How to Cut Angles on Corner Molding Trim
- 1). Measure from one corner of the wall out along the horizontal span where the trim will go. Transfer the measurement to a piece of molding trim. Leave at least a few inches of space on both ends of the measurement.
- 2). Put the molding on your miter saw in the position it will be on the wall. Move it so the mark for the corner is under the blade.
- 3). Position the blade at 45 degrees, pointing inward toward the measured span for an inside corner and pointing outward away from the span for an outside corner. Make the cut.
- 4). Cut the other end of the board using the same process, swiveling the blade inward or outward depending on whether it's an inside corner or an outside corner.
- 5). Measure and cut the piece of molding for the other side of the corner in the same way, swiveling the blade depending on the type of corner.
- 6). Set the two pieces of molding in place on the wall, making sure the miter cuts form a tight seam. If they don't, trim them at slight angles on the miter saw until they do. Fasten the molding with a trim nailer, shooting two nails at the top and bottom of the trim every foot or so down the length of the trim.
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