How can I center a subtool on the 3D space when I’m on edit mode? Can I do it on the X axis only, so the X mirror symmetry lands right on the center of the subtool?
I usually take the object to max and center it there, but maybe there’s a way I don’t gotta go to max?
Select your subtool. Turn on the floor so you can see your axis guides. Use the deformation panel offset button. You can select whatever combination of xyz direction you need to bring the mesh to the center position.
Nancyan’s instructions will physically center the model (as would Tool>Deformation>Unify). This is, however, a permanent change. If your model has multiple SubTools you might find yourself in trouble going that route.
A non-permanent way to do this is to use Transform>S.Pivot. This temporarily centers the model’s origin on the center of it’s visible polygons. (If the whole model is visible, then it’ll be the geometric center of the model.) This affects rotation and symmetry. But when you later use C.Pivot ZBrush will clear this pivot point and return the model to its original origin.
What will happen if you have a model that has multiple SubTools is that pressing S.Pivot will cause the selected SubTool to jump to the entire model’s 0,0,0 point. Don’t worry about this – just hide the rest of the model so it doesn’t distract you. Use symmetry and so forth to your heart’s content. When done, press C.Pivot and your model will jump back to where it started so that it still fits right with the rest of your SubTools.