Ski Builders Forum

Sollar composites has triax carbon in stock. I thought it was worth mentioning as I've seen guys on here wanting too build all carbon skis. I have myself used a 0/90 8 ounce biax carbon with great success in a couple snowboards.

But skiers....diagonal fibers.... Blah.blah.blah.

anyway, it's a 0/60/60. it's twill braided. 15.2 ounce/yard.
Probably be able to thin out your cores and come up with a nice lightweight
Product if someone wanted to experiment. It's pricey. Though I will say John has a great operation with some overall great deals.

but it is twill braided

Yes, what's your opinion on braided comps? I know that the fiber layout is the same in all directions, but is there anything else that makes braided unsuitable?

We ordered some triax from them six weeks ago or so and they just contacted us last week saying that their supplier never sent them any.

I don't know which fabric you were pointing towards exactly, but that not so important:

Inter-lock your fingers (left and right hand) and push down on the table. It should give you a good idea why twill is not ideal. The inter-locking will represents plain weave - but it makes the point.

http://www.netcomposites.com/guide/woven-fabrics/40

If you are using this with the sitka spruce, then you will need to be on top of the composite side of this design, as carbon and glass have different failure modes. Glass will give you a 'head's up', whereas carbon is less likely to do that for you.

This is broad brush, you understand; but if you are back country, this stuff may suddenly become important. A best next step might seen you concentrating on optimising your fibre volume fraction.

The above site can help you with this:

http://www.netcomposites.com/calculator ... -fractions

Building a fiber impregnator is quite straight forward.

so after looking at the above links I can only guess that twill, braided, and those other styles are good choices for a product that is not bending or flexing as part of its job.

Unlike skis and boards which are flexing all the time. I have used an 8 ounce carbon biax this season. 0/90. 0 on one side, 90 on the other. I used a bamboo core with my regular profile. I also used a bamboo veneer for the topsheet. the board came out nice and stiff. After riding the piss out of it, trying to brake it, I decided carbon kicks ass.

I did take it to the next step and flexed the shit out of it with my foot between the bindings while pullin on the nose. I got some cracking sounds. Bamboo does not make that sound, it was fibers breaking.

From this I decided that a full carbon snowboard should be a stiff ride by design, one that does not allow the board to flex a whole lot like a park noodle while riding. as we all know by know - carbon is stiff but brittle.

Good skis are always stiffer, So no mention there

I never intend to use a twill or braided fabic anyway, but if you could sum up in idiot terms of why you would not want to use it in a ski. I would love to hear it. tried to brake my finger while they were interlocked, but all I did was make my bummed shoulder hurt. I think I was somewhere on the right path with fibers interlocked with fiber not being good when flexed, but let me hear it.

when you mention the Sitka and the backcountry, Im lost. Unless you meant that a light fabric and a soft wood being a setup for a complete breaking failure, and bootpacking in waist deep powder sucks.

look forward to hearing more.

Cross linking your fingers and applying pressure should gives a sense of the effects of 'crimp'. 'Crimp' is something you can reseach and form a view on how damaging this effect could be to your design. You may decide you can carry this issue and priorities your understanding the effects of modulus and weight of the fabric. If your design is focused on being super light, then you might decide not to carry this issue.

Searching 'advantages of non-crimp fabrics' will bring up quite a few articles.

Essentially, it comes down to how much bootpacking you are happy to do )

It would be good to have a more in-depth discussion on various aspects of the build process, focusing on the finite detail based on research papers and net resources etc.

http://www.netcomposites.com/guide/spre ... abrics/118

The lower mechanical performance of traditional woven reinforcement fabrics can be attributed to crimp angle and crimp frequency due to use of tows which are comparatively narrower and thicker than the STT. These factors, which adversely affect the performance of a woven material for composites applications, are significantly reduced by weaving STT as warps and wefts into an STF