What do you think?
Thanks, Shredder111
Thinking of making all wood skis?
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shredder111
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Thinking of making all wood skis?
You guys know how skateboards are made right? They slap wood veneers together and sandwich it. I was thinking of making myself a pair of skis which had no composite in them except fiberglass cloth. I was thinking of using 8-9 oak or maple veneers 1mm and putting a layer of fiberglass between each one. That would be my set of skis.
What do you think?
Thanks, Shredder111
What do you think?
Thanks, Shredder111
That sounds like a lot of glass unless you are using very light (say 4oz) glass.
This has been done before if you look back at early composite skis. I also remember someone making skis that just had one layer of glass under the core and none above.
Horizontal laminate skis have been successfully made by members of this board - Plywood and Davide I think.
This has been done before if you look back at early composite skis. I also remember someone making skis that just had one layer of glass under the core and none above.
Horizontal laminate skis have been successfully made by members of this board - Plywood and Davide I think.
yep! i did it
i also used 1mm veneer. but i didn`t put any fibreglass between the veneer.
putting fibreglass between the sheets has "no" effect on a ski. let me explain:
the whole thing works like skis with vertical core. it`s a sandwich construction which means that you`re using something as a core. the main goal of the core is to get a distance between the top and the bottom layer of composites. the core just "guides" the incoming forces to the outside where the composite layers take the load. by doing so you get the most effective transmission because you can use all the advantage of the different attributes of the materials you`re using.
by putting some composite layers in between the veneer you reduce this effect: in the middle of the core the load isn`t that big as on the outside of it. by putting some composites in the middle you add the same weight as if you`d put them on the outside - but the composites just can take a smaller load.
of course a ski with veneer as you plan to build it would work. but it would be heavier and the composites wouldn`t be that helpful as they are ment to be.
i also used 1mm veneer. but i didn`t put any fibreglass between the veneer.
putting fibreglass between the sheets has "no" effect on a ski. let me explain:
the whole thing works like skis with vertical core. it`s a sandwich construction which means that you`re using something as a core. the main goal of the core is to get a distance between the top and the bottom layer of composites. the core just "guides" the incoming forces to the outside where the composite layers take the load. by doing so you get the most effective transmission because you can use all the advantage of the different attributes of the materials you`re using.
by putting some composite layers in between the veneer you reduce this effect: in the middle of the core the load isn`t that big as on the outside of it. by putting some composites in the middle you add the same weight as if you`d put them on the outside - but the composites just can take a smaller load.
of course a ski with veneer as you plan to build it would work. but it would be heavier and the composites wouldn`t be that helpful as they are ment to be.
plywood freeride industries - go ply, ride wood!
All wood ski
I made an all wood ski sandwiching horizontal layers. It is increadibly forgiving & soft but feels dead. More camber would help with this. It has 8mm but I would double that. For fiber reinforcements, I would apply C.F. just under the base (tension) and Fiberglass to the top (compression) this should be an excellent combination.
Carbon Fiber on the bottom, in tension, is really a waste of the material. C.F. is much better in compression than tension. If you want to get some life and pop to you skis, especially with an increase in camber, put your C.F. on the top side of the core. Glass is about the same in tension and compression.
Really for my $0.02, get rid of the C.F. entirely and work on engineering your core-that is where your fundamental structural properties react. For all the tech b.s. the big companies throw out as marketing ploys, building skis is not exactly on the same level as shooting monkeys into space like Volkl, Rossi, etc. would like you to think. Small changes, 1mm in thickness and small profile ramp changes, make large differences in your ski's performance. --Geoff
Really for my $0.02, get rid of the C.F. entirely and work on engineering your core-that is where your fundamental structural properties react. For all the tech b.s. the big companies throw out as marketing ploys, building skis is not exactly on the same level as shooting monkeys into space like Volkl, Rossi, etc. would like you to think. Small changes, 1mm in thickness and small profile ramp changes, make large differences in your ski's performance. --Geoff
carbon fiber
I agree that your core profile/thickness and materials is the most important. However, all the sources that I have seen say that carbon fiber is stong in tension, and worthless in compression. My own experimenting confirms this, and I have seen bow makers use it to back the bow (tension) and fiberglass the belly (compression).
-mikkelsen
-mikkelsen
Mikkelsen is right.
Stregth of carbon fiber in compression is about the half than in tension, but Young modulus (stiffeness) is about the same. Carbon placed above the core will break easily.
http://www.torayca.com/techref/en/images/comp02.html
Since few years, special carbon fibers with high compressive strength are available (pitch low modulus). If you manage to get them, they can be used as top layer.
Stregth of carbon fiber in compression is about the half than in tension, but Young modulus (stiffeness) is about the same. Carbon placed above the core will break easily.
http://www.torayca.com/techref/en/images/comp02.html
Since few years, special carbon fibers with high compressive strength are available (pitch low modulus). If you manage to get them, they can be used as top layer.