For most DIYers, fitting baseboard moldings on the interior corners of the room is best accomplished with miter joints—45-degree miter cuts to each adjoining piece of molding. When fit together, these corners make 90-degree angles. But room corners sometimes vary slightly from perfect 90-degree angles, and professional trim carpenters have a number of tricks they use to ensure that baseboard moldings fit perfectly. The technique described here, modified for DIYers, will also work for other trim moldings, such as door and window case moldings, or chair rail moldings.
Before You Begin
Cutting trim is best done with a power miter saw fitted with a good fine-tooth trim blade. General-purpose construction blades are too coarse to produce the very smooth cuts you want when fitting trim joints.
Power miter saws are now so affordable that any DIYer can own one, and so versatile that all DIYers should have one. But if you have a manual miter box and backsaw, it is entirely possible to cut miter joints with this setup.
Another exceedingly useful tool is a power brad nailer. These tools come in several types, including pneumatic nailers powered by small air compressors, corded electric nailers, and cordless nailers that operate with batteries. Like power miter saws, brad nailers are extremely versatile and will quickly pay back your investment.
Although it may feel a little awkward, it is best to operate the saw blade with your "opposite" hand when the orientation of the baseboard requires it. It is possible to cut the trim upside down in order to always use your favored hand, but this can often lead to cutting mistakes. The best method is to position the baseboard on the saw in the same direction as it will sit on the wall. And NEVER cut "cross-handed" by trying to operate the saw with your "good" hand while reaching across the saw to hold the baseboard with your other hand. This is a very dangerous practice.
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Equipment / Tools
- Tape measure
- Power miter saw
- Eye protection
- Stud finder
- Hearing protectors
- Power brad nailer
- Baseboard molding
- Painter's tape
- 1 1/2-inch brads for power nailer
Mark Direction of Cut on First Baseboard
Press the squared-off end of the first baseboard piece tight into the corner along the floor.It doesn't matter if you begin with the left or right side; in our example, the first piece is on the right side. Use a pencil to make a direction line on the top of the baseboard, marking at a roughly 45-degree angle from the inner corner outward toward the face of the baseboard. This will help you orient the piece of trim on the miter saw before you cut it. It's surprisingly easy to get the direction wrong when you are cutting many pieces of trim.
Set the Saw Angle
Move the miter saw's blade to an angle just slightly less than 45 degrees to the back fence. While it might seem as though 45 degrees is the perfect angle to achieve 90-degree corners, just a fraction of a hair less than 45 degrees (but no less than 44 degrees) produces a better fit when you fit the two adjoining pieces of baseboard.This is because room wall surfaces usually are slightly rounded off where they meet in the corners, falling short of being perfectly square.
You can use smaller pieces of about 6 inches with opposite 45 degree angles to test-fit corners. If the corner is open on the face, slightly decrease the angles on the actual pieces; if it's open at the back, slightly increase the angles on the actual pieces.
Cut the First Piece
Position the piece of baseboard on the saw table so that the back of the trim is tight against the vertical fence of the saw. You may need to support the end of the baseboard so it rests flush against the table. Orient the baseboard in the same way as it will fit in the room—think of the table of the saw as the floor, and the fence of the saw as the wall against which the baseboard will fit.
Before starting the saw, momentarily pivot the blade down so it just touches the baseboard and make sure it is oriented in the same direction as the marked line drawn on the top of the baseboard.
Wear eye protection and hearing protectors when cutting with a power miter saw. Power up the saw, then lever the spinning blade down through the baseboard using a smooth motion. Make sure you are tightly gripping the baseboard with your free hand. Some saws have clamps you can use to secure the baseboard against the fence and table.
Clean up the Cut Edges
The saw blade may leave small splinters along the cut edge of the miter. And if you are using plastic baseboards, there may be burrs of melted plastic left along the edges of the cut.
After the baseboard cools down from the friction of the blade, snap off any splinters or plastic burrs that remain on the edges of the cut. Or, lightly scrape the edge with the blade of a utility knife.
Reverse the Saw Blade
Pivot the saw blade to the opposite direction, again setting it to an angle just slightly less than 45 degrees. This will allow you to cut the adjoining piece of baseboard.
Cut the Adjoining Baseboard
Mark and cut the adjoining piece of baseboard, using the same technique. Again, clean-up splinters or plastic burrs from the edges of the cut once the baseboard cools down.
Mark the Straight Cuts
The easiest way to mark the opposite ends of the baseboards for the straight cuts that will fit against door moldings is to position the baseboard in place and mark where it will fit against the case molding. Where this method is not practical, you can also use a tape measure to determine the cutting length.
Set the miter saw at a square 90 degrees, then cut the baseboard pieces off square where they will fit against case moldings or other obstructions.
Test-Fit the Baseboards
Position the baseboards in place to test the fit. The miter joint should fit tightly together with no appreciable gap between pieces.
If the angles prove to be wrong, you may be able to carefully re-trim the ends of the board, making slight adjustments to the saw angle. But avoid the temptation to fill large gaps with wood filler or caulk, since these patches will eventually come apart due to seasonal expansion and contraction. It is generally better to recut new pieces of baseboard with adjusted miter angles to accommodate a corner that is badly out of square. Usually, you can get by cutting one adjusted piece rather than both baseboards.
Find and Mark Wall Studs
With a stud finder, locate the wall studs and mark their locations with small tabs of painter's tape. Studs usually run every 16 inches on-center. You won't need to locate studs in corners, as studs are always found there.
Nail the Baseboards in Place
Tack the baseboard into place by shooting brads at an angle into the wall where the studs are located. Between the nails driven into the studs, alternate with nails positioned near the bottom of the baseboard, so they drive into the wall's soleplate. After driving the first brad, carefully examine the head of the brad to make sure it is slightly recessed below the surface of the baseboard. If necessary, adjust the tool to change the penetration of the brads.
Traditionally, trim molding was nailed by drilling pilot holes, driving finish nails with a hammer, then "setting" (recessing) the nail heads using a nail set tool. But a power brad nailer—whether operated by compressed air, batteries, or power cord—makes this work far easier and more accurate. A brad nailer will have limitless uses around the house, so it is well worth buying this tool if you don't already own one.
Trim carpenters and other professionals often prefer coped joints because they tend to open up less than miters when the wood shrinks during dry weather. Coped joints also accommodate out-of-square wall corners better than miters, which require a 90-degree corner for a perfect fit.How do you handle baseboard trim with a miter saw? ›
Start with cutting a reverse 45 degree angle on the base. You'll follow that profile to cut out allCan you cut baseboards with a miter saw? ›
Once you have set the miter angle and bevel angle, and you have the baseboard on the cutting table of the miter saw, you can turn the saw on. Hold the handle of the saw with one hand, hold the baseboard securely in place with the other, and then move the blade down through the wood until the cut has been made.What kind of miter saw do I need for baseboards? ›
TACKLIFE 10-Inch Sliding Compound Miter Saw is one of the best choices for cutting your baseboards. With two adjustable speeds and three blades. By pressing the switch, you can convert between the two speeds (3200 RPM or 4500 RPM) effortlessly for more precise cutting, high speed for wood.Should inside corners be mitered? ›
For most DIYers, fitting baseboard moldings on the interior corners of the room is best accomplished with miter joints—45-degree miter cuts to each adjoining piece of molding. When fit together, these corners make 90-degree angles.Should I cope or miter inside corners? ›
Coping is better than mitering at inside corners. But on tall baseboards, cutting the long, straight section of the cope with a coping saw is difficult, and the cut is usually wavy.Do you cut baseboard flat or vertical? ›
What??? Pros Cut Baseboard Upside-down and Vertical... Why?What degree do you cut baseboards? ›
Use a miter saw to bevel cut the end at a 45-degree angle. The cut will reveal the profile of your baseboard. With a coping saw, cut along the profile. Slightly angle the blade so that you cut away from the backside of the baseboard.What blade should I use to cut baseboards? ›
Despite miter saws being the best option for cutting baseboards, the blades they come with are often not designed for trim work. Instead, many professionals upgrade to 60-tooth blades.Is a 10 or 12-inch miter saw better? ›
12-inch miters with blades of the same breadth are sturdy and last longer since they are built for heavy-duty cutting. Using a larger saw will allow you to cut through more wood. You can cut through 4x6s with a 12-inch saw in one pass. Harder materials like plywood might also benefit from the greater sizes.
Miter saws are the best choice if you need to cut a lot of angles; for example, when cutting baseboards, crown molding, trim for cabinets, or when building furniture.Which is better 10 or 12 miter saw? ›
You can put your 10-inch blades on your 12-inch saw (assuming the arbor holes are the same size), but you cannot put 12-inch blades on a 10-inch saw. The 12-inch saw gives you greater versatility – with the larger blade, it's the hefty workhorse, and with the smaller blade, it's a master of precision.Why are my 45 degree cuts not lining up? ›
This can happen even if you get the 45 degree cut spot on. Usually if you still can't get the miter joint to close perfectly, it's because you either cut one piece too long (or too short), or the blade itself was not perpindicular (90 degrees) from the base.How do I know what angle my baseboard is? ›
How To Get The PERFECT Miter Angle On Baseboard EVERY TIME ...How do you cut 45 degree baseboard? ›
How to Cut Baseboards for a 45 Degree Angle - YouTubeHow do you Mitre baseboard corners? ›
A Simple Trick to Install Baseboard Corners Perfectly - YouTubeHow do you butt joint a baseboard? ›
How to Attach 2 Pieces of Baseboard or Chair Rail with a Scarf JointShould I cope or miter crown molding? ›
A cope is a much better joint and can be quicker than mitering. You can pressure fit a coped joint. It will not open up when you nail it and it will stay tighter longer. The way to make copes faster than mitering is to use the Copemaster, a new machine that works like a key coping machine.Do you need a coping saw for baseboard? ›
Coping a baseboard is a carpenter's technique that is used to join two pieces of wooden molding at inside corners for either baseboard or crown molding. Plus, this technique works great for chair rails and picture rail molding. Coping baseboard requires two steps, a miter saw, and a coping saw.How do you handle baseboards without a coping saw? ›
Instead of using a coping saw, learn to cope baseboard with a miter saw. It's faster and works great for common baseboard profiles.
How to splice baseboard or trim DIY video #diy #baseboard #trim #spliceDo you paint baseboards before installing? ›
If the baseboards have not yet been installed, you should always paint the baseboards before installation. Minor damage to the paint finish will occur during installation, but this is expected. With most of the painting already done, you'll only need to do a small amount of touch-up after installing the baseboards.What type of baseboards are in style? ›
Solid wood finger jointed wood, and MDF (medium-density fiberboard) baseboards are among the most popular material choices. Choosing the material often comes down to budget or color preference, so it's easier to determine which material is right for your house.How much does it cost in labor to install baseboards? ›
Labor Cost to Install Baseboard Trim
As with the labor cost to install trim throughout your house, the labor cost to install baseboards is $4.90 to $7.75 per linear foot. Baseboard materials are pretty inexpensive (only about $0.60 to $1.20 per linear foot). Labor makes up most of your price.
What gauge nails to use for baseboards? Based on nail size, you should be looking for anything between 15 gauge and 18 gauge. With these gauges it you can easily find nails up to 2.5'' long which is an ideal length for baseboard nails.What nails do you use for baseboards? ›
Finish nails are used for interior and exterior trim, window and door casing and chair rails. They're ideal to fasten baseboards and crown moulding too. You'll also find finish nails on stair treads and risers, as well as part of general light carpentry and cabinets.Can I use a brad nailer for baseboards? ›
Q. Can you use a brad nailer for baseboards? Brad nailers are suitable for baseboards. Most fire brads as long as 2 inches, which is enough to penetrate a 3/4-inch thick molding, 1/2-inch thick drywall, and bite into the framing lumber in the baseplate or wall studs.How many teeth blade for cutting trim? ›
A 40-tooth blade works fine for most cuts through plywood. Blades with 60 or 80 teeth should be used on veneered plywood and melamine, where the thin veneers are likely to blow out on the underside of the cut, a characteristic known as tearout. MDF requires even more teeth (90 to 120) to get the cleanest cut.How many teeth do you need for trim? ›
To achieve the smoothest miter saw cuts for furniture building, cabinetmaking, and trim work, you need a blade with a lot of teeth. A stock 12-inch blade typically has 32 teeth. A good trim blade commonly has 80.Is more teeth on a saw blade better? ›
Number of Teeth
Generally, blades with more teeth will provide a smoother, finer cut whereas blades with fewer teeth will provide a rougher cut. The benefit of fewer teeth is faster cutting and a lower price. For most construction work, a 24-tooth general use blade is sufficient.
How to Use A Miter Box - YouTubeHow do you miter corners on baseboard trim? ›
perfect inside miter joint hack - baseboard molding install - YouTubeHow do you cut 45 degree baseboard? ›
How to Cut Baseboards for a 45 Degree Angle - YouTubeWhat type of saw do you need to cut trim? ›
A miter saw is a perfect tool for cutting moulding or wood trim. Miter saws have a gauge on the saw table that lets you set the saw to make accurately measured angle cuts.How do you cut perfect corners for molding? ›
A Simple Trick to Install Baseboard Corners Perfectly - YouTubeHow do you get the perfect miter cut? ›
How to Make Perfect Miter Cuts - YouTubeHow do you measure an angle for baseboards? ›
How To Get The PERFECT Miter Angle On Baseboard ... - YouTubeHow do you cut baseboard corners without a miter saw? ›
A circular saw is a versatile tool that can be used to cut pieces of trim for both molding joints or a specific angle cut by adjusting the angle bracket of the circular saw. You can cut both wide or low profile baseboards using both square and straight bevel cuts, and this tool is perfect for it.How do you use Bevel for baseboards? ›
Lay the T bevel against the surface of the angle cut to be copied. Rotate the inside edge of the blade to the existing angle until it matches the angle being transferred. Tighten the wing nut until it locks the blade and handle in position. Place the T bevel on the working surface and transfer the angle.How do you join baseboards? ›
How to Attach 2 Pieces of Baseboard or Chair Rail with a Scarf Joint
Things You'll Need
Installing wood trim is one of the final jobs in finishing the interior of the home. Its job is to provide a smooth transition between walls, windows, and flooring. When cutting trim for 90 degree corners, you are required to cut each board with a 45 degree cut.
How To Cut Perfect Miters - YouTubeHow do you cut a 45 degree baseboard with a circular saw? ›
How to Cut a 45 degree Angle with a Circular Saw - YouTubeWhat saw is best for baseboards? ›
Miter saws are the best choice if you need to cut a lot of angles; for example, when cutting baseboards, crown molding, trim for cabinets, or when building furniture.Which hand saw is best for cutting molding? ›
Coping saws are popular for cutting molding and baseboards. When finalizing a trim job, precision is integral for a professional result. Because of its fine blade, deep throat, ease of use, and ability to saw at multiple angles, a coping saw can make the difference between a sloppy or a well-done trim job.What is the easiest saw to use? ›
We usually recommend a miter saw for beginners. It's very easy to use and you can make several projects with just this saw. Coming in as a close second for the best saw for a beginner is a circular saw because it's so versatile.