Hi everysurfer,
Cordura, even uncoated, isn’t make for composit build. Teflon treatement, that give the higher abrasion resistance to polyamide, unable resin bond.
Fibers for composits are “ensimé” (don’t know in english) to adhere with resin. Dilène/xynole, better vectran are HT polymere fiber compatible for use with composits.
Hi Lemat,
Uncoated Cordura has no treatment on it. No Teflon, no urethane, nothing. It is a tightly woven nylon 6,6 fabric. It bonds excellently with epoxy. I have made multiple test samples, as well as surfboards with it. There are no bonding issues.
It can be rurchased in a raw state, where it has not yet been heat treated, and the fibers are unbonded. It can be purchased “grey” which is after heat treatment, but nothing more. It can be purchased dyed, but untreated (which is what I use). Or it can be purchased treated, where it has been coated with waterproofing.
Treated Cordura is different. It has many treatment options. Urethane is the most common, but teflon is available as well. Urethane treatment will bond with epoxy, but does not drape, or saturate, so it is difficult to use.
With its tight weave, uncoated Cordura takes different techniques than fiberglass to wet out.
So my question is, do any pro builders object to me posting how to use it, and even more importaint, does anybody plan to try it, and want to know how to use it?
this new EPS I’m building blanks from is tightly fused stuff, nice quality real happy with it, but by the time I glass to spec with the intention of durabilty, it’s about the same weight as PU/poly schedule.
Made a clone of my favortie Cordell thruster, weight difference was nearly same in the end, more fabric, less foam. My board much whiter, new RR PH optical brightener.
Hi Vaeske,
Optical brightener gives a blue tint to make it appear white. Cerex N-Fusion titanium white has titaninium pigment added to it, so it isn’t a tint. but really is whiter
Thanks Mark, curious what the technique is on Cerex, never used it. Where you buy for the best price?
EDIT: I should probably read this entire thread. I’ll PM you if I have questions. thanks.
my nylon arrived yesterday. Despite some caution to bag it only, I went ahead and tried a hand layup. Turned out really nice. I noticed the stuff likes to ridge a bit on the foam as you drape & position the fabric, but a little care and technique, it lays down and wets out like every other cloth. It’s similar to this stuff I’ve been using from ACP (my brother built airfcraft wings for a few years, gave me a roll of veil material); that ACP roll is lighter weight non-woven brilliant white stuff, I’ve been doubling it up, and when I do that schedule, lamination requires extra care too.
Lam is pretty damn dry, nothing out of the ordinary. Went lighter on the deck with only a .7 nylon + 6oz warp + 4oz warp. Core is 1.5# See how this surfs, maybe a 2x4oz S-2 and a nylon ply over a 1.5 stringerless…
Wouldn’t mind trying Innegra, the stuff is made to work with EFS netting and some really light 2 oz glass, --this according to Surf DNA.
All of that, and now I’m ready to build some full wood boards.
Mark, curious about doubling down on .7 Cerex/Skinz and lightening glass sched even further. You tried it? Benefits? I wouldn’t be that brave hand lam in 2 layers of the stuff, but I don’t know; I’ve been able to really control my temps and squeegee techniques as of late. The resin is flowin’ these days…
EDIT: was thinking about the role of footballs patches for fin plugs when using Skinz or Cerex? Time wasted cutting glass or what?
I wouldn’t double layer the cerex against the foam. A single layer is fine. When placed against the foam, it helps prevent delamination, and seals the blank to reduce weight. Also makes the board whiter. Any thickness will do.
Cerex N-Fusion was made to be used as a surfacing veil. A second layer can be used on the surface to reinforce the hotcoat/ cover weave. But if you use it as a surface veil, you really need to bag it.
I’m pretty sure the Coil Kick surface is a textured surfacing veil that is covered with a spray coat, rather than a hot coat in their effort to reduce weight. If you are after that textured and ultra light weight skin, bag on some Cerex, and then spray with UPOL acrylic urethane.They still hotcoat the rails to smooth the laps, and help with water flow.
Using cerex as a replacement for fiberglass isn’t strong enough. If you want to replace the fiberglass, use Cordura. I posted a couple of sources a couple of pages back. After using Cordura, I don’t get why nobody started using it years ago. Different laminating method, but so much stronger than fiberglass.
As for the footballs, don’t use Cerex. Not strong enough for that kind of stress, and if you are using FCS Fusion, it doesn’t drape well enough.
I Use FCS Fusion, and what works really well is to laminate your Cerex layer on the bottom by itself. After it cures, route out for the plugs and set them. After the plugs are done, laminate as normal. Using a Sealer layer of Cerex against the blank really cuts down on the amount of epoxy that soaks into the foam.
But as I said before, if you are after the weight savings, you really need to use a wet out table and bag it.
I got 5 yds cordura on order, I take it this is also a bagged process 1x per side? little pricey at 160 D, but then again if it extends the life of the board…
Nice. That gave me an idea. Hank Johns swears that a good hand layup is toe to toe in terms of weight with the multi-stage bag process–faster, less overall resin used, less money to shoot a board…, splitting hairs, and if I end up bitching about an extra 10g of resin in a hand-laid board, that would give me insentive to lose some weight and start training…instead of bitching, which I happen to be good at lol … I don’t clock-in to glass boards, but I think I might build 2 identical wake surfers and test my mettle with this material via cab-o seal/micro coat w/the nylon.
I don’t think I’d use cab-o seal/micro as a top coat. Too weak and porous.
As for the weight savings, on a 6’-8" shortboard, you will save 50 to 75 grams of epoxy on every lamination. On your typical short board with one layer on bottom and two on the deck, 150 to 225 grams. So up to 1/2 a pound lighter. A full pound lighter than a typical polyester lay up.
Only downside is skill and time.
not as a top coat, as a seal coat imbedded w/the nylon as hand-layup pre-lam. slight amount of ballons and cab, not too much, just enough to bridge those voids in the blank while adhering the nylon down.
looking forward to bagging with your technique, that said, I’m gonna play the devil’s advocate for a second:
Saving weight via** straight epoxy + nylon** doesn’t make sense that it’s lighter in the end even if drawen tight with vacuum pressure. I don’t get the math behind that: straight resin fills in those voids + the weight of nylon in the blank whereas sealing with micros/cab-o is lighter, the resin stretches further over the blank. Why not just mirco seal, drape the nylon and screed it into the blank, scrape off excess, router fin plugs and glass? –This is what I want to try against the bag method.
The savings comes from how much wasted epoxy is in the blank and soaked in the nylon.
With my method, you aren’t filling the voids in the blank, but leaving them open. Epoxy with microbaloons is still heavier than air alone.
Also, nylon expands and swells as it soaks up the epoxy. The wet out table only lets the nylon veil take up what it can hold as it swells. When put on the blank, the pressure squeezes the nylon and hold it tight to the blank. Just enough epoxy is squeezed out onto the blank to hold it in place.
Wet out table, and no bag doesn’t apply enough epoxy onto the foam to get it to hold in place with a strong bond. The epoxy stays in the swolen nylon.
I understand. Thanks Mark…yeah, so then, suppose I wet out the nylon and drpe over the board…at that point might as well bag it…right
Magnets, it’s all done with magnets. Magnets are magic! =)
(Insane Clown Possie Referrence)
Latest'
Bottom us blanks red-1.2 oz N-Fusion, 160 denier white cordura, twaron roving, 4 oz warp
Sorry, cant post pictures.
The deck is 1.2 oz Cerex under 330 denier Cordura, under 4 oz warp.
Trust me it's beautiful 
Here they are
I’ve been getting some questions about Cordura laminating from some swaylockers via P.M. and through other posts. I’ve been referring everyone to this thread, so I thought I’d bump this one to the top.
Here is a link to the first thread I did on diffeent fibers.
Sorry for my part in the arguing. It got pretty embarassing to look back at it. But there is a ton of information in it. It works.
