How to properly use the Mirror modifier ?!

[Tiago]

Hi all.
So, posting it here because I am having some hard time trying to figure it out by myself.

So, I am trying to model a sword, and I just created those “fangs” at the bottom, and I wanted to mirror it to the other side.
Is there a way to set the pivot to the center of the global axis?
I tried to mess with the parameters on the mirror options, and nothing.

Thanks in advance.

[Valence3D]

Cool sword. the easiest way to mirror it is to move the pivot to the center. Then go into face mode, select all the faces and move them left or right.

[teekstiptime]

VALENCE 3D - 005 - MIRROR MODIFIER

[Tiago]

Thanks you guys.
I was super confused, but now I managed.