How to cut crown molding
Cutting crown molding requires precise angle cuts, typically 45-degree miters for inside and outside corners. Specialized jigs or techniques like cutting on the flat can simplify the process. Ensure your saw is set correctly and practice on scrap pieces before making final cuts.
Cutting crown molding can seem intimidating, but with the right tools and techniques, you can achieve professional results. The most common cuts are miter cuts for corners. You’ll need a compound miter saw for the cleanest and most accurate cuts. A good quality tape measure and a pencil are also essential.
Before you start cutting, understand how crown molding is installed. It sits at an angle between the wall and the ceiling. Standard crown molding has a spring angle of 38.5 or 52 degrees, which dictates the angle you’ll cut.
The most crucial step is setting your compound miter saw correctly. For most standard crown molding, you’ll set the saw to a 45-degree miter angle. The ’tilt’ or bevel angle is often overlooked. Many saws have a detent or setting for crown molding, usually around 31.6 degrees for standard 38.5-degree spring angle molding when cutting it upside down. However, cutting it ‘on the flat’ is often easier for beginners and requires different saw settings.
Cutting crown molding for inside corners
For inside corners, you need to cut two pieces that meet at a 90-degree angle. Each piece will have a 45-degree miter cut. When viewed from the front, the longest point of each miter should meet the corner.
The most common method is to place the molding upside down on the saw with the back against the fence. Set your saw to a 45-degree miter. For a left-hand cut, the molding’s edge will be against the fence to your left. For a right-hand cut, the molding’s edge will be against the fence to your right. Ensure the saw blade cuts the ‘inside’ edge of the molding.
Alternatively, you can cut crown molding on the flat for inside corners. This involves setting the molding face up on the saw, against the table. You’ll need to set both the miter and bevel angles. A common setting for a 45-degree inside corner when cutting on the flat is a 31.6-degree bevel and a 45-degree miter. This method is often preferred because the molding is stable and easier to manage.
Cutting crown molding for outside corners
Outside corners are the reverse of inside corners. You’ll still make 45-degree miter cuts, but the long points of the molding will extend outwards from the corner.
When cutting upside down, place the molding with its back against the fence. Set the saw to 45 degrees. For a left-hand outside corner, the molding’s edge will be against the fence to your left. For a right-hand outside corner, it will be to your right. The saw blade will cut the ‘outside’ edge of the molding.
Cutting outside corners on the flat also requires specific saw settings. For a 45-degree outside corner, you’ll typically use a 31.6-degree bevel and a 45-degree miter, but the saw head will be on the opposite side compared to an inside corner cut. Always measure and mark your cuts carefully to ensure the molding meets cleanly at the corner.
Cutting crown molding on the flat
Cutting crown molding ‘on the flat’ means laying the molding flat on the saw’s table, rather than holding it against the fence in the upside-down position. This method can be more stable and easier to visualize for many DIYers.
To cut on the flat, you need to set both the miter and bevel angles on your compound miter saw. For a standard 45-degree corner, you’ll typically set the miter angle to 45 degrees. The bevel angle is crucial and often set to 31.6 degrees for common 38.5-degree spring angle molding. Always check your molding’s spring angle and consult your saw’s manual.
When cutting on the flat, ensure the molding is securely supported. You might need additional supports or clamps. Remember that the cut piece will have its back facing upwards on the saw. This technique simplifies managing the molding’s profile and reduces the risk of it shifting during the cut.
Using a coping saw for inside corners
While miter cuts are standard, coping is often preferred for inside corners, especially with older homes where walls may not be perfectly square. Coping involves cutting a precise profile on one piece of molding to fit snugly against the face of the other piece.
First, make a straight miter cut on both pieces of molding intended for the corner, usually at 45 degrees. Then, fit one piece into the corner and mark where it meets the wall. Cut the second piece with a 45-degree miter, but with the back cut away so the front edge protrudes slightly. Use a coping saw to carefully cut along the profile of the molding, creating an L-shaped edge that fits over the mitered edge of the first piece.
This technique requires a steady hand and a sharp coping saw. Practice is essential to get a tight fit. The goal is to have the back-cut piece’s profile rest perfectly against the face of the first piece, creating a seamless look that hides any imperfections in the wall angles.
Tools and materials needed
A compound miter saw is the most critical tool for accurate crown molding cuts. Ensure it has a detent system for common angles and a good blade for clean cuts.
You will also need a reliable tape measure for accurate measurements and a pencil for marking.
A coping saw is essential if you plan to cope joints for inside corners. Safety glasses are a must for eye protection.
A stud finder might be useful for locating studs for secure mounting, though this is more for installation than cutting.
For cutting on the flat, consider using clamps or additional supports to keep the molding stable on the saw table.
Common Crown Molding Cutting Mistakes and How to Avoid Them
| Step or Tool | Typical Mistake | How to Avoid It |
|---|---|---|
| Measuring | Incorrect length measurements | Always measure twice. Account for the miter angle – the actual length along the wall will be shorter than the molding’s longest point. |
| Miter Saw Setting (Upside Down) | Molding slips, inaccurate angle | Ensure the molding’s back is firmly against the saw’s fence. Use painter’s tape to secure the molding if needed. Double-check the 45-degree miter and the appropriate bevel angle (usually ~31.6 degrees). |
| Miter Saw Setting (On the Flat) | Bevel or miter angle is wrong | Confirm the spring angle of your molding. Set both the miter (45 degrees) and bevel (typically 31.6 degrees) angles precisely. Use a protractor to verify if unsure. |
| Cutting | Jagged or rough cuts | Use a sharp, fine-tooth blade designed for molding. Make cuts smoothly and avoid forcing the saw through the material. |
| Coping | Profile cut is too deep or shallow | Practice on scrap pieces. Cut slowly and aim for a snug fit against the adjacent piece’s face. The coping saw blade should be set to a slight angle. |
| Final Fit | Gap in corners | Make small adjustments with a file or sandpaper after cutting. Recut if the gap is significant. Ensure you’re using the correct inside/outside corner cut. |
FAQ
How to do crown molding
Install crown molding by first cutting your pieces with precise mitered ends to fit corners. Use construction adhesive and finish nails to attach the molding to the wall and ceiling. Ensure a tight fit in the corners, using coping for inside corners if walls are uneven. Caulk and paint for a seamless finish.
How to cut crown molding for corners
For corners, make 45-degree miter cuts. For inside corners, the long points of the molding face outwards. For outside corners, the long points face inwards. Place the molding upside down on the saw with the back against the fence, or cut it on the flat using appropriate bevel and miter settings.
How to cut crown molding on the flat
To cut crown molding on the flat, lay the molding face up on the saw table. Set your compound miter saw to a 45-degree miter angle and typically a 31.6-degree bevel angle. Ensure the molding is stable and secure against the saw’s fence and table before cutting.
How to cut angles in crown molding
Angles in crown molding are cut using a compound miter saw. For standard 90-degree corners, you use 45-degree miter cuts. The specific bevel angle depends on the molding’s spring angle, often around 31.6 degrees for common profiles when cutting upside down or on the flat.
How to cut angled crown molding
To cut angled crown molding, you utilize the miter and bevel adjustments on a compound miter saw. Set the miter angle to achieve the desired corner fit (e.g., 45 degrees for a 90-degree corner). The bevel angle accounts for the molding’s spring angle, ensuring it sits flush against the wall and ceiling.
How to miter cut crown molding
Miter cutting crown molding involves setting your compound miter saw to a specific angle, typically 45 degrees for standard corners. You position the molding against the saw’s fence or flat on the table, then make the cut. Ensure the correct face of the molding is oriented for the specific corner (inside or outside).