Cutting Mitered Joints for Trim Molding
- 1). Determine the length of trim molding needed for the first board. Stand the board on end as you would when placing it against the wall and measure across the top to make a pencil mark on the trim molding board approximately a half-inch into the board length. This mark will signify the cut-point for the first miter.
- 2). Set the miter saw to cut a 45-degree angle in the direction needed for the first cut. Stand the board up against the saw in the same way it will be positioned against the wall and place the blade over the mark. Lift the blade arm to a few inches above the wood trim and press the trigger to activate the blade while holding the trim flush against the back of the miter saw frame. Pull the blade arm down to cut evenly through the wood and then lift the arm again before releasing the trigger.
- 3). Measure the length for the next board--the one that will join with the previously cut piece. This board will cut on the opposite side from the first board. Place the cut mark at the back top and a half-inch into the board.
- 4). Set the miter saw to cut another 45-degree angle, but this time the opposite direction from the first cut. Position the board against the miter frame with one hand, and lower the blade to the mark to test for proper alignment. Adjust the board as necessary. Lift the blade arm, press the trigger to engage the blade and smoothly lower it onto the trim board until it cuts fully through. Lift the blade arm and release the trigger.
- 5). Position the two boards against the wall and align the board junctions to form the 90-degree angle needed. After anchoring the boards with 1-inch finishing nails to the wall into the stud frame, fill any gap in the miter joint with paintable caulk to give a good tight fit.
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