Ski Builders Forum

I am building some experimental skis using Flax to replace the fibreglass. It is industrial flax specifically designed to replace fibreglass in structural applications.

The flax



It looks like and apart from the surface feel, feels like aero grade glass I have used in the past. But unlike glass doesn't come with the recommendations about gloves for those with sensitive skin.

To cut however is a little strange



My normal glass cutting scissors, the blue handled ones really don't work, even tough they are great on 750gsm (22oz) triax. But the kitchen type ones with orange handles work fine?

Before building skis I know I need to do a bit of testing and calculating. The first round of calculating, pre test is here

Wetting out the samples



Biax (+45/-45) and uni, a double layer of both and single and double layers of triax for comparison



After pressing at 40psi 25C for 24hrs

Thickness measured 10 times with digital callipers with a resolution of 0.01mm average thickness shown

Thickness Glass .62mm

Double glass 1.15mm

Flax 1.1mm

Double flax 2.07mm

Interesting stuff. How does the weight compare to FG? How does the flax compare in cost to FG?

skidesmond wrote:Interesting stuff. How does the weight compare to FG? How does the flax compare in cost to FG?

Weight of the flax is best explained here http://bcomp.ch/files/amplitex-noncrimp ... sh_web.pdf

Cost, compared to aero grade glass http://shop.r-g.de/en/Glass/Non-crimp-fabric-NCF/ it's expensive.

Compared to standard 750gsm (22oz/y) triax it's very expensive - but if it works it is the future

Thought I'd resurrect this thread.

I'm looking to reduce the environmental impact on the skis I make also.

I bought 50 meters of biax flax from Bcomp of Switzerland. I plan on using flax in place of FG as well as add a bit of carbon fiber to keep the ski light and add some umph ( ie pop, but I hate that overly used word). The price seemed reasonable, 3.50 euro a meter (310mm wide) plus 50 euros to ship to the states (Mass.). The kicker is they would only take payment with a wire/bank transfer. Not sure is if this is the only way they take payments or just out of the country purchases, but my bank charged me $40 for the wire transfer

I'll also be using CF in the skis. I know CF isn't exactly environmentally friendly but I think the skis may need some umpf (ie pop, but I hate that word) since flax is a damp material.

As Idris stated the material cuts better with scissors. I have a rotary knife and it would not cut it, blade could be dull. I used Cutco scissors.

The flax seems to soak the epoxy faster than your typical FG will and the flax seems a bit stretchy. But it does wet out OK.

I have 3 test layups in progress.

Material List:
All material was cut to approx 3in x 36in (76mm x 914mm)
biaxial flax 350 gsm (10.3oz)
biaxial flax thickness .7mm
Uni CF 9.4oz (320gsm +/-)
Uni CF thickness .36mm
Poplar veneer 1/16in (1.6mm)
Resin Research epoxy (will have to make the switch to Entropy soon)

sample 1: flax, 2 - poplar veneer, flax
sample 2: CF, flax, 2 - poplar veneer, flax, CF
sample 3: 2 - flax, 2 - poplar veneer, 2 - flax

Sample 3 is being pressed as we speak. When it's done I'll start testing with it and post results here, hopefully in the next week or so.

Des... I'll be watching this,
just curious to see how this pans out.
I've got 150m of triax before I can go "green"

sam

Good to see you guys doing the tests...he he

I have a roll of flax Biax 300g.
The reason I bought it was the text:
"...When pressure is applied during processing, the fibres of the rovings are further spread, filling the open space between the rovings of the fabric. In addition, the low twist results in a great alignment of the fibres, increasing the strength of the final composite part by 10-20% vs. a part made from standard flax yarn...."

It will come on the next ski(s)

Hi,

am interested in flax also - just like the idea of using regrowing materials.
How much is the qm² in the US? Here in Germany its quite expensive, about 30-40€ per qm²....

The material is 350gm. I haven't found a supplier in the US. Bcomp is the only place I found that makes flax in a biaxial weave. It's sold by the square meter. It's 3.5 euros a meter. It measures 310mm wide (about 12inches).

Why not try the basalt material. It is 100% natural.

I got some ~700gms , quadaxial. Its very similar to glass.

Why did you choose the 700g quadrax over the 700g triax basalt that is available?

I've used both. The quad and tri basalt. 19.9 ounce quad and 21 ounce tri. The material rocks. No pun intended. The quad was in a splitboard to create more tortional stiffenes. Tri in a standard board and lots of our skis. The tri had and even amount of fibers in all directions. So again great torsional stiffness.Quad I'm not sure about the fiber breakdown. That splitboard carved on groomers like crazy. Blew my mind. The standard deck did too , with the triax. I'd say there is no right or wrong. I build one split for a guy, went quad on bottom and tri on top. Once again, great flex, carved hard. Not that carving is that important in a split, but it shows tortional stiffness. That is important in a split, as it harder to achieve when the boards 2 pieces. Anywho. If I was doing freestyle, park decks, I'd wouldn't reach for quad first, neither in skis.

The main advantage of flax is its ratio stiffness per weight. As stiffness is about the same as glass fiber, but at half the density, its about double as good as glass. So I would use flax where ever a ski is designed for rigidity - so for torsion then.

And basalt is as natural as fiber glass. They just played well in therms of marketing, but as glass it is molten sand. So very energy consuming and in the CO2 balance is horrible. Flax needs very little water and no pesticides.

But to stay realistic, I use flax for its interesting mechanical properties, as damping and stiffness. Because the green aspect gets a little lost if you laminate it with an epoxy. Even with a "green" one. Because the percentage of green components in those epoxys is around 20% and it still is an epoxy which can't be recycled.
Of course, you have to start somewhere and its better than nothing. But ski building is not yet where it should be...

cool, thanks for sharing. Keep it up, looking forward to read more.

@Chris: I used quadax basalt as I could not at the time get tri. but I built kiteboards so it was ok.

Another source of flax is http://compositesevolution.com. I got some samples last year and did a longboard, worked well. My experience was that it took much more epoxy then glass, most likely due to more air gaps in the material (density).

True, flax does seems to use more resin as I found out in my last sample. Visually, when you lay down the epoxy it begins to soak into the fabric before you can begin to spread it out. With triax FG the resin will sit on top allowing you ample time to spread it out. Eventually when it gets under pressure the epoxy will find it's way.

As for basalt and my limited knowledge of it, it is a natural resource (rock) but requires some serious processing and heat to make into a thin strand and then weave it. Calling it green is a stretch in my opinion but calling it "natural resource" is probably better.

I contacted compositesevolution.com a few times for a sample of the 600gsm but got no replies. I wondered if they buy it from Bcomp but I didn't see 600gsm on Bcomps site.

Food for thought, even if a ski is 100% green how recyclable is it when it's reached it's end of life? There's always ski chairs to be made and other inventive re-uses. I guess it more re-usable than recyclable.

I did read an article about a company in Utah that was collecting old equipment and chipping them into confetti.

http://recycleutah.org/ski_equipment.html

http://recycleutah.org/UserFiles/Fall%2 ... 011(1).pdf

Too lazy to re-type my results here. But I have them on my blog. This is by no means the definitive word on flax but it looks very promising and I will be using it to make skis this winter.

http://desmondskiworks.com/flax-part2/