By Sonia King

© 2004
excerpted in part from Mosaic Techniques & Traditions
published by Sterling Publishing, 2003

Envisioning a mosaic design and bringing it to life becomes easier when the basic skills of shaping and assembling the tesserae are understood. Many of the techniques covered here are essential for beginning mosaicists while others may help experienced mosaicists reach a more advanced level.

Creating a mosaic is like solving a puzzle. Mastering various techniques allows the mosaic artist to not only "solve" the puzzle but to control the shape of the pieces. But it is important to understand that there is usually more than one way to do something. If you've found a good method that works, then use it!

Shaping the Tesserae

One of the first questions beginners always ask is "How do I cut tiles?" While the process is commonly referred to as "tile cutting," it really is "tile nipping." A mosaicist doesn't actually cut tiles but rather controls a fracture. A tile wants to break in the easiest way possible, but the easiest way usually doesn't result in the desired shape. The more cutting techniques you master, the greater "vocabulary" you have to work with. This will make things both easier and harder, because the bigger your vocabulary, the more complex your thoughts!

Understanding how the tools work and how the various sorts of materials break make it possible to shape the tesserae with minimum effort. First, look at the jaws of a basic side-biter nipper such as the Basic or Precision Nippers when it is closed.

Note that the jaws don't meet fully but rather leave a gap. If the jaws closed completely, you would be crushing the tile rather than nipping it. For the same reason, only a small part of the tile is covered by the side-biter when nipping. If the jaws cover too much of the tile surface, nipping would become crushing and it would require a great deal of brute strength. By applying pressure on a small amount of the tile at its edge, you create a fracture across the surface. This technique allows you to cut a lot of tesserae without tiring. The trick is to learn to direct the fracture in order to control the resulting shape.

Now look at the nippers from a side view. Note that the jaws stick out on one side while the other is flat. The side with the overhang is the primary cutting surface. Cutting with this side is called "nipping." Certain cuts require using the center part of the jaws. This is called "nibbling." Occasionally, the flat or backside is used. The term for this is "backbiting." A small percentage of mosaicists cut primarily with the backside. If this works best for you then, by all means, you should use this technique.

Hold the nippers at a side view and look at the flat profile of the top of the jaws. How the top edge lines up with the tile determines the angle of the cut. If the top edge is parallel with the tile edge, the cut should be straight across. If angled, the cut should follow that angle.

Here are the basic steps for nipping tile with side-biters. Sitting in a proper position and knowing how to apply pressure for nipping will make the process both safer and less tiring.

Step 1: Put on safety glasses.

Step 2: Sit with your forearm relaxed on your thigh and lean slightly forward. Keep your arm fairly straight so that your full strength can go into the cut. (A bent elbow binds up some of your strength and will require more hand pressure.)

Step 3: Hold the nippers at the end of the handles to allow for maximum leverage and easier cutting. Position them so that the pressure is exerted from the meaty base of the thumb rather than the soft "vee" between the thumb and forefinger.

Step 4: Hold the tile in the opposite hand. Position about 1/8 inch (.3 cm) of the jaws on the edge of the tile.

Step 5: For a cut straight across the tile, align the top edge of the nippers parallel with the top edge of the tile.

Step 6: Position your thumb and forefinger of the opposite hand across from the nippers.

Step 7: At the same time that you smoothly squeeze the handles of the nippers, squeeze the opposing thumb and forefinger. Pinching the edge of the tile as the nippers pinch the other edge will direct the fracture straight across the tile.

All this requires practice but it will soon become second nature. Nipping, nibbling, and backbiting allow you to cut any needed shape. Different kinds of tile, different colors of the same tile, and even different color batches may cut differently. With experience, the necessary adjustments in pressure and position become automatic.

Vitreous glass tile can be cut using the basic shaping techniques described above but here are a few additional instructions. Note that the back of the tile has a ridged surface and a beveled edge. Making the first cut perpendicular to the ridges usually results in a better edge. Cutting parallel to the ridges often causes the tile to break unevenly. If you are cutting the tiles into quarters, then side-biters work best. They are also essential for trimming edges or working on the beveled edge. If you are cutting a lot of vitreous glass or other shapes, Wheeled Mosaic Nippers are a valuable second tool. Note that the wheels are positioned over the center of the tile rather than on the edge.

Hold the tile by the edges with your opposite hand and squeeze the nippers. The tile cuts easily. The Wheeled Nippers are especially helpful for cutting out triangles and long slender shapes. Another tool is the Chipper Nipper. This one is great for creating circles. Just hold the chipper with the angle pointing away from the tile and work your way around the desired shape.

Understanding your tools and the properties of the tile you're cutting will make your life much easier. And remember it will take practice for the techniques to become second-nature.