Of the several tools used to mitre ceramic tile, the tile wet saw most effectively creates a clean-edged cut and accurate angle. The tile wet saw is essentially a table saw designed for cutting masonry and tile materials. Two of the tool's components contribute to its effectiveness: a diamond-coated saw blade and a continuous distribution of water that cools both the blade and the tile. Mitre cuts are so common that tile wet saws include specialised equipment to guide the tile through the blade at precise angles. For single use or small projects, you can rent tile wet saws by the day or hour from home improvement stores and tool rental shops.
Place the tile wet saw on a flat surface, such as a workbench or a concrete slab. Attach a diamond blade to the tile wet saw. Fill the saw's water reservoir with fresh, clean water.
Lay a carpenter's square or framing square on the glazed surface of the tile. Position the square across the tile along the desired location of the mitre cut. While holding the square in position, use the edge of the square to draw a cut line across the tile's surface.
Attach the mitre guide to the saw's rip fence. Lay the tile in the mitre guide and unlock the rip fence. Slide the rip fence until the tile's cut line aligns with the saw's blade. Lock the rip fence in position and move the tile away from the blade. Put on safety goggles.
Plug in the saw and switch the machine to the "On" position. Grip the mitre guide at its extreme edges to keep your fingers away from the blade during the cut. Slowly push the mitre guide forward until the spinning blade contacts the tile. Firmly push the tile through the blade to complete the mitre cut.
Turn off the machine. Slide the mitre guide away from the blade. When the saw blade stops spinning, remove the tile from the saw's table.
Although it's tempting to purchase inexpensive diamond blades, low-quality blades tend to chip glaze from the edges of ceramic tile.
Never operate a tile wet saw without safety goggles; shards of tile occasionally fly during the cutting process.