Cutting perfect corners is a critical skill for any tile installation, whether you’re a professional or a DIY enthusiast. A flawless corner cut not only provides a clean, professional finish but also ensures the longevity of your tile work by preventing chips and cracks. This guide will walk you through the precise process of making miter cuts for outside corners, the most common and aesthetically pleasing method for tile corners.
Part 1: Safety and Tool Selection
Before you begin, gather the necessary tools and prioritize safety.
1. Essential Safety Gear
- Safety Glasses: A must-have to protect your eyes from flying tile shards and dust.
- Dust Mask or Respirator: To prevent inhaling fine tile particles, especially when using a wet saw.
- Gloves: To protect your hands from sharp tile edges.
- Hearing Protection: If using a wet saw or angle grinder, ear protection is essential.
2. Choosing the Right Tools
The tool you use depends on the type of tile, but a wet saw is the preferred tool for a clean miter cut.
- Wet Saw with a Miter Function: This is the ideal tool. It has a diamond blade that cuts tiles precisely while a water tray cools the blade and controls dust. Most wet saws have an adjustable fence that allows you to set the blade at a perfect 45-degree angle.
- Angle Grinder with a Diamond Blade: This is a good alternative for small jobs or when a wet saw isn’t available. It’s more difficult to get a perfectly straight and consistent miter cut, but it’s effective for shaping and smoothing.
- Finishing Tools: You will also need sanding blocks or a rubbing stone to smooth the cut edges and a level or square to check for accuracy.
Part 2: The Step-by-Step Cutting Process
Follow these steps for a clean and accurate miter cut.
Step 1: Measurement and Marking
- Measure Carefully: Measure the distance from the edge of the last full tile to the outside corner. Remember to subtract the width of the grout joint.
- Mark the Tile: Use a pencil or marker to draw a straight line on the face of the tile. This is your cut line. For an outside corner, the miter cut will be made on the long side of the tile, as the grout line will be on the short side.
Step 2: Setting up the Wet Saw
- Adjust the Blade Angle: The most crucial step is to set the saw’s blade to a 45-degree angle. Most saws have a lever or knob to lock the blade into this position. Double-check the angle with a protractor or a small square to ensure it’s accurate.
- Check the Water Tray: Make sure the water tray is filled to the correct level. This keeps the blade cool and prevents dust from becoming a hazard.
- Test the Fence: Align the fence to the blade to ensure the tile will pass through evenly and squarely.
Step 3: Making the Cut
- Position the Tile: Place the tile on the saw’s bed, with the face of the tile facing up. Align your marked line with the cutting path of the blade. The side of the tile that will be visible on the finished wall should be facing outward.
- Start the Saw: Turn on the saw and allow the blade to reach its full speed before beginning the cut.
- Cut Slowly and Steadily: Push the tile gently and consistently through the blade. Don’t force the cut. The blade’s diamond teeth are designed to grind the tile, not chop it. Forcing it can lead to a chipped or crooked cut.
Step 4: Finishing and Refining the Cut
- Clean the Tile: After cutting, clean the tile to remove any slurry or dust.
- Inspect the Cut Edge: Carefully inspect the cut for any small chips or rough spots.
- Smooth with a Rubbing Stone: Use a rubbing stone or a diamond hand pad to gently smooth the cut edge. A few light passes are all you need to create a clean, crisp line that will look professional. The goal is to remove any sharp points, not to change the angle of the cut.
Part 3: Installation and Final Tips
1. Dry-Fit Before Installation
- Before applying mortar, always dry-fit the two mitered tiles together to ensure they form a perfect 90-degree corner. If they don’t, you may need to make a small adjustment to your cut or use a rubbing stone to fine-tune the angle.
2. Applying Mortar and Setting the Tile
- Apply mortar evenly to the back of the tile using a notched trowel.
- Press the tile firmly into place, ensuring the mitered edge is flush with the wall.
- Repeat the process for the second tile, carefully aligning the two mitered edges to form the corner.
3. Grouting the Corner
- After the mortar has set, apply grout to the joint. Use a grout float to press the grout firmly into the joint, then wipe away the excess with a damp sponge.
