# Why is X mirror not working on a mesh?

Does X-Axis Mirror work on a mesh? I applied X-Axis Mirror to a set of bones and it worked but not on the mesh, I tried to mirror the mesh using the X-Axis Mirror option but it doesn't mirror anything.

Here's the .Blend.

• Could you explain your question in a bit more detail?
– gandalf3
Jun 18, 2015 at 20:12
• I tried to mirror the mesh using the X-Axis Mirror option but it doesn't mirror anything. Jun 18, 2015 at 20:36

The mesh isn't exactly symmetrical.

This behavior is intentional. Meshes which are almost (but not quite) symmetrical wont detect vertices as mirrored.
This is needed to avoid problems with high-poly meshes where vertices may be very close.

To resolve the problem, you can use the Snap to Symmetry tool.
See: Mesh -> Snap to Symmetry.

This has options to select a distance threshold and choose which side of the axis to use.

This is because your mesh is not symmetrical.

X mirror looks for a corresponding vertex on the opposite side of the object's origin:

Grabbing the vertex at 1 will look for a vertex at 2.

If your mesh is not symmetrical, chances are there is no vertex at 2. If there's no corresponding vertex, then X mirror can't do anything.

• What if I deleted half of the mesh? Would it work? Jun 18, 2015 at 21:12
• @ChristopherMonday Yes, if you mirrored the remaining half back over to the other side, in order to provide X mirror with something to work off of.
– gandalf3
Jun 18, 2015 at 21:14
• @ gandalf3♦ It didn't work drive.google.com/file/d/0BwnCnOOEcD5qbGJGZXphQU9LR1E/… Jun 18, 2015 at 21:26
• @ChristopherMonday It's still asymmetrical. You need a symmetrical mesh with symmetrical topology for X mirror to work properly.
– gandalf3
Jun 18, 2015 at 21:28
• Looks symmetrical now...drive.google.com/file/d/0BwnCnOOEcD5qek1CVUxVWlZCeHc/… Jun 18, 2015 at 22:24