yo, you guys read this guys techniques and core layup?
the stagger
http://exoticskis.com/forum/Default.aspx?g=posts&t=98
not really my type of ski but I found it interesting
summer 08
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MontuckyMadman
- Posts: 2395
- Joined: Fri Jun 20, 2008 9:41 pm
about the grafics etc: i tried several things.
in general if you use a wooden topsheet it can happen that the veneer soakes up epoxy during layup/pressing/curing. this happend on all of these 3 pairs. at the end there are "dry" areas on the topsheet and there are areas that got soaked through with epoxy and therefore are "wet". because they got wet on those areas the wood looks different, mostly darker.
on the alberich i did following: after pressing i coated the whole topsheet with epoxy so that even the dry areas got wet. i mixed the epoxy with methanol so that the epoxy got really really liquid and got soaked in easier by the wood. i let everything cure and then sanded off the remaining epoxy on the top of the wood until there only remained "epoxy soaked wood". this resulted in a pretty hard, though looking, shiny surface. then i sprayed on the pitchfork grafics with stencil print and aerosole spray colour and added an other layer of thin spray varnish.
this method involved a lot of sanding and needs quite some time...sanding, epoxy, sanding, varnish....eeew!
therefore i tried to find a faster way of doing topsheets. this is what i did on the mimir:
as the skis came out of the press the veneer showed those dry and wet areas too. i just sanded the veneer and coated it with marine coating (this stuff is called coelan and is said to be a little elastic). you might be able to see it on the picture i posted earlier: the ski on the left looks not that good... because i applied a pretty thick layer of this coating/varnish it was nearly impossible to get an even, nice and clean looking surface. the pair on the right looks better, but still i`m not that satisfied.
so in general:
the epoxy-spray varnish-method creates a smoother surface because there is nearly no coating on the top of the wood. the "coating" all got soaked in by the wood. because the wood is (hopefully) fully soaked with epoxy it gets heavier, but also stronger and tougher. all in all the result is a pretty hard topsheet.
the marine-coating-method is a little quicker. if you can spray on this coating you`ll get a smooth surface too. the downside: there is a relatively soft coating on top of soft wood (because the wood itself is not that tough and hard and even thou it gets soaked with coating this coating is never as strong as epoxy). this surface is more likely to get damaged by the steel edges than the epoxy-method. the edges just cut through the coating and hurt the wood so that there is dry wood exposed - BAD!
i didn`t ski the epoxy-method-ski much so they don`t show much abuse, therefore i can`t tell you for sure if the epoxe-method withstands abuse better. but i`ve got the feeling it does. at least there is no dry wood exposed when hitting the topsheet because the wood mostly got soaked by epoxy.
hope this helped a little...
the wood is european walnut, 0.9mm thick (there was no thinner veneer so i had to take this. maybe thinner veneer would reduce the problem because it might get fully soaked with epoxy during pressing and therefore you could save one step on the epoxy method).
rocker sections expressed as a radius.... ew! tip and tail rise for about 20cm to a height of 45mm. so i guess the radius is about 40cm or so? as those were built mainly for slope & park skiing i did a "narrow" tip radius as i didn`t want long tip and tails.
in general if you use a wooden topsheet it can happen that the veneer soakes up epoxy during layup/pressing/curing. this happend on all of these 3 pairs. at the end there are "dry" areas on the topsheet and there are areas that got soaked through with epoxy and therefore are "wet". because they got wet on those areas the wood looks different, mostly darker.
on the alberich i did following: after pressing i coated the whole topsheet with epoxy so that even the dry areas got wet. i mixed the epoxy with methanol so that the epoxy got really really liquid and got soaked in easier by the wood. i let everything cure and then sanded off the remaining epoxy on the top of the wood until there only remained "epoxy soaked wood". this resulted in a pretty hard, though looking, shiny surface. then i sprayed on the pitchfork grafics with stencil print and aerosole spray colour and added an other layer of thin spray varnish.
this method involved a lot of sanding and needs quite some time...sanding, epoxy, sanding, varnish....eeew!
therefore i tried to find a faster way of doing topsheets. this is what i did on the mimir:
as the skis came out of the press the veneer showed those dry and wet areas too. i just sanded the veneer and coated it with marine coating (this stuff is called coelan and is said to be a little elastic). you might be able to see it on the picture i posted earlier: the ski on the left looks not that good... because i applied a pretty thick layer of this coating/varnish it was nearly impossible to get an even, nice and clean looking surface. the pair on the right looks better, but still i`m not that satisfied.
so in general:
the epoxy-spray varnish-method creates a smoother surface because there is nearly no coating on the top of the wood. the "coating" all got soaked in by the wood. because the wood is (hopefully) fully soaked with epoxy it gets heavier, but also stronger and tougher. all in all the result is a pretty hard topsheet.
the marine-coating-method is a little quicker. if you can spray on this coating you`ll get a smooth surface too. the downside: there is a relatively soft coating on top of soft wood (because the wood itself is not that tough and hard and even thou it gets soaked with coating this coating is never as strong as epoxy). this surface is more likely to get damaged by the steel edges than the epoxy-method. the edges just cut through the coating and hurt the wood so that there is dry wood exposed - BAD!
i didn`t ski the epoxy-method-ski much so they don`t show much abuse, therefore i can`t tell you for sure if the epoxe-method withstands abuse better. but i`ve got the feeling it does. at least there is no dry wood exposed when hitting the topsheet because the wood mostly got soaked by epoxy.
hope this helped a little...
the wood is european walnut, 0.9mm thick (there was no thinner veneer so i had to take this. maybe thinner veneer would reduce the problem because it might get fully soaked with epoxy during pressing and therefore you could save one step on the epoxy method).
rocker sections expressed as a radius.... ew! tip and tail rise for about 20cm to a height of 45mm. so i guess the radius is about 40cm or so? as those were built mainly for slope & park skiing i did a "narrow" tip radius as i didn`t want long tip and tails.
plywood freeride industries - go ply, ride wood!