you model an object, you should take advantage of any symmetry that
the form provides. It can save you time and effort if you work on
only one half of the model and then later copy it across the model’s
axis of symmetry. The sketch of the helmet is symmetrical along
its center line (YZ plane).
To delete the faces on the left half
of the mesh
the top view, right-click on the mesh and select Face from
the marking menu that appears.
- Drag a bounding box around the faces
on the left half of the helmet mesh to select them.
- Press the delete key.
The selected faces are
You now have half as
many components in your model. When you near the completion point
of the model, you will copy the finished half across the axis of
symmetry to get the complete model.