How to Change a Miter Saw Blade

A miter saw is a versatile power tool that can cut through a variety of materials. Get comfortable changing the blade of your miter saw to increase the capabilities of this machine. Learn when and how to change a miter saw blade, how to perform the replacement, and what kind of blade is best for your purpose.

Changing a Miter Saw Blade

The blade of a miter saw can be safely and easily changed by a DIY hobbyist. Here is the process for changing your miter saw blade:

1. Evaluate the blade. A dirty blade may only need to be removed, cleaned, and reinstalled. Dull blades can sometimes be sharpened, while damaged blades should be replaced. See the section below for more details about when a miter saw blade needs replacement.
2. Disconnect the power. Unplug your miter saw before performing any maintenance, including removing the blade.
3. Check the manual. If you still have the user manual for your miter saw, consult it for model-specific blade-changing instructions. Alternatively, you can search for the manual online.
4. Remove the blade guard. A properly installed blade guard is a critical part of preventing miter saw accidents. Blade guards usually attach via two screws, one in the front and one in the back. Remove the front screw and make sure to place it in a safe location. Flip the blade guard back, exposing the blade.
5. Lock the blade. The blade is mounted on a spindle, allowing it to rotate. Most miter saws have a button you can press to stop the spindle from turning. Without the spindle immobilized, you will not be able to remove the blade. If there is no spindle lock on your machine, find an appropriately-sized wrench and use it to hold the spindle in place.
6. Loosen the nut. Locate the bolt that is holding your miter saw blade in place. With the spindle locked in place, use the appropriate tool to loosen the nut. Most miter saws require a wrench or Allen key. The bolts of miter saws are usually reverse-threaded, meaning the nut will only loosen when you turn it to the right.
7. Remove the blade. Take the nut and the washer off the bolt and put them in a safe place. Put on thick gloves, then grasp the blade. Ease the blade off the bolt.
8. Install the new blade. Grasp the blade with both hands. Slide it onto the bolt. Replace the washer and the nut, and use the appropriate tool to tighten the nut, securing the blade.
9. Restore the blade guard. Flip the blade guard back down and reinsert the screw holding it in place.

Related: Learn how to unlock your miter saw to perform maintenance.

When to Change a Miter Saw Blade

There are three reasons you might want to change your miter saw blade.

• To change the speed and coarseness of your cut.
• To correct issues with the blade, such as improper installation, damage, dullness, or build-up.
• To prepare for cutting a different material, such as switching from cutting metal to cutting wood.

Changing a blade can extend the life of even beginner miter saws. However, if you continue using a damaged blade, you can cause damage to the miter saw itself.

Cut Speed and Coarseness

The blade included with the purchase of your miter saw is most likely a general duty blade, with 40 to 60 teeth per inch. This kind of blade will quickly saw through rough stock, trimming it to size.

When you want a finer, cleaner cut, it is necessary to change the blade. Choose a crosscutting blade with 80 to 100 teeth per inch. The cutting speed will be reduced, but the results are worth it.

Blade Issues

The blade is the most important component of a miter saw and has the most interaction with the material you are cutting. An issue with the blade will affect every cut you make and may require changing the blade.

Damaged Blade

Using a miter saw blade on the incorrect material can cause damage to the tool, such as chipped teeth. While a miter saw can still operate fairly well with a few chipped teeth, any more than that leads to material damage.

Dull Blade

Perhaps the most obvious reason to change your miter saw blade is that the old blade has become dull.

You should suspect a dull blade whenever you are not getting clean cuts from your miter saw.

Tearing, chipping, and burning on the wood can all point to a dull blade. If the cutting speed feels sluggish, you’re getting resistance, or your miter saw starts to smoke, stop cutting and check the sharpness of your saw blade.

Dirty Blade

As you make cuts with your miter saw, debris from the material you are cutting will transfer onto the blade. A dirty blade won’t make clean cuts. For your safety, and for the efficacy of the cleaning process, you should always remove the blade from your miter saw for cleaning.

Blade Installed Backwards

When installing a new blade for the first time, it’s easy to get confused or distracted. Without realizing it, it is more than possible to install a new blade facing the wrong direction.

The saw will still make cuts if the blade is configured inappropriately, so this can be a tough issue for newcomers to spot. To check if your blade is installed correctly, take a look at the teeth. As the saw teeth meet the material, the tip of the tooth should be pointing downwards.

If it’s not, you’ll need to remove the blade and reinstall it in the correct direction.

Changing Materials

One reason you might need to change your miter saw blade is when you’re switching between materials.

Miter saws are most often used to make angled cuts on milled lumber, and most of the time you’ll probably have a wood-cutting blade installed.

However, with an appropriate blade installed, top miter saws can also be used to cut non-ferrous metal. Metal blades generally have more teeth per inch than blades designed to cut wood. The shape of the teeth or their orientation may also be different than wood-cutting blades.

Yet another material that miter saws can cut through is masonry, including bricks and pavers. Masonry blades are used for cutting bricks and pavers, and natural stone.

What Blade Is Best for Miter Saw?

The best blade for your miter saw depends on what result you are trying to achieve. Two important qualities to evaluate are the number of teeth per inch and the material of the blade.

Teeth Per Inch

The number of teeth per inch (TPI) on the exterior of your saw blade gives you information about how it will perform.

Blades with larger teeth have fewer teeth per inch. Blades with fewer teeth take a larger ‘bite’ out of the material. Use blades with low TPI for aggressive cutting that doesn’t need to look pretty.

Blades with smaller teeth have more teeth per inch. Smaller teeth cut more gently and more slowly, leaving a smooth, crisp cut behind. A saw with high TPI is best suited for fine woodworking.

Blade Material

The composition of your blade determines what materials it is able to cut.

High Carbon Steel Blade

A high carbon steel blade is used for general-purpose wood cutting. The blade that came with your miter saw is likely high carbon steel.

Combination Blade

Multi-material blades are best for cutting composite materials, such as plywood, particleboard, or melamine.

Diamond-Tipped Blade

Diamond-tipped blades generally have rectangular teeth. They can grind through non-ferrous metals (such as aluminum) as well as masonry.

Carbide-Tipped Blade

Blades with teeth tipped in carbide are very hard, resisting wear and tear while easily slicing through wood and certain metals.

Aluminum Oxide Blade

An aluminum oxide blade is another option when you want to cut soft, non-ferrous metal.

Conclusion

Miter saw blades must occasionally be changed, whether due to issues with the blade or a change in cutting requirements. Changing the blade is relatively simple and requires only a few wrenches. For best results when using a miter saw, make sure the correct blade is installed for the material and purpose of your cut.