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Posted: Fri Jul 02, 2010 7:38 am
by MontuckyMadman
im willing to bet 3 layer of triax and you won't be able to bend that thing especially at your weight.
You said you weight 140 lbs or kilos?
I guess it would be like 300lbs if it was in kilos.
How many stones? HA!
I cant find any modules on that obeche wood. that will have allot to do with the flex.
If you use poplar and maple like your diagram we may be able to attest to the layup, speculatively.
Posted: Fri Jul 02, 2010 7:39 am
by Damon
What do those layers of fiberglass consist of? Bi, tri? Uni? And what weight?
Posted: Fri Jul 02, 2010 11:59 am
by skidesmond
With a total of 4 layers of triax FG it will be like skiing on a 2x4. It won't matter what the turning radius is because it won't bend. And at 140 lbs you won't have chance.
I get that you want to build the perfect ski the first time, but if it was easy everyone would be doing it.
Spend some more time reading the forum to see what others have done.
Just curious, do you have a press already or are you borrowing one?
Posted: Fri Jul 02, 2010 12:26 pm
by dorabito
skidesmond wrote:With a total of 4 layers of triax FG it will be like skiing on a 2x4. It won't matter what the turning radius is because it won't bend. And at 140 lbs you won't have chance.
I get that you want to build the perfect ski the first time, but if it was easy everyone would be doing it.
Spend some more time reading the forum to see what others have done.
Just curious, do you have a press already or are you borrowing one?
Ok I will use only 2 layers of FB under the core and 1 above.
I have been watching this forum for 4 months, even before I became an user.
I have also researched a lot about ski buildings (I have dissected 3 pairs of skis, my old K2 OMNI, an old Dynastar course, an Atomic Race SL 11 and I have seen on a ski shop a dissected Fischer RC4 Worldcup RC).
I also have a lot of exelent material about ski building:
So I don´t think that not enought info will be the problem
About the press, I don´t have it yet (but I don´t even have started building, I am olny working on desing and materials), and as I live in Spain and I think that not much people here have build skis, I will build my own clamp press.
Have a nice snow, Luiz
Posted: Fri Jul 02, 2010 12:31 pm
by dorabito
MontuckyMadman wrote:im willing to bet 3 layer of triax and you won't be able to bend that thing especially at your weight.
You said you weight 140 lbs or kilos?
I guess it would be like 300lbs if it was in kilos.
How many stones? HA!
I cant find any modules on that obeche wood. that will have allot to do with the flex.
If you use poplar and maple like your diagram we may be able to attest to the layup, speculatively.
Hey
The weight was in lbs.
And the final desing of my core uses poplar and maple
About the FB, I will remove one layer from under the core
Posted: Fri Jul 02, 2010 12:37 pm
by dorabito
Damon wrote:What do those layers of fiberglass consist of? Bi, tri? Uni? And what weight?
Hello Damon
I will use 750g/cm2 triaxial fibergalss (
http://www.boardbuildingsupply.eu/produ ... ucts_id=33) once above the core, twice under
Posted: Fri Jul 02, 2010 4:09 pm
by skidesmond
Ok, so you're doing your home work. That's Excellent!! Great start. Keep us posted on your progress.... ski press... ski building... and how they perform when they are done. Looking forward to it.
Progress Update
Posted: Fri Jul 16, 2010 6:54 am
by dorabito
Hey I'm just writing this to tell you that after 2 unsuccessful tries to laminate a wood core (the first had a lot of twist, the 2nd had too much empty spaces), I have finished bonding a 3rd one yesterday. One of them is a little bit curved, and both of them need to be sanded, as they a not perfectly aligned on the base but I'm sure it won't be a problem.
Hope to cut it into shape this week, and bond the ABS sidewalls before the end of the month
Posted: Fri Jul 16, 2010 7:08 am
by skidesmond
Thanks for the update! Post some pics if you can.
Posted: Fri Jul 16, 2010 9:31 am
by dorabito
http://www.freeimagehosting.net/image.p ... 84e0be.jpg
http://www.freeimagehosting.net/image.p ... 2fcd97.jpg
The construction is
poplar/oak/oak/poplar/popla/poplar/oak/oak/poplar
the lamination is the same on both cores, the lighter and darker parts are due to the epoxi shift during the cure
Posted: Fri Jul 16, 2010 10:05 am
by skidesmond
Good progress!
Posted: Fri Jul 16, 2010 11:39 am
by maximegb5
What is the width of your wood stripes?
Posted: Fri Jul 16, 2010 2:51 pm
by dorabito
maximegb5 wrote:What is the width of your wood stripes?
Poplar: 0,9x1,8x200 cm.
Oak: 1x2x200 cm.
Posted: Sun Jul 18, 2010 2:18 am
by OAC
From my book of experience:
A tip (almost a recommendation), regular wood glue is enough for laminating the cores and it's much easier to work with. It "suck" the pieces together, very little dripping and dries quick compare to epoxi. While epoxi forms a "tier" between the wood pieces. Very strong though. So no worries...:-)
When attaching the (flame treated)ABS side walls, use PU(polyurethane) wood glue. Also very easy to work with and bonds excellent with ABS.
Just a tip
Posted: Sun Jul 18, 2010 7:57 am
by skidesmond
OAC - Nice catch on the epoxy.... I didn't pick up on that. Yeah wood glue (I use exterior wood glue) works fine or PU glue.