Crown Molding Made Easy
By Rockler Content Team
Monday May 10, 2004
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
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
1. 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
4. It's incredibly easy to set up and use, and requires no expert
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...
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.
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
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
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.
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.
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:
* Dentil Molding
* Rope Crown Molding
* Rope Accent Crown Molding
* Crown Molding
* Double Dentil Molding
Rockler item #53530
Suggested Tools and Supplies
* #67626 Rockler Crown Molding compound miter jig
Chop Saw (a compound miter saw is not necessary)
Crown Molding & Trim Book with True Angle checker set
* 10'' x 80 Tooth saw Blade
* #24980 Multi-Quick support for molding
Titebond Molding glue (gives you time to make adjustments).