Laying Carbon Fiber

[MAMBA2200]

What is the best thing to use to lay CF cloth in your boat would the Z-Poxy work good or would i need to thin it out with alcohol

[Rocstar]

Z-Poxy works, a little brittle though. I switched to West System's 105 with 207 clear hardener, great stuff to work with.

[MAMBA2200]

Where can u get that stuff?

Sent from my FE Phone

[bracka69]

West Marine is a dealer for West System products.

[Rocstar]

105 Resin

http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=14925&catalogId=10001&langId=-1&storeId=11151&storeNum=50218&subdeptNum=50219&classNum=50220#.US56mzDvsmM

207 Hardener

http://www.westmarine.com/webapp/wcs/stores/servlet/Product_11151_10001_14894_-1?ci_src=14110944&ci_sku=14894&cid=sc_googlepla&gclid=CJXe19G217UCFa9aMgod9wMAIw#.US56hjDvsmM

[bracka69]

Hey Rocstar22 any particular reason for using the 207 hardener over say the 206? Does the 207 really have a noticeable amber color to it once applied or does it dry fairly clear? Planning on doing an inlay myself using west system.
Thanks

[Rocstar]

Hey Rocstar22 any particular reason for using the 207 hardener over say the 206? Does the 207 really have a noticeable amber color to it once applied or does it dry fairly clear? Planning on doing an inlay myself using west system.
Thanks

Never used the 206 so I can't say, I'm sure some guys here have. I just went with the 207 for inlays because it is clear. I use G/Flex for everything else.

[bracka69]

Ok Thanks

[Fluid]

Z-poxy finishing resin works great. It is NOT too brittle at all, but like all carbon overlays you only want enough resin to soak the cloth. You do not want it to puddle on the surface. I have crashed cats with carbon I installed at over 90 mph with no cracking, etc. Z-poxy is a lot easier to use and cheaper for small volumes than West. But West is certainly a wonderful product.




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[iridebikes247]

As Fluid said only enough to soak the carbon. It is easy to go overboard and a little goes a long way. I use West Systems epoxy and the stuff is awesome but you must buy a large quantity as it is made for full size marine applications. Expensive but if you're into FE for awhile I say go for it, also you can get fillers that make sanding and body work very very easy.

[Rocstar]

Z-poxy finishing resin works great. It is NOT too brittle at all, but like all carbon overlays you only want enough resin to soak the cloth. You do not want it to puddle on the surface. I have crashed cats with carbon I installed at over 90 mph with no cracking, etc. Z-poxy is a lot easier to use and cheaper for small volumes than West. But West is certainly a wonderful product..

I have used Z-poxy for inlays on several hulls, and it's a "Good" product. However with the amount that I use, the West Systems is a better fit and in my opinion, a better product.

[larryrose11]

I have used zPoxy and West 105/207 and the west systems is superior. It is much harder, but tough too, not brittle.

As for the CF fabric inlay, the key to making it stronger but not much heavier is to get good contact between the CF cloth, and the base. CF cloth moves on its own if you just wet it and lay it in. Everyone that works with CF cloth for a living will tell ya that it is critical that you squeeze all the extra epoxy out. I have been through this before, and I came up with a way that works. YOu need to get a material called peel-ply. It is a Teflon impregnated fabric that when pressed against the CF cloth, will let the extra epoxy bleed through. After the epoxy is cured, the peel-ply can be peeled off. It will leave the CF dull, but that is fixed with a thin layer of epoxy painted on, and wiped down. Cures nice and shiny.

The basic goal is to squeeze the CF cloth against the hull, held in place with pressure. YOu can also use a traditional vacuum bag, but most don't have access to those.
I lay down CF cloth layers, wetted with west epoxy, and put on a layer of peel-ply, a layer or two of paper towel to absorb the extra epoxy that will bleed through. I will hold all this in place with blocks of foam that have been cut to fit in the hull. Packaging foam works well. It is squishy and will conform to the curves of the hull. I will then use a block of wood on the top to serve as base for a clamp. The hull my need to be supported from underneath with foam as well. Once this is all assembled, place on your workbench, with the wood on the top. Put the squish on it with some c-clamps. Once it is cured after a day, you will see that about 1/2 of the epoxy bled thru the peel-ply, absorbed in the paper towel. The structure will now be quite tough.
I typically use 3 layers of 4oz cloth for reinforcing a hull.
To give you an idea of thickness, 5 layers of 4oz cloth compressed will make plate about 0.75 mm thick. triple that and you have some hefty stock for motor mounts and the like.
As for CF fabric stock, I really like Soller. Their CF fabric has a light adhesive built in that prevents fraying. Quite nice stuff

http://www.solarcomposites.com/

[Richie the shipwright]

Yep, larry is 100% correct, Too much resin is bad practice. The resin to fiber ratio has an effect on both strength and weight. Most woven cloth has a 1-1 ratio when wet out correctly. EG- 1KG of resin to 1KG fiber. With vacuum bagging you can achieve ratios as low as .35 to 1. (350gams resin 1KG fiber).
Glad you bought up peel ply too, its really great stuff but can be expensive. Ive been using an alternative fabric called "bemsilk" from the local spotlight fabric shop. Seems to work well and is much cheaper than peelply. :-)

[larryrose11]

Thanks for backing me up Richie. A lot of people on here just lay the CF down with no clamping or peel ply. It may work, It may bridge the corners, but it will be heavy. I learned the lesson of weight on riggers, where I looked at every gram of weight.

Peel ply dosn't have to be expensive. The stuff I use is pretty cheap, this is about $6 for 60x36 inches.

http://www.carbonfiberglass.com/Vacuum-Bagging-VARTM-Infusion-Materials/peel-ply-ptfe-release-film/Peel-Ply-Release-Fabric-60-width.html

Also, I prefer to use multiple layers of thine material, than 1 layer of something thick. This is because with multiple layers, you can alternate the directions of the fiber. like a 0/90deg layer, then a 45/45 layer. This will achieve strength in multiple directions.

As for epoxy, it is in these situations where West systems shines because of the long cure times of the (special cleear) 207 hardener and its low viscosity. It takes a some time to wet everything out, assembly the layers and peel ply, foam blocks to finally put the squish on it. During this time, the epoxy is reacting, becoming thicker, preventing the excess from flowing when squished.

[Fluid]

OTOH, for 95% of those reading this thread who want to lay carbon fiber in just one or two of their hulls - Z-Poxy with no vacuum bag or compression works just fine. A 36" catamaran does not worry about an extra couple ounces of resin and most do it largely for looks anyway. Sure not as good as West and a bag (which I have used) but adequate for a non-aerospace application.

There was a thread a few months ago where "experts" said that if you don't use a vacuum bag etc. that carbon fiber will not even stiffen a hull. Totally ridiculous and anyone who has laid carbon knows better.....




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