L'autre jour j'hésitais à me prendre une tabou 3s 2015 limited, en freeride medium+ baston pour les rares jours où ça souffle.
Depuis "toujours" on voit bien la couche carbone kevlar sous une fine strat verre sur les 3S ltd.
J'avais une bonne option en germanie, dans les 1150 euros neuve à Noël. J'ai fait ma pince en attendant d'être rentré à la frontière pour économiser 50 euros de livraison...
Planche vendue.
Pas grave, ils ont les 2016 à peine plus cher. La 2016, elle a une maladie : elle est blanche et noire. Vérification avant de commander : c'est plus du carbone kevlar, c'est du "carbon innegra sandwich".
C'est quoi ce truc, connais pas, commande pas
Après quelques lectures c'est le tissus à la mode dans les brochures commerciales et... chez Cobra.
Un peu de publi reportage sur le site fanatic :
http://www.fanatic.com/fr/windsurfing/technology/Chez SB :
http://www.star-board-windsurfing.com/2 ... echnology/et partout ailleurs ou presque.
Je vous laisse vous faire une idée avant d'aller plus loin, notez que l'on compare du 4 couches et du 2 couches au passage :
https://www.youtube.com/watch?v=0N-LiWRA7RQhttps://www.youtube.com/watch?time_cont ... cwgvHblTlkUn pdf de la marque :
http://www.noahsmarine.com/mmNM/Images/ ... tation.pdfhttp://www.innegratech.com/Une page instructive en français :
http://guidedupetitshapeur.creerforumsg ... c-est-quoiGlobalement, à mon avis de non spécialiste :
L'Innegra c'est super pour un fabriquant de kayak ou garder le bateau entier en raid est important. Tu mets du scotch sur la ligne de rupture pour étanchéifier, et tu rentres. Idem pour limiter les débris en F1. tu gardes les morceaux attachés. Pour la planche... je dubite encore.
La fibre ne pompe ni flotte ni résine donc faut "l'englober" de résine. Ça reste pénible à mettre en œuvre, surtout à bien mettre en œuvre.
C'est costaud, mais ça s'allonge fort avant rupture donc la résine craque avant la fibre. Les morceaux restent ensemble... mais c'est cassé quand même dans le cas d'une planche.
C'est moins rigide que le reste. Comme c'est pas trop dense on peut en mettre plus.
Si impact tu craques pas la peau mais tu risques de délaminer. Chiant à poncer, chiant à réparer (kevlar idem).
On va nous expliquer que le touché de plan d'eau est plus naturel, façon élégante de dire que c'est plutôt doux. Ça permet peut être à cobra de limiter les planches cassées en deux, à la rigueur...
Bilan pas de 3s ltd, je boude.
Pour les tissus :
Partial Data is always a problem, particularly when leavened with personal bias. Here's my incomplete take on Kevlar, Innegra, Glass, including Basalt, and Carbon, also with incomplete data
E glass, Basalt and S glass are silica variants, 2.5 times as heavy as water, with tensile strengths, ie breaking in tension, of 500ksi for E, 600 for Basalt and 650 for S. Modulus of stiffness is, 10msi, 11, 12 respectively, again about a 10% difference. Costs vary, E is $6/lb, Basalt and S ~ $20/lb. Basalt has an attractive brownish color.
Tuff Weave is polyester/Diolon with a specific gravity of 1.4 that of water. Elongation to break is 14 %, about three times glasses ~5% with a tensile strength 180 ksi, about a third of the glasses, but it's modulus is 11 msi, same as basalts. So it flexes quite easily but will take more impact than glass and costs about $10/lb, a little more than E glass.
Seems like it'd best be used inside hulls, but the elongation is past what our resins can match; it's a less expensive substitute for Kevlar. It's weight, about half glass's yields a 25% savings in similar panel thickness, as resin weighs the same for everything.
Kevlar [49] is also about 1.4 times the weight of water but has tensile strength of 580 ksi, elongation to break of 2.8%, ~ half glass' and stiffness of 19 msi, twice that of glass and Poly. So it's stronger in tension and stiffness at about half the weight of glass. With resin added, that leaves panel weight of ~ 75% of similar volume glass panels and about the same as Poly except it's much stronger, but there are problems. Kevlar costs ~ $25/ lbs, it doesn't bond with resin, it's captured in it, and it's hydrophyllic, absorbing 7% of it's weigh in water where freezing/thawing, etc. etc. Silica and Poly absorb less than 1% water by weight.
Enter Innegra, a High Density PolyPropolene/polyolefin with Sp Gr. of .84, significantly lighter than water. It has physicals below glass or poly with those numbers improving because it is so light we can use more of it. It's elongation to break is 10%, a problem with resin physical characteristic, and while it absorbs no water, 0.0%, it does not bond with resin any better than Kevlar. 100% Innegra Layers need a veil mat to improve adhesion and Innegra floats on resin so must be vacuum bagged, preferably dry bagged for debulking. Innegra costs about $20/lb and needs to be mixed with other fibers. Glass, Basalt and Carbon are the available choices.
Carbon has a Sp G of 1.8, tensile strength of ~600 to 800 kst, modulus of 33-40 msi, elongation to break of 1.5-1.8%, zero water absorption and cost $50/lb or more. It is the good stuff!It can be blended or co-mingled in individual threads in roughly a 50/50 mixture. or co woven, with Innegra in one axis, Basalt or Carbon in the other. Quad weave, Innegra and in every other thread in both directions is the most complex offering. The blending solves bonding issues, and the Innegra "fail safes" it's fabric mate. All the mingling and multiple weaves cost more money than straight Innegra.
And that's where my data runs out. Early testing suggested co-mingled thread was higher in impact resistance but recent anecdotal information prefers the more expensive quad weave product. We can suspect bi weaves fail as Kev/Carbon bi-weaves do, zippering in one direction. Innegra/Carbon blends are lighter and stronger than Basalt/Innegra but they cost significantly more. As the research studies haven't arrived yet, I'm guessing too.
So it remains to be seen if Innegra will replace or compete with Kevlar as the intermediate priced laminate. Kev has had a good long run and M-5 is coming, in the words of Ian Tyson, "Someday Soon". We'll see about that too.
Connexion
M’enregistrer
FAQ
Rechercher
