I can't say I'd even know how to cut regular glass, but I've got some mirror glass to cut to about 11x20". Its from a $11 cheesy wood framed ~16x24" new mirror. I measured it at .081" = ~2mm thickness. So there are inches on the sides to cut off. I've bearing-rabetted out 3/8" around the inside of a 1x2" frame I made. Theres about .2" left to the front face I'll paint. I'm gonna back it with 1/4" Birch plywood, and brad it in w/ 1/4" 1/4 round (.500"Diameter).
1) should I worry about the birch ply right up against the mirror paint? Its not pictures.
2) Should I score the back side where the mirror paint is. Or grind it, or get through to the glass somehow, whether straight or not. Theres ~3/8" to the max edge on each side, so I could make a mess of the finish, I think, without affecting the view from the outside.
3)I am assuming no matter what I am going to do I need to score on the glass side
4) When scoring it says to score with one line only. How hard do I need to push? I just bought a $5 "6 wheels" Richard cutter. Then push down (away) from the cut line on the corner of a table?