Ski Builders Forum

Is there an easy program to simulate bending of profiles (core profile)? Would like to experiment a little bit with different profiles /trapez/concave/convex) without cutting up too much material (other problem is my limited access to the profiler i use).
I know theres stuff like mathlab and so on ... but im searching for a easy solution with not too much rocket science

http://www.mediafire.com/?w2zhdmuzkam

This is an older xls spread sheet that allows you to input some data to help with core design and will give an approximation of stiffness.

http://www.skibuilders.com/phpBB2/viewt ... calculator

I haven't used this yet but others seem to think it works

Thanks, i have this spreadsheet already. Youre limited (without hacking) to these params, so just trapezoid cores

Tip Thickness 3 mm
Mount Thickness 9,5 mm
Tail Thickness 3 mm
Tip Start 710 mm
Mount Start 200 mm
Mount End 200 mm
Tail Start 710 mm


Im looking into solidworks right now, but this would be a steep learning curve

Anyways, maybe some wired thinking only while lying sick in bed with half finished ski in the workshop ... LOL

Solidworks is overkill for this kind of thing, you're talking FEM at that point.

I had a spreadsheet a long time ago that you could put in any arbitrary profile, and different kinds of loads (point loads, or different spread out loads) and it would calculate and display the deformed shape. I used that when I was experimenting with foam core on a pair a couple of years ago. It even took in the width dimensions of the core (sidecut).

I have no idea if I still have the spreadsheet somewhere, I probably don't. If you have excel, it's not too difficult. Just basic beam bending equations.

I made a simulator

http://www.junksupply.com/ski-calculator/

but I dont think it covers all that you had in mind.

Licens key is on the main page.

Cool, did see this before but forgot completely about it. As long as i can put enough vectors for the core profile (lets say every 5 to 10 cm) im totally fine.

Will try it out

@twizz: yes i know that solidworks is total overkill ... did look into beam equations but got stuck ... not enough basic theory inside my head

For a simplification, here you go (check out "center loaded beam"):

http://en.wikipedia.org/wiki/Deflection ... neering%29



where

F = Force acting on the center of the beam
L = Length of the beam between the supports
E = Modulus of elasticity
I = Area moment of inertia
x = Point along beam

@mikic: Tred it out, somehow i always get an error when i try to put in my 30 measure points

@twizz: Thanks a lot! I understand now (in theory) how to calculate the deflection of a beam ... to generate a diagram out of it should be easy.
But where i drop out ... how to project this formular on a non uniform beam with changing modulus of elasticy?

I have a vague idea (even hard to explain, learned this stuff sooo long ago i hardly remember)

Try to do this with just two sections:

xa .. xb .. E1
xb .. xc .. E2


So if i want to calculate the deflection for point xa to xc:

My 3 point would be like that:

xa based on E1
xb based on E1
xc: difference of E2 based xb and xc added to xb based on E1

LOL i know that this description would make my teachers turnover in their graves .... but after more then 2 decades not using this stuff i have to admit ... all is gone (at least for the moment)