Fiberless skis
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Fiberless skis
Hi all
Aitor I'm from Spain, so please sorry my English, I may not explain it right or I may not understand his explanations.
Usually I build my own wooden surfboards, and I found this forum and I decided to make my own skis, by the way this forum is so good, congratulations.
But since I'm trying not to use the fiber in my surfboard and I would do the same with the skis. So I asked about the wooden skis made ​​with no fiber, wood and perhaps only the edges of the base metal and Ptex.
The construction technique is a multilayer sandwich plate diferents timber, placed in different directions and glued with poly-or glue.
I know these skis may not have the same quality as a standard ski, flexibility, torsion, and weight, and I think it might be a good ski powder snow, maybe not so good for hard pack skiing, but its interesting the research for environmental protection, using only wood, metal glue, and some plastic.
I found a craftsman in France, Jean Louis Tardy who builds wooden skis, and the truth is that look great.
What do you think about it?, I searched through the forum comments about this but have not found anything.
Aitor I'm from Spain, so please sorry my English, I may not explain it right or I may not understand his explanations.
Usually I build my own wooden surfboards, and I found this forum and I decided to make my own skis, by the way this forum is so good, congratulations.
But since I'm trying not to use the fiber in my surfboard and I would do the same with the skis. So I asked about the wooden skis made ​​with no fiber, wood and perhaps only the edges of the base metal and Ptex.
The construction technique is a multilayer sandwich plate diferents timber, placed in different directions and glued with poly-or glue.
I know these skis may not have the same quality as a standard ski, flexibility, torsion, and weight, and I think it might be a good ski powder snow, maybe not so good for hard pack skiing, but its interesting the research for environmental protection, using only wood, metal glue, and some plastic.
I found a craftsman in France, Jean Louis Tardy who builds wooden skis, and the truth is that look great.
What do you think about it?, I searched through the forum comments about this but have not found anything.
Hepp veguis
I have been skiing on these for the last couple of winters.
http://www.tegsnas.com/ehandelskidor
Belive that they are made of 100 % wood. But these are for touring, not downhill.
A woodcore with veneers instead of fiberglas could work I guess. Natures own carbon fiber!
try it and write about it.
I have been skiing on these for the last couple of winters.
http://www.tegsnas.com/ehandelskidor
Belive that they are made of 100 % wood. But these are for touring, not downhill.
A woodcore with veneers instead of fiberglas could work I guess. Natures own carbon fiber!
try it and write about it.
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An all wood ski does work. I've made a couple pair and really like them. The skis I made are all mountain skis. The ski is great in most conditions. On real hard park I got some chatter because there's no damping material. I'm working on that problem and will post here when I resolve it.
I did a write on my blog this past season. Here's the link, go to the bottom for a critique of the all wood ski.
http://desmondcustomskis.blogspot.com/2 ... -made.html
I also posted info here at skibuilders about the all wood ski
http://www.skibuilders.com/phpBB2/viewt ... c&start=15.
I did a write on my blog this past season. Here's the link, go to the bottom for a critique of the all wood ski.
http://desmondcustomskis.blogspot.com/2 ... -made.html
I also posted info here at skibuilders about the all wood ski
http://www.skibuilders.com/phpBB2/viewt ... c&start=15.
I was looking for that post but couldn't find it. figured it would appear in a couple of posts if this tread started running.I also posted info here at skibuilders about the all wood ski
http://www.skibuilders.com/phpBB2/viewt ... c&start=15.
Finally i am doing a pair of wooden skis, but using only wood. So i will use a combination of bamboo layers instead of the triaxial fiber glass, the bamboo layer is 0,6 mm thickness, 2 layers 0º, 1 layer 45º and 1 layer -45º.
I do not know if I can do this simple reasoning, the fiber glass has a young modulus of 72 MPA and the bamboo 20 MPA, the fiber glass is 0,3 mm thickness , so if i use a combination of bamboo layers 3,5 times thicker could work like the fiber glass. What do you think?
4 layers , 2 of 0º, 1 of 45º and 1 of 45º, the total thickness is 2,4 mm, with the last reasoning the thickness needed should be 1,05 but the minimum thickness is 0,6 mm, maybe i could use just 1 layer 0º instead of 2 (that is a copy of the FB, 50% 0º +25% 45º+25% -45º).
I would like to use the Bambi´s spreadsheet to predict the ski flex. I change some settings, 50 oz/square yard in fabric weight, 1 on volume ratio, 700 kg density, young modulus axial 20 MPA, lateral Young Modulus is 2 MPA.
I think that the volume ratio would be 1 because wood is pure fiber and i use a value for the lateral young modulus of 2 MPA that i found online, but i am not sure that the final young modulus it is ok
What is your opinion?
I do not know if I can do this simple reasoning, the fiber glass has a young modulus of 72 MPA and the bamboo 20 MPA, the fiber glass is 0,3 mm thickness , so if i use a combination of bamboo layers 3,5 times thicker could work like the fiber glass. What do you think?
4 layers , 2 of 0º, 1 of 45º and 1 of 45º, the total thickness is 2,4 mm, with the last reasoning the thickness needed should be 1,05 but the minimum thickness is 0,6 mm, maybe i could use just 1 layer 0º instead of 2 (that is a copy of the FB, 50% 0º +25% 45º+25% -45º).
I would like to use the Bambi´s spreadsheet to predict the ski flex. I change some settings, 50 oz/square yard in fabric weight, 1 on volume ratio, 700 kg density, young modulus axial 20 MPA, lateral Young Modulus is 2 MPA.
I think that the volume ratio would be 1 because wood is pure fiber and i use a value for the lateral young modulus of 2 MPA that i found online, but i am not sure that the final young modulus it is ok
What is your opinion?
So basically you are making triaxial bamboo plywood?
Fighting gravity on a daily basis
www.Whiteroomcustomskis.com
www.Whiteroomcustomskis.com
That's right Vinman, triaxial bamboo plywood instead of triaxial fiberglass.
The triaxial FB thickness of a typical 22 oz fabric is 1mm, 0,7 mm FB + 0,3 mm resin, i think the resin is neglibible for calculation, so the real thickness is 0, 7 mm and Young Modulus of 72 MPA.
The triaxial Bamboo Plywood (aka BP) thickness is 2,4 mm , and YM of 20 MPA.
The density of FB is 2500 kg/m3 and BP 700 kg/m3.
So FB 0,7x72=20,4 MPA, BP 2,4x20=48 MPA, nearly the same resistance.
But not the weight, FB 1x2500=2500 Kg , BP 2,4x700=1680 kg, really lighter.
I know that the units are no ok, but i think the reasoning is clear.
And the combination of layers make the BP very resistant to tearing.
That´s my reasoning , but maybe it´s too simple and i am wrong or maybe forgetting something.
Only the first pair of skis can get me out of doubt
The triaxial FB thickness of a typical 22 oz fabric is 1mm, 0,7 mm FB + 0,3 mm resin, i think the resin is neglibible for calculation, so the real thickness is 0, 7 mm and Young Modulus of 72 MPA.
The triaxial Bamboo Plywood (aka BP) thickness is 2,4 mm , and YM of 20 MPA.
The density of FB is 2500 kg/m3 and BP 700 kg/m3.
So FB 0,7x72=20,4 MPA, BP 2,4x20=48 MPA, nearly the same resistance.
But not the weight, FB 1x2500=2500 Kg , BP 2,4x700=1680 kg, really lighter.
I know that the units are no ok, but i think the reasoning is clear.
And the combination of layers make the BP very resistant to tearing.
That´s my reasoning , but maybe it´s too simple and i am wrong or maybe forgetting something.
Only the first pair of skis can get me out of doubt
Finally i have decided to reply the icelantic scout skis, but instead camber i will build the skis with full rocker.
Short, fat, full rockered, good floatation, and plenty of fun.
The skis measurements 1473 length, 1100 running length, 140-110-130 width, 210 nose length, 163 tail length, sidecut radius 12000, nose anf tail height 46.
![Image](http://woodsurfboard.org/wp-content/uploads/2011/12/scout_reg-copy.jpg)
Short, fat, full rockered, good floatation, and plenty of fun.
The skis measurements 1473 length, 1100 running length, 140-110-130 width, 210 nose length, 163 tail length, sidecut radius 12000, nose anf tail height 46.
![Image](http://woodsurfboard.org/wp-content/uploads/2011/12/scout_reg-copy.jpg)
letting me hang like that??!
Pleasantly reading along eating my dinner then suddenly stop! Last post dec 2012 ![Sad :(](./images/smilies/icon_sad.gif)
How did it go?
Cool project![Smile :)](./images/smilies/icon_smile.gif)
![Sad :(](./images/smilies/icon_sad.gif)
How did it go?
Cool project
![Smile :)](./images/smilies/icon_smile.gif)
Hi Halfdan
Last year i became father (the very best project ever) , so my projects were slowed but not stopped, i finished my press, i am testing glues, especially between the wood and the base, i have tried with polyurethane glue but does not work well, i will try with epoxy glue, not epoxy resin.
I discover that the bamboo layers are not as stiff than the solid bambu, maybe the cut system, the unrolled wood is less stiff, i did a test, i glued 10 bamboo layers of 0,5 mm thickness , and compare with a 5 mm piece of solid bamboo, and upssss, it bend easier , much easier, so i am redesigning the sandwich, maybe i increase the total thickness, or maybe i will cut 1 mm layers of solid bamboo.
Thanks for your good words.
Last year i became father (the very best project ever) , so my projects were slowed but not stopped, i finished my press, i am testing glues, especially between the wood and the base, i have tried with polyurethane glue but does not work well, i will try with epoxy glue, not epoxy resin.
I discover that the bamboo layers are not as stiff than the solid bambu, maybe the cut system, the unrolled wood is less stiff, i did a test, i glued 10 bamboo layers of 0,5 mm thickness , and compare with a 5 mm piece of solid bamboo, and upssss, it bend easier , much easier, so i am redesigning the sandwich, maybe i increase the total thickness, or maybe i will cut 1 mm layers of solid bamboo.
Thanks for your good words.