The spacepilot video is doing "surface modeling" and is a more advanced method. There will be many things to understand to do that correctly.. Start with "solids modeling" as a beginning point.

Great !!!! Thank you both of you.
It's perfect. I have not the taper method on the extrude function, probably because i use MoI V2.

It's right that i'm coming from poly modeling and this kind of method is not very good. But here, it is very nice and simple. I need to change my reflex :)

""""""""""I have not the taper method on the extrude function, probably because i use MoI V2.""""""""""""

Check out the tutorial by Danny at:

http://moi3d.com/resources#Tutorials

Named "Accurate tapers using Expressions by Danny"

for tapering your extrude.

Excellent, this forum is a real goldmine
Thank you

Cool example BurrMan..

Peace,
Rich_Art. ;-)