Ski Builders Forum

Hi pmq!

nice documentation and nice features. It is possible to see the passion you get from skibuilding which is i think the best about it.

the tips. I don t think it is because of vertical tension... Amount of vertical tension must be minimal in contrary with some stress for example while flexing skis. And overheating seems to me also as almost impossible. When finishing in mainstream factories, they do it quite hard...

what about "only carbon" lamination setup? That must be quite weak without some amount of fiberglass, isnt it?

Hi pavel,

overheating in this case is about 100-120°C, when the epoxy fails. This can be done easily when grinding an edge without water cooling. Well, it may also be that the laminate just was not good in this area, perhaps my tips are bent upwards too hard (if the edges are not pre-bent).

For this ski I will build a tip protection that keeps everything together, although I dislike the thought of additional weight on the tip. For the next skis, I will either build a new tip shape, or, what I think I will do, unharden the edges in the tip section. Then they keep all the bend they get in the mold, and there is no force pulling the laminate parts away from each other.


Regarding carbon:
Usually its said that carbon is 2-3 times as strong as glass fibre. So the 450g/m² carbon equals 900g/m²-1350g/m² glass. Well, this ski is pretty stiff, and torsionally rigid. Exactly how I wanted it :) We just don't have enough soft dry snow conditions to ride soft skis - and I will always want a ski that performs on piste as well. This one will surely do, as it has a minimal camber of about 5mm, and a "step-on rocker":

If the ski is unloaded, it hardly has any rocker. But if its pressed flat, the tip and tail sections rise a bit producing a rocker shape.

You definitely want to pre-bend the tip and tail sections. I struggled with the same issue early on. Pre-bending makes a huge difference and you shouldn't need anything extra to hold the tips together.

Also I usually wait 4-5 days after the ski is out of the press before I finish a ski so the epoxy has time to fully cure. Too much handling and flexing right out of the press can cause delams as well.

My tips rise slowlier up under bigger radius which is connected with a wealthier rocker and there is almost no tension...

about the carbon.... I know it must be stiff enaugh but I should maybe use term "fragile" without glass... friend of mine from lamination industry adviced me not to use "pure carbon"construction and not to put carbon directly on bases because it iwould be very fragile...

I know european conditions very well. I also appreciate stiff ski, but I ski offpiste even if there is no powder. So I am improving my skiing skills on shits like hard crud act... :D But having rocker alows me to go faster in any kind of snow....It is true that the ski must be then the stiffer if you have the rocker...

Seems to me there are allot of large companies making pure carbon construction. Its not fragile by any sense of the word.

pavelbozak wrote: I know european conditions very well. I also appreciate stiff ski, but I ski offpiste even if there is no powder. So I am improving my skiing skills on shits like hard crud act... :D But having rocker alows me to go faster in any kind of snow....It is true that the ski must be then the stiffer if you have the rocker...

Same here, also going offpiste a lot, even if the conditions suck. Also am a mogul fan - though I killed 2 pairs of skis in there last season :)

So, regarding the delam on the tips, I will build a new tip shape for the next skis. A more rockerlike one with less rise.
I am not sure about the vertical pre-bend of the egdes, its just a damn lot of work, as the egdes get un-bent a bit (horizontally) when bending them vertically. I think I will try unhardening them.


Regarding carbon again:
I actually wanted it this way, as carbon is a good way of building light skis, and also because I use ash as wood - ash is quite damp, and carbon has some more spring-like character than fiberglass. And the combination of ash and carbon seems nice (the feeling when pressing and releasing the ski, haven't skied this combination yet).

The step-on rocker

As some may think that this ski has a very traditional camber, lets have a look at the rocker construction. I call it step-on rocker, as the ski has no real rocker when completely unloaded.




In this picture you can see the whole camber/rocker line. Notice the flat parts in the tip/tail section (Actually they are not completely flat, but a continous very soft up-curve). As soon as some load is applied, they rocker up a bit.

The unloaded skis tip section:




And when the skis are pressed flat together:




In the last 2 pictures you can also see 5 holes drilled through the tips. I will do some rivets through there tomorrow to keep the tips from delaminating further. I started building a real nice stainless steel tip protection today, but after 2 hours of work I decided that it was just too much work. Going for the easy version now, will look quite nice with the printed fabric I think.

I've wanted to put done punk pyramid studs with s screw on back on some skis for a while. A 1/4 pyramids screw back epoxied to the ski would look cool.

Like the old yellow Seth pistols with the Josh Malay graphics of the punk kid? They had pyramid studs if I remember right.
Great documentation and detail. I feel very agricultural seeing some of these threads.

Bindings mounted, base grinded, edges sharpened, ready for the first test on saturday :)





And yes, I am crazy :) Had to dry test them:




Cheers
Philipp

Geilomat!

I am building my first ski right now. Last night I started bednig the edges. Now my thumb hurts like hell since I dont have an edgebender and I didn´t want to heat them up.
Thanks for the idea with the modified pliers!

And yes, I am crazy :) Had to dry test them:

Nice, I always have to dry test my new pairs too..... not crazy alone.....:D

I have seen the weather forecast for austria... so much snowfall, My legs are impatient but I should wait for the second or third snowfall. Cause of my impatient there are always big holes from rocks in my bases... :D

You think you're crazy for trying the skis on at home? I'm pretty sure I've strapped in to every pair of new skis at home and done nose presses in the living room. Best way to test the flex in my opinion

Success :)

Was on the glacier 2 days ago and tested the ski. As it is the 6th ski I built (and the 3rd I tried riding) I do not have the experience yet to say in advance "Yes, this ski will rock". Have to test it on snow.

And that test worked pretty well! The ski performs well on piste, and of course offpiste anyway. I have never ridden a ski this wide (its still slim for most of you I know), and its really effortless compared to my normal skis.

With a length of 185cm and a radius off 22.222 meters its definitely not a ski for short turns, middle and long turns at middle to high speed is what the ski likes - and I do, too :)

Nice work pmg