I have this mesh and I did a grid filling. I converted quads to tris but why do I have quad faces left, upper left face for example?

• Which method of converting did you use? For example, if using Triangulate Faces with Ctrl + T while in Edit mode, the result will look much clearer - i.imgur.com/jlihyeW.jpg May 6 '15 at 15:33
• I used Triangulate Faces with Ctrl + T while in Edit mode. The problem is the grid filling method (bar space -> grid fill while in Edit mode), because I have this [grid fill] (imageshack.com/i/hlvHZoh6p) when I apply grid filling method on the mesh of the first image before converting quads to tris. And it seems you used a grid mesh ? Not a mesh like the first image, without faces. May 6 '15 at 18:02