Cutting Crown Molding Angles

What You'll Need
True angle protractor
A miter jig
Measuring tape
Safety goggles

Crown molding angles are classic accents meant to fit any seamed space. Though they are most commonly seen on the space between ceilings and walls as an architectural trim, smaller versions can be placed on furniture and cabinetry. These angles need precision when cutting to meet the demands of the splices involved not to mention the inside and outside corners. Though not rampantly known as a DIY project due to its cumbersome nature, cutting this type of molding can still be done.

Step 1 - Take Measurements

Accuracy is key in the cutting of crown molding as all the corners have to meet perfectly. Use the tape measure to determine how much crown molding you will need. Measure the wall length first then the crown molding pieces. Inadequate readings will require you to include additional joints on straight surfaces due to shorter pieces, which will in turn distort the overall appearance of the molding. These measurements will also help you ensure that you do not create gaps where the corners meet, which will not be able to fit into the space. Use the true angle protractor to determine the angle corners now that room corners vary in angles.   

Step 2 - Cutting the Crown Molding

Once the measurements have been noted, place the piece of molding on a table and use a miter saw to make the cuts. You can choose between the power miter saw and the hand miter box. Consider the width of your molding when choosing your saw as this will determine whether your saw will be able to extend beyond the width of the molding.  

Also known as the ‘nested’ method, this method comes with the advantage of no bevel adjustments as you will only need to adjust the miter saw with the molding lying flat.

Step 3 - Cutting the Crown Molding Using a Jig

This is the latest improvement in crown mold cutting as it eliminates guesswork. The jig, in this case the compound miter jig, will create the precise angle needed for accurate installation.

First, create a template using a 2-foot long piece of your molding. Label this the ‘inside’; then place it in the jig with the bottom part up as every cut made on the molding must be done so with the bottom part closest to the blade. After adjusting the fence, the top of the molding should form a 90-degree angle where it meets the sliding fence. Tighten the jig’s knob to lock your setting.

Divide the angles you had taken of your wall corners by 2 then set your jigsaw according to this number. Place your molding on the bed and make the cuts.

There are four types of cuts that can be made using the jig. Inside left, inside right, outside right and making a splice to join 2 lengths of molding on a long wall. Video tutorials are available to help you create these.  

Step 4 - The ‘Flat’ Method

This is a far more difficult method and in most cases, a rare method to incorporate when cutting your crown molding. Because crown molding angles are very difficult to set accurately, this method should first be tested on scrap molding, using a crown molding calculator as you go along.