Crown Molding Made Easy
posted on August 15, 2011 by Rockler

Crown Molding Introduction

Nothing dresses up a room or a cabinet like the regal presence of crown molding. This classical accent defines a project the way a frame embellishes an oil painting. And with such a wide array of profiles available, there's a crown molding made to fit every space. Smaller profiles are used on furniture, casework and cabinetry (like the dentil crown shown at right), while larger moldings are used as architectural trim.

So, why hasn't every do-it-yourselfer rushed to the lumberyard? Well, until now, installing crown molding really hasn't been a DIY project. Cutting compound angles and keeping track of inside and outside corners, all those splices and the molding's various orientations has been such a nightmare that most folks either call a pro, or balk at the cost of doing so.

The biggest problem has always been cutting the angles, rather than the actual installation. There are two reasons for this. Most crown moldings don't actually sit against the wall at 45 degrees, and the corners in your rooms are rarely a perfect 90 degrees.

Two new tools from Rockler Woodworking and Hardware combine to eliminate these problems and make an easy job of cutting and installing crown molding. The first of these, the TRUE ANGLE, is a large acrylic protractor which measures every corner and tells you the exact angle to set your miter saw. (More on this later.)

The biggest news in crown molding installation is the Rockler Compound Miter Jig. By holding the molding on your saw's bed at exactly the same angle that it will be installed on the wall, the jig eliminates all guesswork and confusing math.

Advantages of the Rockler Compound Miter Jig

Crown Molding Compound Miter Jig1. It eliminates the need to cope inside corners. Until now, trim carpenters often installed one piece of crown molding with a 90 degree cut, then used a coping saw to cut the actual profile of the molding on the second piece so it would fit tightly against the first. Imagine having to make all those complicated cuts, and ruining a long piece of molding with the slightest slip-up. The jig lets you create a true miter in every inside corner: one cut on a power saw does the job.

2. Crown moldings come in so many profiles that few of them sit against the wall at a perfect 45 degree angle. The most common deviation is 52/38 (the top of the molding meets the ceiling at 52 degrees, while the back meets the wall at 38 degrees), but every manufacturer has their own specifications. This has always been one of the biggest headaches in dealing with crown moldings. The jig solves the problem with a single adjustment. Hold the molding in place, slide the fence and lock it. That's it. Do this once for each molding on the job (which usually means once per job) and you can throw away the calculator.

3. The Rockler Compound Miter Jig lets you make compound cuts on a single plane saw (such as a radial arm saw or most older miter saws). You no longer need a compound miter saw to install crown molding.

4. It's incredibly easy to set up and use, and requires no expert knowledge.

5. It adjusts in seconds. Once the jig is set up for your molding, there's no need to change it.

6. The old way of installing crown molding was to have two people each hold a piece of the molding in opposite corners, then snap chalk lines around the room. With the Rockler Compound Miter Jig and a short template that you make from your crown molding, all that work is eliminated.


Setting Up the Jig

1. Before you pick up the jig, make a simple crosscut on your saw to create a 2 foot long piece of your molding to be used as a template throughout the job.

2. To begin setting up the jig, place your template piece in the jig with the bottom edge up. This orientation is very important. Every single cut you make is done with the bottom of the molding closest to the blade. In English pubs, people drink toasts by saying "Bottoms up!", which means they tilt they glasses until the bottom is above the rim, and they drain their beer in one gulp. (Now that you've read that, it will be a lot easier to remember "Bottom's up!" every time you place a piece of crown molding in the jig.)

3. Adjust the fence so that the top and bottom edges of the molding are flush, as shown in the photo at right.. That is, the top of the molding (which meets the bottom of the jig) should form a 90 degree angle where it meets the sliding fence.

4. Tighten the two knobs on the jig to lock in your setting. That's it! You are now all set to make every compound cut required in a standard crown molding installation.

Making the Cuts

There are only five different cuts required in almost any crown molding job. You are either cutting a left or right inside or outside corner, or you are making a splice to join two lengths of molding on a long wall. As you stand in the center of a rectangular room and look into one of the four corners, the piece of molding which will be attached to the wall on the left of the corner is an "inside left". If your room has alcoves, or is L-shaped, you will have at least one outside corner.

Not all corners are exactly 90 degrees. By using the TRUE ANGLE protractor, you can check each angle. Divide the number by 2 (the result will invariably be within a degree or two of 45), and set your saw accordingly for a tight fitting joint every time. Let's make some cuts...


Inside Left

Inside Right

Outside Left

Outside Right

Take the 2 foot long template piece you cut earlier and write "Inside" on it. Now you need to cut an inside right on one end of the template, and an inside left on the other. Let's begin with the inside right.

Looking at the saw, swing the blade 45 degrees to your left. Place the molding in the jig ("Bottom's UP!) and place the jig on the bed of the saw. The bulk of the workpiece should be to the left of the blade. Slide the jig so that the cut will remove a minimum of waste. Make sure the jig is NOT IN THE PATH OF THE BLADE. Without turning on the saw, drop the blade to make sure it misses the jig. Adjust if required. Keep your left hand on the molding inside the confines of the jig (where it is safe), and make the cut.

To summarize: On a right inside corner, the blade is 45 degrees to the left, and the bulk of the workpiece is to the left of the blade.

What's really nice is that you don't have to remember that - it's printed right on the jig (along with the orientations for left inside corners and both outside corners).

Now, let's cut a left inside corner on the other end of the template. Looking at the saw, swing the blade 45 degrees to your right. Place the molding in the jig ("Bottom's UP!) and place the jig on the bed of the saw. The bulk of the workpiece should be to the right of the blade. Slide the jig so that the cut will remove a minimum of waste. Make sure the jig is NOT IN THE PATH OF THE BLADE. Without turning on the saw, drop the blade to make sure it misses the jig. Adjust if required. Keep your right hand on the molding inside the confines of the jig (where it is safe), and make the cut.

To summarize: On a left inside corner, the blade is 45 degrees to the right, and the bulk of the workpiece is to the right of the blade.

When you are cutting actual pieces (as opposed to the template), you may have to make a very slight adjustment to the 45 degrees, depending on how close to 90 degrees your room's corners are. But you'll be pleasantly surprised that almost all cuts will end up working quite well with the saw set to 45 degrees. You now know how to make all your inside and outside corner cuts. The only thing left to cover is splicing. In that case, you place the workpiece in the jig ("Bottom's up!"), set the blade at 45 degrees in either direction, and make a cut at one end of one piece of molding. Then, leave the setup exactly the same and make your second cut on the end of a second piece of molding. As long as the angle of the miter saw blade remains the same, you'll have a perfect splice every time.

Installation

In one hand, hold the end of the workpiece that fits in the corner. In the other hand, hold your template. With the bottoms down, slide them both into the corner and make minor adjustments until you have a perfect fit (no gaps). Nail the workpiece in place - a finish nailgun works wonderfully, and they're cheap to rent. 

If the workpiece is more than a couple of feet long, you'll need a helper. If a live body isn't available, take a look at Rockler's Multi-Quick support. It's very inexpensive and it will hold a length of molding in position while you make minor adjustments and/or nail the piece in place. 

Notes

You'll need to make up three templates - one for inside corners, one for outside corners, and one for splices. They are used as visual checks so you always make the right cut, and also to line up the molding on the wall during installation.

Note that the jig doesn't slide on the bed of your saw once you're set up, or that the molding doesn't slip in the jig. This is in part due to a non-slip material applied to both faces of the back (fixed) fence - a small detail but one you'll be delighted with in the course of the job.

The jig can handle moldings up to 4-7/8" wide (depending on the angles of the top and bottom edges).

Choosing a Crown Molding

To see pictures of various crown molding which can be used in applications such as walls, cabinets and furniture, visit the following links:

Rope Accent Crown Molding  

Suggested Tools and Supplies

posted on August 15, 2011 by Rockler
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What People are Saying:

I have been ordering from Rockler for almost 20 years and have found their products to be very inexpensive and of high quality. Shipping is fast even when an item is back ordered. The best prices I have found anywhere."

- Orval - 08/07/2012

What People are Saying:

I have been ordering from Rockler for almost 20 years and have found their products to be very inexpensive and of high quality. Shipping is fast even when an item is back ordered. The best prices I have found anywhere."

- Orval - 08/07/2012
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