Machanics: Where to section?

[kasse]

I'm about to draw shear and moment diagram in 2D, and I wonder if there are any general rules as where to section for instance this ski?

http://www.badongo.com/pic/504635

 

[radou]

What do you mean by "as where to section"?

 

[kasse]

Where to make the sections.

 

[Pyrrhus]

I guess it depends on you want, but in this case there will be 4 moment equations (sections).