Still doing the following tutorial: http://www.blendercookie.com/2009/01/09/modeling-a-human-head-series-part-1/
I am at this point, where the plane mesh should be mirror modified: http://juskalampela.com/blender_mirror.jpg
Since the tutorial is a bit dated, I can’t see which particular mirror modifier settings are being used. Could someone list the proper settings, just to make sure that I proceed correctly?
You basically disabled all the settings in the modifier.
First check ‘X’, to mirror on the x-axis.
Merge & Clipping could be helpful too. ‘Merge’ to merge vertices that aren’t exactly in the center (the default Merge Limit is 0.001). ‘Clipping’ to keep the vertices located in the center, in the center.
Btw, the object’s origin point (the orange dot) is used as the point to mirror from. In your example it doesn’t seem exactly located where you want.
Set your 3dcursor to the center (shift+C), then in object mode press Shift+Ctrl+Alt+C to set the origin to the 3dcursor
Thanks, back to work then. 
One more issue: when I mirror the X-axis, for some reason it mirrors the object in Z-axis (vertically). Any ideas what might be causing this? Maybe it has got something to do with orthographic view…?
1 explanation is that you rotated the object in object mode. To check this, either Clear Rotation (Alt+R), the object will go to its original rotation. Or Apply Rotation (Ctrl+A-> Rotation), the current rotation will become the default rotation
Your explanation was correct, hopefully no more issues with mirroring.
