Baseboard trim
One of the most difficult things to get right when laying baseboard trim is join "inside corners" (the four corners of a room). For protruding "outside corners," you can usually just miter your trim at 45 degrees to make it fit. But inside corners are usually not square, which means a simple miter won't give you a tight fit. Here, the solution is a coping cut, where trim on one side of the corner is installed flush to the end of the wall, and the other side is cut in profile so it fits around it.
Instructions
1. Measure and cut the end of the your first piece of baseboard trim on your miter saw, set at 90 degrees, so it's a straight cut across the width. Install the piece onto the wall with the trim nailer so the straight-cut end of it is sitting tightly against the adjacent wall.
2. Set the of trim on the saw platform in the way it will go against the wall. Swivel the blade of the miter saw to 45 degrees inward (toward the body of the trim). Make the cut. It should leave an exposed area of cut wood along the end of the board, at an angle, with a line on the surface of the wood that mimics the shape of the trim.
3. Hold the trim in one hand. With the other hand, set the blade of your coping saw near the end of the board, where the exposed wood meets the finish of the surface. Position the saw so that it's perpendicular to the piece.
4. Run the saw back and forth, following the shape of the exposed wood (which will be determined by the shape of the trim). Keep the saw perpendicular to the trim. Continue until the chunk of exposed wood falls away, leaving you with the shape of the miter cut, but no visible wood behind it as you look at the trim from the front. The cut should form a "hook" at the top of the trim, based on its shape.
5. Set the coped piece into the corner, setting the "hooked'' cut around the surface of the previously installed piece. It should fit right over it. Install the second piece using your trim nailer.
Tags: , corners usually, inside corners, , second piece, shape trim