A target object’s weight specifies how much the scaling of the constrained object can be influenced by a target object. The weights are attributes of the scale constraint. For each target object, an attribute named targetObject Wn is included that specifies the weight of each target object. By default, the weights are set to 1, which gives each target object an equal influence over the constrained object’s scaling. However, you can change the weights so that some target objects can have more (or less) influence than others. You can change target object weights with the Channel Box or Attribute Editor.
To change target object weights for scale constraints with the Channel Box or to change target object weights for scale constraints with the Attribute Editor, edit the targetObject Wn channels/attributes as described in Edit scale constraints.
You can animate the target object weights specified by the targetObject Wn channels. You can vary the weights from 0 to any value, so that as an animation progresses, different target objects can take turns driving a constrained object’s scale.
After you’ve created a scale constraint, you can remove any of the target objects so that the objects no longer constrain the constrained object. Removing target objects is similar to adding target objects.
To remove target objects
Note that when you remove a target object, you also remove any animation curves attached to the constraint object for that target object.
You can also remove specific axes from a constraint. For this procedure, see Remove a target object.