Hi Yann,
Todd and I have done a lot of pre-production work with a few different manufacturers of skimboards here in the US. We have a pretty good idea of what works and what does not. Since you are about my size I think these overall dimensions will work nicely for you to construct something. Sorry if you need to make centimeter conversions... We are still a bit slow here on the metric system..
Yann wrote:I've outlined a pintail skimboard that I like the look of from the web, but need help with the noserocker and the rails. I've never seen a proper wave skim up close so I have no idea.
1. How high is the nose rocker if you put it flat on the floor?
2. How far back does it start?
3. What about tailrocker? Is there any or completely flat?
4. What shape are the rails? Square, 50-50, pinched? Are they the same shape all over or are they sharper in the back?
Any help is appreciated.
Yann
Overall dimensions should be somewhere around 54" x 20.5".
The shape I would recommend in a more wave oriented board would have about 2" 1/4" - 2- 1/2" of nose rocker. It should start at about 18" from the nose. There are several boards out there that have less nose rocker, but they do not work as well in wave conditions, and are more suited towards riding flat water. For instance my favorite flat water board has 1 - 3/4" of nose rocker, and there are some that have less. This board has a stickier feel and pearls easier on bigger than chest high waves.
Again there are some skimboards out there with no tail rocker, I prefer that the board I ride should have some tail rocker for release. I would recommend up to 3/4" of tail rocker depending on how loose you want to make the board. The more tail rocker you add does slow the board down and make it feel a lot looser when you ride it in a straight line.
As far as rails go I would build up the rails and start with them square. Many of the boards I have had have extra material on the rails and are built sharp so you can sand them to your tastes. I just finished testing a board that had very sharp square rails and the board was super fast, but hard to ride and overall it was too specialized for the average person to enjoy. The rails should have and edge to them but not be sharp enough to feel "sharp" or cut you - if you can understand what I mean. However, I do not think they should be tucked like a surfboard.
Let me know what other questions you have or what I can explain further.