This can be very frustrating for some people. You need a precise cut on your glass tile and you just can’t seem to get what you want. There are ways to cut glass tile to almost perfection. However, you must remember that glass is glass and it tends to have a mind of its own sometimes. If you get a piece that will not cut well, then put it aside and try a new one. Glass has fracture points and it will break along its own line occasionally. You have to learn how to direct the cut.
Make sure to always wear safety glasses when using an mosaic cutting tool. You don’t want to get glass in your eyes.
Use wheeled cutters to cut most mosaic tiles. Some people use the basic nippers some have too many problems with them. To cut all the way across the glass tile in a straight line you need to cut quickly and efficiently. If you take too long to squeeze the cutters for a cut then you will end up crushing the tile. This crushed area will result in a poor cut that is curved. You can’t give the glass time to find its fracture point. Place your wheels where you want the cut and pop the tile apart with speed. Don’t let your cutters wobble either.
You still may have a ragged edge. This is normal and usually a desired effect. Most artists don’t want a “perfect” edge. They want it to all look hand cut. To clean up a ragged edge, slowly start nipping the rough area off. You can also use grozier pliers to pull off the unwanted part.
Practice really does make perfect on this. The more cuts you make on glass tile the better you will get. Remember that it will take a lot to dull your wheels. If they seem to be getting dull just rotate them slightly
You can use the wheeled cutters or basic nippers to cut the small ceramic or porcelain tiles. These will dull your wheels a little quicker but not enough to really matter. You will use the same technique as described above.
Basic nippers are used to direct the cut. Place the tile between the teeth. However, do not place the tile on the full surface. Instead, you will just hold it in the front or back of the nipper’s teeth. Angle the nipper to go with the direction you want the cut and squeeze. It takes a lot of practice with these but you can get some great keystone cuts this way.
A wet saw is used to take the large 12″ floor tiles and cut them into workable pieces. Use this for cutting ceramic, porcelain, and marble. You can start cutting down the large squares with a wet saw. After you get it cut into rods, use your basic nippers or a hammer and hardie to chisel it into small cubes.
A note of caution…make sure to wear protective eyewear and old clothes. You will get messy!
Hammer and Hardie
The hammer and hardie method is an old technique that a lot of mosaic artists still use. It consists of a mallet and a chisel tool. Place this tool where you want the cut and hit with a hammer. This is used for cutting marble, natural stone, and smalti. You can use it for cutting most mosaic tesserae though.
Of course, a hammer itself is a great breaking tool. You can use it to bust up large pieces of ceramic into a workable size. Make sure to lay a towel on top first. You don’t want to bust off your glaze.
A glass scorer is a tool mainly used in stained glass work. Mosaic artists will use it to cut down stained glass sheets. You can get a nice designed cut with this tool also. It consists of a tiny wheel that must be kept oiled. Just roll it on the glass and pop it apart with running pliers. It will take a lot of practice if you want to do cuts other than straight ones.
Your tile cutters/breakers will make the difference between a great mosaic piece and an “okay” mosaic piece. Find what suits your style best and stick with it. Whenever you can’t get a tile to cut just right, maybe you need to try a different tool.