Installing crown molding is one of the more difficult aspects of finish carpentry. Crown molding is typically used in a couple different situations.
One of the more apparent situations where you might see crown molding is installed at the tops of kitchen cabinetry. Another place is at the top of walls where a wall meets the ceiling. Both applications add character and do a good job of dressing up a room. Here are a few quick tips for installing crown molding that will help if you have never done a project like this.
Crown molding is not as difficult as it seems. One key thing to remember is to hold the molding on the miter saw the same way it gets nailed up and installed. What this means exactly is: crown molding will have a flat section of the profile on the bottom of the molding that is nailed flat against the wall or cabinet. This flat section has to be held flat against the fence on your miter saw.
Some finish carpenters will disagree with this because there are other ways to cut crown molding but I have learned that this is the easiest and best way for inexperienced people. The only draw back to this method is being able to hold the molding securely against the fence the way it gets mounted. If it is not exact, the angle changes at the cut slightly and an open miter at the corner is the result.
For inside corners there are two ways to get through the corner. One way is to run the first piece into the wall or corner flat and even just as if the crown molding would end right there. Then use the coping method to take off from the corner.
This is a neat looking corner and provided you took your time and made a nice cope it will flow through the corner as if there wasn't a joint.
The other way is to cut the inside angle on both pieces and to butt them together at the joint. There is nothing wrong with this type of joint and if you find its easiest then use this method and keep the miter tight at the joint.
The trick here is to use the trial and error method. Cut yourself two short pieces of crown and let's say it's a 90 degree inside corner, try cutting two 45 degree inside angles too these short pieces and trial fit to see how they butt together at the joint.
Adjust the angle on the saw as necessary and keep trial fitting until the correct angle is set to achieve a tight miter with these short pieces. Then when you are confident the angle is correct cut the actual pieces of crown that will be installed.
Always use wood glue at the joints and the outside corner joints should be pinned together with small nails. It's easiest and quickest to be installing crown molding with some type of small nail gun. I use an 18 gauge nail gun for installing crown molding.
It's best to have someone helping for a project like this. Sometimes when installing this crown molding at the ceiling corner of a room the ceiling may have some uneven areas and the crown won't be tight against the ceiling.
One way to combat this is to caulk these areas with paintable caulk and it will look just fine as long as the gaps aren't too big. Installing crown molding is like any other thing, the more you do the better you get.