Aloha, this is my first post and my first pair. I have been lurking here for quite some time, and can proudly say that I visit this site more than any other (providing I'm not obsessing over a lens). It keeps me going though the summer.
I am planning on building rockered park/pow skis. They will be symmetrical. 148-135-148. 166cm long. I will be laying up with materials from the skibuilders store, with a maple core.
Thats pretty short, but since I am just under 6'' and 120 pounds, I think they will be fine. I also prefer short skis. I might consider going even shorter.
My main inspirations came from the K2 Hellbent, and some of Line's skis.
I have a few questions for everyone...
1. I want them to have pretty soft flex. I want to be able to butter easily. What thickness should the core be to compensate for the wide waist? And how would the rocker affect the flex pattern?
2. How much camber/rocker should I build into the mold? (I'm using a non heated vacuum bag with West Systems epoxy)
3. The radius... I dont want it to be too small because I dont want it to get too squirrelly in the chop. I also want them to be nimble on the hard stuff.
Any ideas?
4. Bamboo stringers and sidewalls. Good idea?
5. Cardboard honeycomb. An idea I have been tossing around since I saw it here a few months ago. I did a test and found it to be strong and lightweight. Perhaps bamboo could be used on the sides and under the binding with a 3"-ish gap down the middle, filled with cardboard.
-Camen
I need advice on a rockered ski...
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
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RudolphTheSkiingReindeer
- Posts: 9
- Joined: Thu Mar 29, 2007 8:41 pm
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RudolphTheSkiingReindeer
- Posts: 9
- Joined: Thu Mar 29, 2007 8:41 pm
In my rush to get everything down I forgot to give most of the specs...
Ski length: 166cm
Ski width: 148-135-148 (I might change it to 148-135-142)
Running length: 71cm
Rocker length (includes tip/tail): 47.5cm
Camber: 9mm
Rocker height: 34mm
Sidecut radius (only under the running length): 10000(mm?) (I really don't know enough to tell what that number will do to the ski. I was just the most pleasing and flowing line in SnoCAD. Please enlighten me.)
-Camen
Ski length: 166cm
Ski width: 148-135-148 (I might change it to 148-135-142)
Running length: 71cm
Rocker length (includes tip/tail): 47.5cm
Camber: 9mm
Rocker height: 34mm
Sidecut radius (only under the running length): 10000(mm?) (I really don't know enough to tell what that number will do to the ski. I was just the most pleasing and flowing line in SnoCAD. Please enlighten me.)
-Camen
i to will be interested in some more information on making a rockered ski. I just picked up a pair of water skis that I will mount bindings on for the deep pow pow, i think it will be super fun in pow because of the reverse sidecut and negative camber but i will have no control elsewhere. if they work good i will try to make a pair sometime.
guess who`s back! hell yeah it`s plywood 
well mags. finally i had some powdays on my rockered ones down south... so i can give you some advise.
first of all.... you said you want a rockered ski. with camber in the middle or flat?
i think there are two ways to get the skis you want. i`m just talking about the camber/stiffness stuff:
first way is to build a ski with pretty much rocker. so a long area of tip and tail get rockered and lifted from the ground. by this the ski become easy to butter just because of the rocker. so you can build them pretty stiff. and you also have to do it stiff, cause otherwise the long rockered areas begin to shatter when riding... and this is crap.
second option: you want a softer ski. so you can`t use that much rocker, because it would get too shattery otherwise.
so i can tell you what i did: i rockered about the first and last 40cm of my skis on a 175fat. it`s great to ski, unless the snow is really icy and hard. then it gets really painful. furthermore i think this is quite a lot of rocker, more wouldn`t make any sense, because it gets really shattery. and it`s also on the border of getting squirelly.
on my next ski i`ll use less rocker, so i think you should get at least a section of 1m of flat/cambered ski in the middle to become something smooth to ride....
but...you`ll always have to try and error.
well mags. finally i had some powdays on my rockered ones down south... so i can give you some advise.
first of all.... you said you want a rockered ski. with camber in the middle or flat?
i think there are two ways to get the skis you want. i`m just talking about the camber/stiffness stuff:
first way is to build a ski with pretty much rocker. so a long area of tip and tail get rockered and lifted from the ground. by this the ski become easy to butter just because of the rocker. so you can build them pretty stiff. and you also have to do it stiff, cause otherwise the long rockered areas begin to shatter when riding... and this is crap.
second option: you want a softer ski. so you can`t use that much rocker, because it would get too shattery otherwise.
so i can tell you what i did: i rockered about the first and last 40cm of my skis on a 175fat. it`s great to ski, unless the snow is really icy and hard. then it gets really painful. furthermore i think this is quite a lot of rocker, more wouldn`t make any sense, because it gets really shattery. and it`s also on the border of getting squirelly.
on my next ski i`ll use less rocker, so i think you should get at least a section of 1m of flat/cambered ski in the middle to become something smooth to ride....
but...you`ll always have to try and error.
plywood freeride industries - go ply, ride wood!
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RudolphTheSkiingReindeer
- Posts: 9
- Joined: Thu Mar 29, 2007 8:41 pm
you want a soft ski basically because a soft ski floats better, do i get you right?
if yes: with rockered skis it`s nearly the same as with skis with fully reverse camber: their special construction adds a little more floating to the thing.
a soft ski with normal camber gets bent "upwards" when floating in pow. but rockered ones are already bent upwards. so they don`t have to be that soft.
on my next rockered pair i try to get a stiff ski. as i said, they float great because they are already bent upwards. by creating a stiffer ski i hope to reduce the vibrations in tip and tail. hopefully stiffer skis perform also better in tracked stuff, i expect a more stable ride, something like that.
but at the same time the cambered section shouldn`t get too stiff. i`m still thinking about how to achieve this.
maybe a special core profile would be a solution...but on my first pair i used a "normal" core profile, as the kams used on a lot of their pairs in the gallery.
i also thought about dampening...but it`s kind of tricky. maybe if you could put some sort of rubber in tip and tail, over the whole width, as long as the rockered parts of the ski. maybe cut away 1mm of the woodcore in tip and tail and replace it with a layer of rubber....
if yes: with rockered skis it`s nearly the same as with skis with fully reverse camber: their special construction adds a little more floating to the thing.
a soft ski with normal camber gets bent "upwards" when floating in pow. but rockered ones are already bent upwards. so they don`t have to be that soft.
on my next rockered pair i try to get a stiff ski. as i said, they float great because they are already bent upwards. by creating a stiffer ski i hope to reduce the vibrations in tip and tail. hopefully stiffer skis perform also better in tracked stuff, i expect a more stable ride, something like that.
but at the same time the cambered section shouldn`t get too stiff. i`m still thinking about how to achieve this.
maybe a special core profile would be a solution...but on my first pair i used a "normal" core profile, as the kams used on a lot of their pairs in the gallery.
i also thought about dampening...but it`s kind of tricky. maybe if you could put some sort of rubber in tip and tail, over the whole width, as long as the rockered parts of the ski. maybe cut away 1mm of the woodcore in tip and tail and replace it with a layer of rubber....
plywood freeride industries - go ply, ride wood!
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RudolphTheSkiingReindeer
- Posts: 9
- Joined: Thu Mar 29, 2007 8:41 pm
I think Im trying something along the lines (no pun intended) of Line's EP pros, but with a little more rocker... and a lot shorter.
I like the idea of camber in the midsection, and longer-than-normal tips and tails. I think that would be good for an all-arounder-ish-pow ski. In other words... I want something I can still use when the minimal powder we get around here gets choppy or turns hard. Maybe a few runs in the park too.
But I also want something a light weight guy like myself wont have to work to throw around in the deep, heavily wooded, steeps (the kind of run I live for).
I think moderately stiff with some rocker or early rise would be good... but a stiff ski for me is probably going to be pretty soft for a full grown adult.
So, for the special core profile... would the thickest parts be near the bent bit of the rockers, with it tapering down in the middle and tips?
What if instead of tapering the middle, you used a longer flat "normal" midsection that would extend out to maybe the middle of the rockered part before tapering to the tips... then milled in "butter zones" or specific places for the core to bend in front and behind the binding area?
Thank for all the feedback you've given me.
-Camen
I like the idea of camber in the midsection, and longer-than-normal tips and tails. I think that would be good for an all-arounder-ish-pow ski. In other words... I want something I can still use when the minimal powder we get around here gets choppy or turns hard. Maybe a few runs in the park too.
But I also want something a light weight guy like myself wont have to work to throw around in the deep, heavily wooded, steeps (the kind of run I live for).
I think moderately stiff with some rocker or early rise would be good... but a stiff ski for me is probably going to be pretty soft for a full grown adult.
So, for the special core profile... would the thickest parts be near the bent bit of the rockers, with it tapering down in the middle and tips?
What if instead of tapering the middle, you used a longer flat "normal" midsection that would extend out to maybe the middle of the rockered part before tapering to the tips... then milled in "butter zones" or specific places for the core to bend in front and behind the binding area?
Thank for all the feedback you've given me.
-Camen
hehe funny, i also had the lines in my mind when i did my pair 
the core profile is somehow difficult... because what you need are stiffer tip and tails, compared to a normal ski. the cambered section has to have same properties as on a normal one. and now for the trickiest part: the transition between normal camber and rocker. this is somehow the key-point because...it`s worth nothing if you just have stiff tip&tails but the transition is somehow weak - then the tips will still start to vibrate.
at least this is what i guess and what i was thinking of for the last week
so i think you`d need a normally profiled core in the middle, normal tapering and flat section in the middle (or which profile ever you`d chose for your normal ski). then i`m not very sure about what to do next: i`ve got two possabilities:
the first would be to stop the tapering just a little bit before the spot where the transition from cambered to rockered begins. there you could create a "flat" spot in the core without tapering. this would result in a stiffer transition and at the same time stiffer tip and tails, because it would shift the tapering in tip and tails to the ends. hope you understand what i`m trying to explain... there is only one problem: i think this way is a bit difficult to build with our backyard equipment...cause you`d need to work very precise...
due to this my second option would be easier to realise: just use a different, flatter tapering for the transition+tip/tail. this could have more or less the same effects as the option above, but could be done easier.
the core profile is somehow difficult... because what you need are stiffer tip and tails, compared to a normal ski. the cambered section has to have same properties as on a normal one. and now for the trickiest part: the transition between normal camber and rocker. this is somehow the key-point because...it`s worth nothing if you just have stiff tip&tails but the transition is somehow weak - then the tips will still start to vibrate.
at least this is what i guess and what i was thinking of for the last week
so i think you`d need a normally profiled core in the middle, normal tapering and flat section in the middle (or which profile ever you`d chose for your normal ski). then i`m not very sure about what to do next: i`ve got two possabilities:
the first would be to stop the tapering just a little bit before the spot where the transition from cambered to rockered begins. there you could create a "flat" spot in the core without tapering. this would result in a stiffer transition and at the same time stiffer tip and tails, because it would shift the tapering in tip and tails to the ends. hope you understand what i`m trying to explain... there is only one problem: i think this way is a bit difficult to build with our backyard equipment...cause you`d need to work very precise...
due to this my second option would be easier to realise: just use a different, flatter tapering for the transition+tip/tail. this could have more or less the same effects as the option above, but could be done easier.
plywood freeride industries - go ply, ride wood!
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RudolphTheSkiingReindeer
- Posts: 9
- Joined: Thu Mar 29, 2007 8:41 pm
I think I got it nicely visualized in my mind.
I think that shouldn't be too difficult. Maybe a bit tricky but definitely doable. (my dad is a professional cabinet maker... so I can use some pretty nifty equipment.)
In the transition from one taper to the other you could sand it down carefully so it has a nice rounded flex. You could also reinforce it with a small piece of fiberglass if you wanted the bent bit to be especially stiff. Would you?.
Also... In a wide ski (more than 140mm), for a person weighing about 120lbs (me), what would the ideal core thickness be?
Sushi's ready... Got to go!
-Camen
I think that shouldn't be too difficult. Maybe a bit tricky but definitely doable. (my dad is a professional cabinet maker... so I can use some pretty nifty equipment.)
In the transition from one taper to the other you could sand it down carefully so it has a nice rounded flex. You could also reinforce it with a small piece of fiberglass if you wanted the bent bit to be especially stiff. Would you?.
Also... In a wide ski (more than 140mm), for a person weighing about 120lbs (me), what would the ideal core thickness be?
Sushi's ready... Got to go!
-Camen