Install crown molding like a pro

Q: I am remodeling my living room and would like to install a wide cove molding at the ceiling, but I need help in mitering the corners. Do I cut them at a 45-degree angle? Do I cope them? Any information would be greatly appreciated. --

A: Crown molding is one of the most attractive and interesting molding features you can add to a room. It is also, however, one of the more difficult finish carpentry tasks to undertake.

Crown molding sits at an angle to the wall, as opposed to a base molding that sits flat against it. Therefore, you have to deal with a compound miter -- one that angles in two directions at once -- as opposed to the standard miter used on a baseboard. You have several options open to you for how to do this, and I would recommend that you purchase some inexpensive, paint-grade crown molding to practice with until you get the hang of the techniques. Some of these techniques are also very difficult to explain in words, so your best bet is to purchase a book on finish carpentry (or get one from the library) that has illustrations of the various step-by-step procedures that follow:

Compound miter saw: If you have access to one, the easiest way to cut crown molding is with a compound miter saw. These saws have the ability to be set at an angle relative to the back fence as well as having the head of the saw set at an angle, allowing you to cut both angles at the same time. Full instructions for the proper angle settings are included with the saw (they differ with the type of crown molding being installed). If you have a lot of molding work to do you may want to invest in one, or they can also be rented.

Table or radial arm saw: You can also make compound miter cuts on a table saw by tilting the blade and then holding your molding against a miter gauge that's set at an angle. Table saws, however, tend to be awkward for handling long pieces of molding. You can also use a radial arm saw by angling both the arm and the blade, but I've found the cuts on these to be somewhat rough.

Standard miter saw and miter boxes: You can use a standard miter box or miter saw to cut crown molding. The trick is to cut the molding upside-down, and with both of the rear faces in perfect contact with the fence. In other words, the molding is upside-down and facing you, with the ceiling edge down and against the bottom of the miter box and the wall edge up and against the back of the box. You can then make the cut with the blade set at 45 degrees.

Coping: This is done by first square cutting the end of one piece of molding and running it all the way into the corner, then cutting the end of the intersecting one in a pattern that matches the face of the first piece. This is not as difficult as it may seem, but it does require some patience and the use of a relatively inexpensive hand tool called a coping saw.

Corner blocks: If you don't want to mess with angles at all, you can instal
l decorative corner blocks at each inside and outside corner, then simply square-cut the molding and butt it against the flat sides of the blocks. Corner blocks are not a stock item at most stores, so ask to see a molding catalog to find out what's available.

By the way, with whatever technique you decide on, crown molding is considerably easier, safer and more accurate to install if you have the help of a second person.

Published by Paul Bianchen - Inman News