of the structure beneath.
Probably not a great idea for boat masts or airplane wings, though. Or anything high aspect where movement along the long axis is expected or desirable.
On the other hand, working with carbon is hazardous in a way quite unlike fibreglass, and more like asbestos. Begs the question–what use is CF in surfboards any way?
Are you saying that CF (polymer) is more fibril (nasty long aspect lung-plugging fiber) like asbestos than fiberglass, which already shares its chemical makeup (silicate) with asbestos?
The way I see it, any surfboard material (wood, glass, resin, CF, foam, paint, glue, solvents, etc.) being handled is an inhalation hazard without proper mask and ventilation.
Funny—- It’s a common practice to overlay four ounce E over Carbon and I have done this many times without a hitch.
John, some skateboard deck builders who like to use CF use a layer of FG over (outside) to protect the underlying layer of carbon from abrasion.
The outer skin would stretch more than the inner skin during (outward) flex. So if CF provides some desired advantage, an inner layer of CF with an outer skin of FG coud be beneficial.
That next video about CF, FG and Kevlar is the one you sent me the link to a while back. That video gives and excellent summary/comparison of the 3 composites. The take home for me was that for most composite applications, FG was the better all-purpose material.
Thanks stoneburner - I think that it (carbon) has just sort of become a ‘sexy’ marketing material. It is often referred to as being so light and strong but in the real world of surfboards, it doesn’t provide much more than eye candy. And I’m not knocking eye candy. As far as being ding resistant? Not so much. Stiffening a stringerless board? Yes, but ‘S’ cloth, pound for pound has approximately the same tensile qualities and is cheaper. It just doesn’t look as cool.
Carbon fiber cloth only achieves its full potential when vacuum bagged. Mold forms, bathtubs, surfboards, space shuttle parts. Hand laid CF looks cool but it becomes an expensive and inferior product compared to vacuum bagged or vaccumed autoclaved/molded CF stuff.
Mixing CF with other composites: Like most techy things in the surfboard industry it has been ripped off from windsurfing or directly intorduced initially by Randy French back in the day. Though much of what you see that is obvious with CF on surfboards it is probably less functional than the incresed price of the board suggests. Windsufing on the other hand and the introduction of surftechs has all the tech performance buried under the paintjob or wood composite top. CF has proven its effectiveness mixing composites with low weigth, high strength and increased performance in many sport, automotive, space/airline and alternative energy industries. Corecork is another complimentary composite material especially designed to use with CF. acting as a filler cutting down expensive, keeping it strong. All our wind turbine blades on oahu, where the tips are going about 200mph, are CF composites.
A vacuum bagged exposed CF surfboard is way safer in regards to hazardous environmental exposure than an E glass hand laid board. By vacuum bagging you eliminate the need for a filler coat because it is done with the initial pull or infusion. Careful consideration of your laps when vac bagging CF cuts sanding time way down possibly eliminating the need to even touch them with the bottom lamination.
If we’re talking EPS surfboards I think the video cements the need for flexible materials to be mixed with eglass so that the eglass can stretch further without breaking??
Carbon fiber is super stiff and in short HP surfboards increases the resonance/vibration of the plastic EPS foam. Thats bad.
Carbon/eps boards fly down the line feeling awesome but have strange wobbles when hitting chop, driving off a hard bottom turn or at the end of cut backs there is no give or flex in the tail and the board can skip accross the face resulting in a tail slide.
I’ve been vac bagging innegra and eglass in stringerless EPS with better surfing results but the dificulties in laminating is doing my head in.
Proper flex and durability, I’m reallying thinking that Bert Burger and Josh Dowling figured EPS out long ago with their posted methods…
Yes they did. And Mr Loehr helped as well.
one of Bert’s first post was a pseudo build of a surftech or a seatrend board developed in the 80’s.
not so simple with composits. the comparative way we use with isotrope homogenous material in mechanical designing is too far from reality with composits. So what this guy show is right with glass/carbon in axis in static tensil stress. Hazardous to extrapolate for flexural dynamic stress. So people can still try everything to fine the magic sauce and hope to find it. But is there à universal magic system ? mmmhhh! a religious asking… in général people can become agressive when they speak about god…
Basalt for Eps is a good alternative to Carbon, Natural flex, good impact strength and can look pretty sweet too.
Wow fantastic post. I’m a noob in making boards, and never thought about this before.
Agree. Good comment and advice. I still use it as a sacrificial layer when I do regular weave carbon boards.
All the best
Oh no!
Quick somebody tell these airplane, ski, snowboard and longboard manifactures that they need to stop doing this…
And why would you put it as a top layer? Its super sensitive and will break easily if hit onto something hard… You need to protect carbon fibers.
Picture Credits: Composite World and JSkis
As a sacrificial layer, most of it gets sanded off. Minimizes the need for a fill coat.