No matter if you’re working on new construction or remodeling, you will rarely find two walls that are at an absolute 90-degree angle. So getting two 45-degree miters to meet perfectly tight in a corner can be frustrating, especially if the molding you’re trying to miter has an intricate profile.
The secret for tight-fitting trim on inside corners is coping the joint. Carpenters have been using this foolproof technique for years. It involves cutting the profile on the end of one molding and fitting it against another, like pieces of a puzzle.
In a coped baseboard corner, one molding has a square cut on the end that butts up against the adjacent wall. The other molding fits perfectly against the face of the first molding by cutting the end to follow the profile of the first molding.
You only need a few tools for this job: a coping saw, a miter saw, and a round file. It’s always nice to have a few sharp coping saw blades on hand. Sandpaper is handy to fine-tune your work.
Set your miter saw at 45 degrees to the left. Now position the molding upright so the back is flat against
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