Use the Knife Subdivide Tool to create new edges on curved surfaces.
- Activate the Knife Subdivide Tool
- Click the first point on a surface to start a new edge
- Continue clicking points on the surface to create edges
- Press ESC stop cutting and reset the tool.
- ALT = Hold while clicking to also cut through back-faces. By default, only faces that are pointing towards the camera will be cut.
- The Knife tool supports inferencing. You can tap arrow keys to lock the cut along the red, blue, or green axis.
- The Knife tool will often create N-gons which will not subdivide well. If you intend to use the Subdivide and Smooth feature after using the Knife Tool, it is recommended to convert your geometry to quads as much as possible after making your knife cuts.