Lend a finished look to your moulding and trim with a mitered return cut
A molding will sometimes end in the middle of a wall instead of running into another piece of molding. The apron below a windowsill is the most common example, but in the course of putting up molding you'll run into others.
When a molding ends, trim carpenters don't just cut the piece to length, nail it up and move on. The most common solution is just to cut a miter in the end of the piece, so that it slopes back into the wall.
A mitered return is another approach that gives you a more finished look. On a mitered return you put a small piece of trim on the end of the board so that the end appears to be molted to match the face. Cutting the joint is pretty easy on a miter saw; gluing a tiny piece onto another can be a bit tricky, but masking tape makes a great clamp.
This guide highlights the procedures for cutting and installing moulding with a mitered return cut.
WHAT YOU NEED FOR THIS PROJECT
Sometimes, putting the molding where you want it means you run into an obstruction, such as an outlet. If so, put a "mitered return" on the end of the molding. Start by choosing a point near the obstruction where you want the molding to end. Mark it with a pencil, and measure the distance from there to the corner of the wall.
Mitering leaves one side of the board longer than the other. Miter the end near the obstruction, creating a board on which the front is slightly longer than the back. Cut the other end square so the front will be the length you measured in step one. If you're coping the end without the return, cut the cope first, then miter.
You won't need much molding for the second piece, but make sure you've got enough to keep your fingers away from the blade - cut a piece that's at least 18 inches long.
Draw a line with your square that begins at the back edge of the miter and comes to the front of the molding. Using a utility knife to mark the cut results in a very precise cut line and a more accurate cut.
Make a cut along the line, positioning it so that you're cutting off the entire miter. To cut precisely, make a shallow cut starting well on the waste side of the line, and slide the board until the blade just touches the line. Cut at the line to cut off the miter. This will be the return you put on the other molding.
Glue the return in place before you install it. Apply glue to both mitered surfaces, as shown, and wipe off the excess with your finger. Fit the pieces together.
The return is far too small to clamp. Hold it in place instead with masking tape. Apply tape to the back, pull it tight over the return, and keep it taut as you attach the tape to the front.
On hefty moldings you can reinforce the joint with a finishing nail or wire brad. On smaller moldings, driving a nail through the thin section will split it, so drive the nail only through a thick section, if at all. Drill a pilot hole for the nail, using the nail as a drill bit, and then nail the pieces together.
Put the molding on the wall, and nail it in place. If the return is more than a few inches from a stud you can nail into, apply construction adhesive to the back of the molding first.