AVOIDING A BROKEN KERF A common problem when cutting tiles is a broken kerf, which occurs when the tile breaks apart before the blade finishes a cut. This leaves a bump on one or both sides of the cut at the end of the kerf (7). This lip may not be a problem on a floor installation, but on wall installations where spacers are typically used, it can cause misalignment of the tiles. To maintain a completely smooth kerf, slow down the rate of feed as the blade exits the cut, and hold both sides of the tile firmly against the cutting table (8).
MODIFYING THE SAW FOR CUTTING GLASS TILE Special wet-saw blades are available for cutting glass, but chatter from the saw table can still break the tiles. So can excessive heat where the blade meets the glass. Also, the wide kerf slots on the table don’t offer adequate support, which can result in chipped edges along the cut. To minimize these problems, I bolt a square piece of 1/2-inch plywood — large enough to fully support the glass tiles — to the table. Then I submerge a second coolant pump in the catch basin. I wrap this added hose with stainless-steel wire, which stiffens it, but is flexible enough for me to direct the flow of water precisely onto the edge of the blade (9). Finally, with the coolant water flowing, I make a shallow cut in the plywood. The resulting narrow kerf provides maximum support for the tile, with significantly less chipping and fewer broken tiles.
FREEHAND CUTTING WITH A WET SAW Though not recommended by saw manufacturers (to limit their liability), freehand cutting can extend the flexibility and usefulness of a wet saw. Doing it safely depends on the installer’s steady hands resting firmly on the cutting table (10). Use both the edges and the sides of the blade for this type of cutting, and move the tile slightly side-to-side as you push it slowly into the blade. This movement widens the kerf and helps prevent the blade from pinching the tile and ripping it out of your hands, or — even worse — fracturing the rim of the blade and sending shrapnel flying into your face. Always use extreme caution, and always wear a full-face shield for any type of tile cutting.
IRREGULAR CURVED CUTS I make any irregular tile cuts freehand. The first step is to make a series of straight cuts toward the mark (11, 12). Next, I make additional shorter cuts, gradually getting closer to the mark (13). Finally, when the cuts are about 1/8 inch away from the mark, I use the side of the blade to finish the cut (14). With all freehand cuts, I keep the plane of the tile aimed at the arbor so that the shoulder of the cut is square to the surface of the tile. If held lower, the cut edge tapers out, and the tile probably won’t fit where it’s supposed to go (15). Keep in mind that the wet saw in these freehand cutting photos is over 65 years old and cannot straight cut tiles larger than 6 inches. Although it is not suitable for working with today’s larger-size tiles, I still use it a lot for intricate freehand cutting. You can cut just about any shape you want with a wet saw simply by following the steps outlined above. I should point out that freehand cutting causes irregular blade wear, and once a blade is used for this technique, it should not be used to make straight cuts. Generally, I use a blade for straight cutting until roughly a third of its cutting rim remains. I then use the remainder of the blade for freehand work. When the blade is no longer effective for freehand cutting, I still don’t toss it; I extend its life by using what’s left of the diamond rim to sharpen carbide-tipped drill bits.
COPED TILE CORNERS When joining cove or trim tiles for an inside corner, most installers simply miter the adjoining tiles. But just as with wood joints, a coped corner can be neater and more attractive. To create a coped corner, I make the profile cut using the freehand technique (16, 17).
RING SAWS There are several ring saws on the market that offer an alternative to freehand cutting. The same diamonds found on regular wet-saw blades are bonded to a hardened circular steel band or rod that cuts in the same way as a carpenter’s band saw (18). Like the blades on other types of diamond saws, the ring saw’s blade must be bathed in water, but rather than being sprayed with spouts or nozzles, it passes through a bath of water located below the cutting table. Some ring saws can cut porcelain tile and granite, but in my opinion, they are not well-suited for production cutting of these materials. I use a ring saw when I need to make a large number of irregular cuts in relatively soft materials, but for most irregular cutting, I prefer to use a conventional wet saw.