MAYA: Mirror image creates line at the center of my object

Question

I'm trying to learn modeling in Maya at Digital-tutors and I'm stuck at one point. I'm modeling an aircraft and made half of it and then mirror imaged.

In the tutorial there is no problem, but with mine there is a line at the center of the plane and when I do some changes like extrude, that line is opening.

Answer 1

You have to connect the vertices between the two sides in order for them to behave as one object.

First make sure your two sides are one object. Then you need to use the Merge Vertex tool to connect the vertices.

1. Select both halfs
2. Go to Mesh > Combine
3. Next you delete the history of the shapes so that Maya sees them as one image. Edit > Delete by Type > History
4. Then proceed to merge your vertices using the Merge Vertex tool.