# How to make grooves without editing geometry

I'm trying to cut grooves onto a curved surface without directly editing the geometry. This is my desired end result that I achieved by Ctrl+B to bevel and E to extrude down (Exactly what I don't want to do).
Is there a way I can do this with modifiers or something like that? I will occasionally need to edit the fine details of the mesh and I can't do it whilst these grooves are physically preset, and I need them there for reference. I also can't bake a normal map for it because the materials are geometry defined and my change too. Thanks in advance.

You can add a groove using a boolean modifier.

My process would be as follows:

Duplicate some faces from your original, then separate them into another object.

Scale them down, and extrude out some thickness to get the inverse of the groove you want:

Add a boolean modifier on the first object set to difference, and select the new object as the target:

Then, just hide the second object to see the groove:

You could make your extrusion mechanically, as you have, but to 0 height, make a vertex group from the extruded vertices, and aim a Displace modifier at it, followed by a Weld to disappear it when you set the displacement to 0.

• Advantages over the Boolean given by @person ? Not many.. unless the Boolean is playing up because of necessarily coincident faces
• Disadvantages .. you can only edit the unmodified mesh, which contains doubled vertices.

So probably, the Boolean is better.