How to Miter Corners in Wood Moldings

Miters are angled cuts designed to fit with other angled cuts to form corners.
When mitering a corner in wood molding, you'll be making both your miter cuts at 45 degrees. So when they join on the outside of a corner, they add up to a 90-degree angle - a corner, in other words. You can cut the miters with a circular or other saw, but stationary miter saws work best because the blade is affixed on a swiveling platform that turns to the correct angle.

Step 1

Measure the wall to determine the length of molding you need for the first side of the corner. Transfer the measurement to a piece of molding, marking on the top of it with your pencil.

Step 2

Set the piece of molding on your miter saw, in the position it will be on the wall. Swivel your miter saw blade to 45 degrees away from the main body of the piece. Make sure your molding is positioned so the blade is on the marked line at the back of the piece, but angles away from the line at the front.

Step 3

Make the cut by bringing the blade down in one steady motion while holding the piece steady with your free hand. When the miter cut is made, the face of the piece should be longer than the back.

Step 4

Measure the length of molding you need on the other wall and mark it on another piece of molding. This time, you'll reverse everything from how it was on the first cut, with your trim on the opposite side of the blade and the saw swiveled at 45 degrees in the opposite direction (but still pointing away from the main body of the piece). Make the cut.

Step 5

Set the two pieces in place, joining them at the corner to make sure they fit. Secure each piece to the wall with the trim nailer.

Things You Will Need

  • Tape measure
  • Pencil
  • Wood molding
  • Miter saw
  • Trim nailer

Tip

  • Follow the same steps for inside corners, except that your miter cuts should point inward, toward the body of the molding, instead of outward.

Warning

  • Wear eye protection when using a miter saw.