How to I cut glass and marble tiles when they are on a mesh backing?
Ahhhhh no wet saw for small glass mosaics.  First it will bounce all over when cutting and second you might get a nice chunk of glass in you.

You will be cutting everything one mosaic tile at a time.  Take it off of the mesh.

#1 Make sure when laying out your tile that your cuts are in the corners or in less seen areas.  

#2 If you need to cut the corner of a tile or odd shapes use glass nippers.



The nippers are not a precision tool.  With a little practice you can get close to what you want.  Luckily doing mosaics breaking a couple of squares is relatively cheap.   If you have a weird corner cut on a tile or a circular cut and you can get it done in 2-3 tries the great job.

#3 For straight cuts you use a wheel scorer.  The picture I have below is a double sided.  Often you will just see a single wheel.  Just like cutting drywall it is most important to get a good score on the glass side.  With a little muscle you should only have to roll an area 2-3 times.


#4 Once you have a line on the top of your tile we are going to move it over to the tile cutter.  You are going to place this faced up with the edge right on the cut line.  This takes practice and is a little different with each cutter.  You will gently (do it to hard and cut may not be clean) bounce the lever to put pressure on the tile.  If it is lined up right eventually it will break clean on your scored line.  If your cut isn't clean then you may need to score a little deeper or line it up better on your cutter.  Also do one tile at a time.  I know it seems a PITA but you can do 2-3 tiles in a minute once you get it down.  Also do your cuts before you start applying thinset or have a helper.