Lets say i have a pair of scissors, in the middle is a screw which makes it possible for the blades to rotate around it. How do you implement this in a model? Basically I want to select a part of the model and then i want it to be able to rotate only around one axis.
Do I do this in the mesh itself or with bones?
Some help would be appreciated, thanks in advance.
In Blender there are objects of multiple types (object mode) and a mesh type object (object mode) consist of one or multiple mesh parts (edit mode). Pivot point in Blender is not a fixed point in 3D space but can change, depending on the mode and selection. In object mode, object’s transformation center is where its origin is when the default median pivot is used.
You could do both. Select vertices around the hole in edit mode and snap 3D cursor to it (shift+S). Then set the object’s origin to that in object mode (tool shelf -> origin, or ctrl+alt+shift+C). Now the object rotates around its origin when the default median pivot is used (ctrl+comma).
It’s a rigid object so you could parent the object to a bone, or could also use vertex weights (weight = 1.0). Don’t necessarily have to set the origin when using an armature but there’s no harm done if you do.