What To Know About Miter Saw Blades

Miter saws are popular tools among professionals and DIYers for good reason. They let you precisely cut a variety of materials, helping complete work quickly and safely.

But even the best saw will only cut as well as its blade allows. Most miter saws ship with a blade that’s good but not great. When you’re ready to upgrade that starter blade, or seek a specialty blade for specific materials, here’s what you need to know.

Miter Saw Blade Basics

Two key features separate miter saw blades available online or at your local home improvement store: diameter and number of teeth. These, along with bore size, are the primary characteristics to consider when choosing the best miter saw blade for you.

Blade size: The most common diameters are 10-inch or 12-inch, with smaller trim miter saws using 7-1/4-in. or 8-1/2-in. blades. Other sizes are more rare. Never use a different size blade than the one recommended for your saw; it’s unsafe and inefficient. The revolutions per minute (RPM) won’t be accurate, and it’s unlikely to cut as well as it should.

Teeth: While the blade is important, the teeth do the actual cutting. Blades are described by number and material. In general, higher tooth count blades give a finer finish with less tear out, but cut slower than blades with fewer teeth. Some blades are made of the same steel as the blade body (also called the blade “plate”). Others have tungsten carbide tips mounted on the teeth. Carbide tipped blades normally last longer and can be resharpened more often.

Arbor/bore size: Miter saw blades have a hole in the middle called a bore. The bore hole slips over the saw’s arbor and is then locked in place. (Some manufacturers use different terms such as “mandrel” or “blade mount.” For the sake of simplicity, we’ll stick to arbor and bore.) Most 10-inch saws have a 5/8-inch arbor, while 12-inch saws have a one-inch arbor. That’s not universally true, so double-check the arbor size before buying blades. If you find a great deal on a blade with a smaller bore size than your saw, look for an adapter that fits your arbor or the blade bore.

Advanced Miter Saw Blade Details

For most DIYers, blade size, tooth count and arbor size are all you need to know to buy a miter saw blade. But they aren’t the only factors to consider. Here’s a set of next-level details, and good default options if can’t devote the time to become an expert.

Tooth geometry: Tooth profile also affects how the blade cuts. Carpenters and saw aficionados can spend hours debating tooth geometry and what shape is best for any given job. If you research this, you’ll encounter a bewildering set of terms like Alternate Top Bevel (ATB), Alternate Top Bevel with Raker (ATBR) and California Triple Grind (CTG). These various profiles (sometimes called “grinds” because they are ground into the tooth) affect how the blade digs into the work material and how easy it is to resharpen.

If all that makes your head spin, stick with an ATB profile on your miter saw blades. The alternating angles create a sharp, precise cut that’s perfect for the most common use of a miter saw: cross-cutting wood. In general, most affordable blades for DIYers have an ATB pattern. You can always look deeper into this topic if you do more frequent miter saw cuts or find you need extremely tight precision.

Hook angle: Although related to tooth geometry, the hook angle is a much simpler concept to grasp. If you look at the tip of each tooth, you’ll see that it leans slightly forward or backward. That lean is the blade’s hook angle, and it usually ranges from five to 20 degrees in the positive direction (toward the blade’s spin) or up to five degrees backward (away from the blade’s spin). The higher the hook angle, the more aggressive the blade is with the work material, pulling it in the direction of the blade spin. For most DIY use, miter saw blades do best with a hook angle of five to 15 degrees. (Higher hook angles are appropriate for table saws, where that pressure will compress the wood against the table top.)

Gullet size: This is the slight dip in front of each saw tooth. The bigger the gullet, the more waste will be removed from the work material. Large gullets are common on table saw ripping blades. But for most DIY-level miter saw blades, the gullet size won’t be much of a consideration. However, if you’re making cuts and notice the blade warming up, or the cutting speed has slowed, check the gullets. If they’re clogged with sawdust or debris, move to a blade with fewer teeth or deeper gullets.

Blade material: The blade plate is made of hardened steel. There are some pros and cons to different kinds of steel, such as stainless steel’s rust resistance or high-speed steel’s performance at high temperatures). But most blades in the DIY price range don’t list the blade material on their packaging, preferring to simply note whether they are carbide-tipped. For DIY use, the blade material is less essential than the other factors on this list.

Kerf width: This is the width of the cut — the blade plate plus any additional material removed by the teeth. (This is why tooth geometry matters. Two blades may have the same thickness, but the blade with teeth that sits out at an angle will create a wider kerf.) Narrow kerf blades reduce chipping, good for plywood and laminates.

Stabilizer vents: Miter saw blades generate a lot of heat, enough for the blade to expand during use or dull the teeth prematurely. Some blades have squiggly lines and holes cut in their body. These “stabilizer vents” allow hot blades to expand without warping, and help reduce overall heat generation. Some stabilizer vents even reduce noise. Laser-cut stabilizer vents tend to perform slightly better than stamped stabilizer vents. The manufacturer will usually use “laser-cut” as a bragging point on the packaging, and laser-cut vents will typically be thinner and more intricate. Although how much any stabilizer vent impacts performance depends on the blade design and what material you’re cutting, it’s always a nice feature to have on a blade.

Other Miter Saw Blade Shopping Tips

Keeping it simple: If all these details are overwhelming, remember that the key features are almost always right in the name of the blade: the blade size and number of teeth. If these two features are all you’re aware of, you’ll probably be fine. For details like tooth geometry and kerf size, look at the blade itself. Many manufacturers print images on the body of the blade that clearly show the hook angle, kerf width and tooth geometry. Get in the habit of looking at these when you use a new blade and you’ll quickly learn what features work well for you.

Blade names: You may notice circular-shaped blades can be listed at retail stores under “circular saw blades,” “table saw blades” and “miter saw blades.” That’s because the blades can be swapped out between all these types of saws, as long as the blade size and arbor size are compatible. However, not all blades are equally useful in a miter saw. In general, blades described as intended for “ripping” cut along the wood grain, something you’ll rarely do with a miter saw. (You won’t be in danger if you use a ripping blade on a miter saw; it just won’t cut as efficiently as one designed for cross cuts.)

Metal saw blades. While blade shopping, you’ll likely see abrasive disc blades for cutting metal. While it’s possible to mount one of these discs onto your miter saw, they’re intended for metal chop saws. A miter saw spins at much higher RPM than a metal chop saw. That speed, combined with the density of ferrous metals, can result in excessive temperatures — high enough to overheat the engine or warp the plastic body of the saw. Stick with metal-cutting blades for miter saws. These specialty blades usually have a hook angle of zero or negative degrees, and work well with non-ferrous metals. For ferrous metals such as iron use an angle grinder or metal saw.

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