Applying Carbon fibre sheet above topsheet?

[valsam]

I was wondering if i could apply a carbon fibre sheet somewhat like the F2 conshox on top of my board to give it more stiffnes !

http://cgi.ebay.co.uk/Carbon-Fibre-Sheet-1-8x350x150-mm-100-Carbon-Fiber_W0QQitemZ220265614669QQcmdZViewItemQQptZUK_ToysGames_RadioControlled_JN?hash=item220265614669&_trksid=p3286.c0.m14&_trkparms=72%3A1299%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318

http://cgi.ebay.co.uk/Real-Black-Carbon-Fibre-Sheet-60x30cm-2x2-twill-3M-Boat_W0QQitemZ230306500475QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item230306500475&_trksid=p3286.c0.m14&_trkparms=72%3A1299%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318

I am thinking of cuting it in the shape something like the conshox or the tinkler and opening holes over the binding holes and aplying some adhesive to the rest or just put a self adhesive carbon fibre sheet(the self adhesive sheet is 0,3mm thick while the one with no adhesive is 1,8mm).

Has anyone done this?

[pokkis]

I laminated several layers carbon to my old Madd few years back. Due original butterfly was getting loose and board was too soft in middle.

It worked very well. But no experience by glueing ready made sheet.

My stuff was in middle 2-3 times thicker than original butterfly and it made board quite stiff between bindings which worked then for me well.

There might be picture somewhere on BOL if pic was not linked.

[Jack M]

Sure, that would probably work well. Or you could just buy a Madd...

[bobdea]

I was wondering if i could apply a carbon fibre sheet somewhat like the F2 conshox on top of his board to give it more stiffnes !

http://cgi.ebay.co.uk/Carbon-Fibre-Sheet-1-8x350x150-mm-100-Carbon-Fiber_W0QQitemZ220265614669QQcmdZViewItemQQptZUK_ToysGames_RadioControlled_JN?hash=item220265614669&_trksid=p3286.c0.m14&_trkparms=72%3A1299%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318

http://cgi.ebay.co.uk/Real-Black-Carbon-Fibre-Sheet-60x30cm-2x2-twill-3M-Boat_W0QQitemZ230306500475QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item230306500475&_trksid=p3286.c0.m14&_trkparms=72%3A1299%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1318

I am thinking of cuting it in the shape something like the conshox or the tinkler and opening holes over the binding holes and aplying some adhesive to the rest or just put a self adhesive carbon fibre sheet(the self adhesive sheet is 0,3mm thick while the one with no adhesive is 1,8mm).

Has anyone done this?

I have a sheet laying around that I was going to slap on a board I used to have

I'm lazy and got rid of the board before I got around to it.

try it and tell me how it goes!

[valsam]

Sure, that would probably work well. Or you could just buy a Madd...

I don't think that i can buy a Madd not either the conshox or the tinkler carbon thing for 40euros witch is what the carbon sheet will cost with shipping services +another 10 euros for the adhesive=50 euros=40 $.

I think that the 1,8mm will stiffen the board better (and it's alot cheaper than the one that hase adhesive on it!) but i haven't worked with carbon never and i don't know how hard is it to do the procedure(I mean cutable,flexible,easy to glue).

Realy how thick are the sheets on the conshox or the tinklers or the Madds?

And another thing is what kind of glue to use without ruining the topsheet of the board (it's a new board)if the carbon thing don't work and i wish to take it off!

[eajracing]

I looked at this as an option when I was buildng CF hockey sticks and didn't think it was worthwhile placing it on the top of deck. CF is effectively a bunch of strings and some glue. In tension, it the strings are loaded, but in compression one is effectively "pushing strings" and all you load is the glue (unlike glass fibers, that can take the compressive load). My understanding of it is that when loading a deck, the bottom half is in tension and the top in compression, similar to linear spring, but I have never personally done any modelling to substantiate this.

I'm not denying there would be a noticeable difference by adding sheets to the top of ones deck, but think it would be mostly due to i) changing the overall geometery of the board, i.e. it's stiffer underfoot because it's now thicker underfoot, and ii) the glue/epoxy holding the CF's physical traits as opposed to the actual CF itself.

If anyone has done testing, or modelling I would be interested to know how it works.

Otherwise, it seems like a lot of $$ for CF when a less expensive, more effective alternative could be used.

[Jack M]

I looked at this as an option when I was buildng CF hockey sticks and didn't think it was worthwhile placing it on the top of deck. CF is effectively a bunch of strings and some glue. In tension, it the strings are loaded, but in compression one is effectively "pushing strings" and all you load is the glue (unlike glass fibers, that can take the compressive load). My understanding of it is that when loading a deck, the bottom half is in tension and the top in compression, similar to linear spring, but I have never personally done any modelling to substantiate this.

The CF fibers in a cured sheet will resist out-of-plane displacement, so it is effective in compression too.

I think this will be a neat project. It's basically what Madd does.

[xxguitarist]

I think you would be much better off laminating the CF onto the top of the board with epoxy, rather than gluing a pre-preg sheet onto the top.

[pokkis]

Anyway if you wish to take ever off, it will make permanent marks on board top, or otherwise whole thing is/was not there properly attached and is/was that way useless.

[Hotbeans]

Why not silicone adhesive?

[John Gilmour]

contact vin Q at Out of Bounds snowboards in Killington- have him put you in touch with An American Airlines pilot- Anderson... who has done this to many of his boards- emulating the Madd top sheet.

Then pm me the info because I have a few bords to do here and I don't want to wait for Italian shipping.

________

Ktm 450Exc

[Donek]

Bonding to the topsheet material will be the big issue. You're likely to have a tough time getting epoxy to bond to the surface. Most topsheet materials such as PBT have a scrim backing in order to get the epoxy to stick. Others are sanded and flame treated. A contact adhesive or transfer tape might work with the precure laminate, but that adhesive will be rubber based resulting in a lot of dampening properties and possibly some creap.

Other problems could occur when hot waxing the board. You'll introduce an unbalanced laminate stack which could result in some warping/cupping of the base when you thermally cycle the board. This could make it impossible to base grind in the future and might make it difficult to ride.

[eajracing]

The CF fibers in a cured sheet will resist out-of-plane displacement, so it is effective in compression too.

I think this will be a neat project. It's basically what Madd does.

Does this mean the threads are able to handle compressive forces, or is it still loading the glue/epoxy matrix? I had experience doing fatigue testing on CF rebar developed by a Japanese firm that used a resin to resist out-of-plane displacement - we almost used the stuff to build a-arms for our SAE car - and it always ultimately failed under compression, in the matrix. Despite the ability to prevent the out-of-plane displacement, and the fact the strings were bonded to the matrix, we were still, effectively, 'pushing limp string' and loading the matrix.

Now... this was about 7 years ago - has something changed? Last i heard nano-carbon tubes could handle a compressive load, but it was difficult making one over a few (mu)m long.....??

[Technical.Experience]

I'm working on the same kind of project too. I bought a sheet of 100% carbon fiber and 50% carbon/50% kevlar. Sheets are 1.5 meter per 1 meter. Do not expect that you can just stick that sticky sheet from ebay and it will do the job... Its made to make trims for your car for a fancy looking not to give you the result you want to have. The carbon fiber is a fabric. Until you apply the resin it needs, it will stay soft and moldable like a fabric. I suggest this website to educate yourself about using CF http://www.fibreglast.com/

Ideally, you should do it with many layer of fabric. You have to mold your pattern on the top sheet of the board if you want its camber. Then you bound them with the epoxy/resin that will meet the need of your project (cold/flexibility). Then you cut with a jig saw the pattern you want + a little bit all around. Then you sand to the correct size and it will smooth your previous cut.

Lots of work, lots of time, lots of $ involved. Think about it seriously or buy a Madd like Jack said. But hey, I you are like me and prefer working on project like that instead of watching TV, it is awesome project to do! I'm almost done with my custom made bindings and love the result!

[John Gilmour]

Using stuff that is for cosmetic purposes likely won't offer much benefit. The resin is very important in regards to how boards ride and these pre cured sheets were not designed for snowboarding. Straight out -the resin is likely garbage.

Find Paul Anderson, AKA Emilio Zapatta- a wild cat -and a person IMHO, well worth knowing.

His top sheets worked. And AFAIK there were no long term issues or cupping of the board. They wet laminated with quality resin.

FYI though in a CF 3D top sheet- when base grinding - if you use a lot of pressure in a grind make sure you fit a "Negative" butter fly top sheet in (two triangles) if using lots of weight to get an even grind- and for 95% of grinding you don't have to worry about it- only of you hang on the wheel if you are impatient and trying to remove lots of material in single passes.

I personally have ground over 100 Madd Race Boards on a grindrite (pink stone) with the P-Tex 4000 base... wouldn't wish that kind of work on anyone. Even with production sanders it is miserable work- takes forever and is deafeningly loud even with hearing protection.

________

Mercury villager history

[MUD]

All I will say is, give it a shot! I am not going to tell you you have nothing to loose, you could effectively ruin the board.

READ!!!! As much as you can find.

Take to heart what Sean said, he knows!

West system is the best epoxy readily available to us.

Fiberglast is a GREAT resource.

Skibuilders.com has some great posts, try a search there.

So much for not saying anything.....

[Jack M]

Does this mean the threads are able to handle compressive forces, or is it still loading the glue/epoxy matrix? I had experience doing fatigue testing on CF rebar developed by a Japanese firm that used a resin to resist out-of-plane displacement - we almost used the stuff to build a-arms for our SAE car - and it always ultimately failed under compression, in the matrix. Despite the ability to prevent the out-of-plane displacement, and the fact the strings were bonded to the matrix, we were still, effectively, 'pushing limp string' and loading the matrix.

Now... this was about 7 years ago - has something changed? Last i heard nano-carbon tubes could handle a compressive load, but it was difficult making one over a few (mu)m long.....??

Sounds like you know more than me. I just figured loading CF and fiberglass in compression were basically the same idea. *shrug*

[BadBrad]

Many racecars are made of carbon fiber, including Formula 1 cars chassis and their suspension arms. These suspension arms must take both compressive and tensile loads, so obviously carbon fiber works in compression as well as in tension. Carbon fiber bicycle frames also take loads in compression and in tension.

Now, with tubular structures, like the bicycle frame tubes, one side is usually in compression while the other side is in tension, but even a flat sheet of carbon fiber can withstand loads in multiple directions. Also, a flat sheet of carbon fiber has fibers running in multiple directions so they won't all be in compression when a load is applied.

Be careful working with carbon fiber. It's nasty stuff if it gets into your skin.

[MUD]

Does this mean the threads are able to handle compressive forces, or is it still loading the glue/epoxy matrix? I had experience doing fatigue testing on CF rebar developed by a Japanese firm that used a resin to resist out-of-plane displacement - we almost used the stuff to build a-arms for our SAE car - and it always ultimately failed under compression, in the matrix. Despite the ability to prevent the out-of-plane displacement, and the fact the strings were bonded to the matrix, we were still, effectively, 'pushing limp string' and loading the matrix.

Now... this was about 7 years ago - has something changed? Last i heard nano-carbon tubes could handle a compressive load, but it was difficult making one over a few (mu)m long.....??

We found with the studies I was involved with that if there is too much epoxy in the matrix, the epoxy is what is loaded, not the fibers.

We did compression after impact (the only way we could buckle the plates) with various epoxies and percentages of epoxies. and found that IF the epoxy to fiber ratio is optimal, you get a VERY strong and efficient matrix ultimately loading the fibers.

These results have been put to use in the aerospace industry to build wings.

This is a WAY simplified explanation. I can try to find the papers, but I believe they are proprietary.

[MUD]

One more thing.....

You could vacuum bag it.

LOTS of tape where you do not want epoxy.

Lay the sheet on top (precut) and "put" the whole thing in a bag.

You would have quite a bit of clean-up.

If top sheet is prepared correctly, it would work nicely.

[EnisiWaya]

Do not use West epoxy on your board it is too brittle.

System 3 used to have a test kit to compare their epoxy with others.

System 3 is much less brittle than MAS or west and will stand repeated flexing. Plus it it much less toxic than most. Many restorers used to use west and developed sensitivity problems from it and now use System 3.

all of them can be had wholesale from

http://www.jamestowndistributors.com/userportal/main.do

good luck!

Chase:biggthump

[eajracing]

MUD - thanks - i'd love to see the papers if you ever came across them.. see what i've missed over the last few and why those cervelo guys think they can charge so much for such a gorgeous frame....

As pointed out in a bunch of repsonses - the sheets typically have multiple layups of fibers that handle different loads - it may be that the CF topsheets are best at at handling the torsional stress through the deck than the 'pure' 3-point bending.

and to clarify - i never suggested that CF cannot take a compressive load - it can (through the matrix), but it will never have the strength it can take when loaded in tension (through the CF) - similar to how concrete can typically take 4x the compressive failure load than tensile (hence the addition of rebar) and this always has to be taken into account when designing the part/board/etc. It just seems that if the top of the board is under a compressive load, would it not make more sense, both from an economical and design standpoint, to use a topsheet with better compressive qualities? Or search for this aerospace CF MUD refers to? Is that what Madd uses? Does anyone know if the CF on Madds is for longitudinal or torsional flex?

[MUD]

Do not use West epoxy on your board it is too brittle.

System 3 used to have a test kit to compare their epoxy with others.

System 3 is much less brittle than MAS or west and will stand repeated flexing. Plus it it much less toxic than most. Many restorers used to use west and developed sensitivity problems from it and now use System 3.

all of them can be had wholesale from

http://www.jamestowndistributors.com/userportal/main.do

good luck!

Chase:biggthump

Good too know......

The guys on Skibuilders.com seem to pretty much exclusively use West System.

[valsam]

I am thinking of using the 1,8mm sheet that already consists of an epoxy carbon fibre with the recommended epoxy by the e-bay seller (Stabilit-Express witch i can find easely here in Greece )for gluing it to the top sheet after i sand it a little bit and trying to figure a way of how to keep pressure on the carbon sheet so that it will bond evenly!

[MUD]

I am thinking of using the 1,8mm sheet that already consists of an epoxy carbon fibre with the recommended epoxy by the e-bay seller (Stabilit-Express witch i can find easely here in Greece )for gluing it to the top sheet after i sand it a little bit and trying to figure a way of how to keep pressure on the carbon sheet so that it will bond evenly!

The only issues I can see is it is cured FLAT. Your board is not. It is going to fight your camber and profile and try to flatten the board. PLUS it is going to try and delaminate as the sheet wants to be straight and the camber bent......