>> If i do now a subtract solid on the 3D object shouldn't this also change my 2D Object?

Hi Martin

Generally a boolean (subtract, union,intersect) is an operation that works on solids. Something that has well defined inside and outside. I tend to think of booleans as operations that add or remove volumes of material.

It might also help to think of it in terms of parent and child relationships. These get created under the hood when you extrude a curve into a solid and allow you to modify the curve and have the part update. The 2D object is a parent that defines all downstream operations(child). In this situation, the dependancies are one way. You cannot modify a lower level child and have the upper level parent modify without causing a circular loop.

2D Object -> Solid -> Features (shell, blend,chamfer,cutout, hole, protrusion)

Hope this helps.

Tim

Edited by user Friday, October 3, 2014 9:46:26 AM(UTC)  | Reason: Not specified

>> Is this also valid, if the 2D Object is a cut section of a surface?

Hi Martin

If you use an Infinite Plane to create a cut through a curve, surface or solid the resulting section will update if you change the plane or curve/surface/solid. In this case the cut section is a child dependent on two parents (plane & body you are cutting). Moving either parent will update the child geometry.


Tim