How to Change a Miter Saw Blade

A 10 inch miter saw with the blade removed.

Knowing how to change a miter saw blade is an important skill for any woodworker. Along with replacing dull blades, it’s useful to switch between blade types for different jobs.

Luckily this is a really simple job that only takes a few steps:

  1. Turn off the saw and disconnect power
  2. Remove the blade guard
  3. Remove the spindle cover
  4. Remove the spindle bolt and blade flange
  5. Take out the old blade
  6. Fit the new blade
  7. Check calibration of your saw.

I’ll cover these steps in much more detail below so you’ll know exactly what to do. First though I’ll cover the reasons why you should change a miter saw blade and how to check when the blade needs changing.

I’ll also look at how to choose the right miter saw blade, whether this is replacing the existing one or choosing a new saw blade for a specific job. Hopefully by the end you’ll be an expert in changing miter saw blades!

Why Should You Change a Miter Saw Blade?

It probably doesn’t need pointing out, but like any other type of saw, a miter saw blade will get dull over time. This is the most obvious reason for needing to change it, but there are others. These include:

  • Working with different materials.
  • Needing a cleaner cut.

Working with a dull blade can lead to many problems. It can damage the material you’re cutting or leave burn marks from the increased friction. Considering miter saws should make cutting easy, these issues are the last thing you want.

Miter Saw Blades for Different Materials

Another reason for changing blades is when you’re working with different materials. For example, the best saw blade for cutting framing work won’t be suitable for crown molding.

Choosing the right kind for your project goes beyond the number of teeth. It also involves the blade material, tooth configuration, gullet, and much more.

This point is covered in more detail later in the article.

Miter Saw Blades for a Cleaner Cut

The number of teeth is the biggest factor that affects how clean a cut will be. A blade with a higher tooth count will make a finer cut, whereas one with a lower tooth count will make a rougher cut.

Some projects don’t need precision. For example, if you’re just cutting down lumber to a workable size, a 24-tooth would be fine. But if you’re building furniture, you’d want to look at an 80 to 100-teeth instead.

The Importance of a Sharp Miter Saw Blade

You might have already realized the importance of a sharp blade, but it’s worth repeating. A sharp blade means cleaner and faster cuts, and less change of damaging your material.

Whether you’re a hobbyist or a professional woodworker, speed and precision are always important. Also, why would you want to risk damaging your potentially expensive materials?

How to Check When to Replace the Miter Saw Blade

Of course, before you start trying to replace the blade, it’s worth checking if this is necessary. There are a few things to check:

  • The cut looks rougher than it should.
  • Burn marks on the wood.
  • Cutting much slower than expected.
  • Noticeable signs of wear on the teeth.

The best advice I can give for knowing when to replace the blade is to familiarize yourself with the tool before using it. Researching differnt types and cutting jobs will provide a good base knowledge, which you can then use when needed.

Before going any further, it’s worth checking if it is just dirty. When cutting wood, dust and resin can build up on the blade and clog the teeth. This can be a particular issue if you cut a lot of sappy softwood. The buildup of dust and resin leads to an increase in friction while cutting and can burn the wood, giving a similar experience to a dull blade.

Check it over, and if it looks dusty then give it a clean. This might make enough difference.

Checking a Dull Miter Saw Blade

Knowing the warning signs of a dull blade helps you to spot them in the early stages. This means less potential damage and less wasted materials.

If it gets to the point that your blade is dull then you should be able to check this fairly easily. Common signs include slow cuts and burns to the wood.

If you’ve been using the saw enough for the blade to go dull, you’ll hopefully notice that it’s cutting slower than before. Look out for changes in the quality of cut and burn marks too. If cuts look rougher on the same type of material then it’s time for a change.

The Right Blade for the Job

As mentioned, different jobs need different types of blades. Using the wrong one can lead to rough cuts, cuts taking too long, and damage to the material.

If you’re looking to make quick rough cuts when doing framing work for example you’re going to want to use a one with fewer, larger teeth. For finishing work or cabinetry you’ll want something with more, smaller teeth. 

It’s worth checking what’s the best type before starting the job, as it’s too late once you’ve started. Also, using the wrong one can cause damage to the blade itself, which is best avoided.

How to Choose The Right Miter Saw Blade

There are a few factors you need to consider when choosing the right one for your project. The most important are blade material and tooth count, but make sure you also consider the following:

Arbor Size

A saw blade’s arbor is basically another name for the spindle mechanism that rotates. The arbor hole, then, is the hole in the middle of the blade where the arbor goes.

The arbor hole changes in size depending on the blade’s diameter. 10” blades tend to have an arbor hole size of 5/8” and 12” blades tend to have arbor holes of 1”. 

Miter saws come in 8”, 10” and 12” models. Make sure you choose the right arbor size for your model when choosing a new blade. The arbor size will be consistent across all blade types for the size you buy.

If you’re wondering, ‘Should I get a 10” or 12” miter saw?” then this does depend on a few factors.

The bottom line is that a 10” miter saw can spin faster because its radius is smaller. This means smoother, more precise cuts. However, a 12” miter saw can cut larger pieces of wood because it has a larger radius. The best size of miter saw depends on what materials you’ll be cutting most often.

Tooth Count

The tooth count on a blade affects the quality of cut you’ll get. A general rule is that a higher tooth count will result in a cleaner cut. But a blade with a lower tooth count will give a rougher cut.

As it’s the teeth that ultimately do the cutting, it’s important to get this right. For a standard all-purpose blade, 60 to 80 will be fine.

If you want a smoother cut, or are working with softer materials, a tooth count of 100 will be better. For materials such as hardwood, or for making quick rough cuts, you can go as low as 24 teeth.

You can also think about whether you’re making crosscuts or rip cuts. Rip cuts are for literally ripping wood, meaning they don’t need to be precise or pretty. For this you’ll want a lower tooth count.

If you want to cut across the wood’s grain, you’ll want a crosscut blade. These have a higher tooth count, usually above 60, and won’t tear the wood. Also, for cutting through metal, you’ll want a blade with a tooth count over 80.

Tooth Shape

Like tooth count, tooth shape affects the speed and quality of cut. Also, some tooth shapes are better for certain materials, so it depends on what you want to cut. The most common types are:

Alternate Top Bevel – The saw blade’s teeth are beveled (angled) in alternating directions. This means each tooth has a right and left bevel. Alternate top bevel teeth are most common on crosscutting blades and are best for things like softwood and plywood.

 Flat Top – Flat top teeth are exactly what they sound like: flat on top. These are most common on rip blades because when cutting with the wood grain there is less chance of it splintering.

 Triple Chip Grind – These blades have alternating teeth. One is flat and the next is a trapeze shape. They’re ideal for cutting hard materials like plastic and laminates, but can also cut metal.

 While there are other tooth shapes, these are the ones you’ll come across most often. As you can see, tooth shape depends on the material you’ll be cutting, so pay attention to this when choosing the right miter saw blade.

Kerf

A blade’s kerf refers to the width of the cut the blade will make in the material. By extension it also refers to the width of the blade itself, which is measured on the width of cut it makes.

Saw blades come in “full kerf” and “thin-kerf”. A full-kerf cuts at a width of 1/8” and is designed for saws with a motor greater than 3HP.

A thin-kerf cuts at a width of less than 1/8” and is generally designed for cordless miter saws. Most miter saw blades you’ll find will be full-kerf varieties.

It’s important to get the right kerf width for your model because if you mount a thicker blade on a less powerful saw then it won’t spin at the right speed. Using a full kerf on a cordless saw will mean the battery life is massively reduced.

That said, you can use a thin-kerf blade on a miter saw with little issue. The most obvious benefit is that it saves material. While less than 1/8” might not sound much, if you’re cutting hardwood that costs $80 per panel, you’ll want to save as much as possible.

Blade Material

Blade material is one of the key factors to consider when choosing the right one. Harder materials are more resilient, and so will stay sharp longer. This is important when cutting harder materials.

The main materials you’ll find are:

Carbon steel – This is the most common blade material. They’re inexpensive and readily available, making them the go-to for many saw users. Carbon steel blades are best for cutting soft materials like natural softwood and plastic.

High speed steel – HSS blades are basically tougher versions of carbon steel blades. They last longer and can be used at higher speeds without getting dull. But they are more expensive. Typically they’re used to cut through materials like hardwood. While you can use them on softer materials, their cost doesn’t really justify this purpose.

Carbide tipped – Carbide tipped blades tend to be the most expensive type of blade, but are arguably the best. The blade’s body is still made of steel, but have carbide-tipped teeth.

They’re much harder than steel blades and so can cut through materials like metal. You can use them on softer materials too, and they’ll make light work of them. Also, you don’t need to replace them as often.

Choosing the right material depends on what you’re cutting. Steel blades will probably be your go-to, but if you want the best performance-to-value ratio, carbide tipped blades are the way forward.

How to Change a Miter Saw Blade

Now that we know when to change your blade and how to choose the right one, it’s time to cover the steps of replacing it. 

1. Turn off the saw and disconnect power 

The first obvious step is to turn the saw off and disconnect the power. This is good practice before working on any power tools and ensures the tool can’t be turned on by accident. Test the power by trying to turn it on and off to double check.

2. Remove the blade guard

To remove the blade guard, you start by rotating the guard up so the blade is completely exposed. Most models will have a lock that holds the guard in this position.

Some models will require a screw to be removed in order to rotate the blade guard fully in order to get full access to the blade. This is normally done with either an allen key or a screwdriver but will vary from model to model. 

Once the screw is removed the guard should rotate further and give full access to the blade.

 3. Remove the spindle cover

 On some models of miter saw the spindle cover will be part of the blade guard assembly and will be removed following the previous step. Some models won’t even have a spindle cover so this step can be skipped. 

For saws with an independent spindle cover this can be removed by simply removing the screw holding it in place. In most cases it’s held on with a single screw, however on some models there might be a second screw further back. 

4. Remove the spindle bolt and blade flange

Now the blade is fully exposed, it’s time to remove it. In order to do this you’ll need to remove the spindle bolt, outer washer and the blade flange. 

The spindle bolt will normally be either an allen key or a hex bolt. You might have a blade removal wrench supplied with your saw. if not you’ll need to find a suitable sized allen key or wrench. 

Before you try to loosen the spindle bolt you need to find the spindle lock to prevent the blade from rotating. This will be either a button or a lever depending on the model. Press the spindle lock and rotate the blade until the pin locks into the detent and the blade stops spinning.

If your saw doesn’t have a spindle lock you can use a piece of scrap wood instead. Simply place the piece of wood against the fence under the blade. When you’re ready to remove the spindle bolt, lower the blade so the teeth touch the piece of wood. When you start to turn the spindle bolt the teeth should bite into the piece of wood and prevent the blade from spinning.

When it comes to removing the spindle bolt be aware that it will likely be a left-hand, or reverse thread. This basically means that you’ll need to turn it clockwise to loosen it rather than counterclockwise like normal bolts. 

Once the spindle bolt is removed the blade flange can simply be slid off of the spindle shaft. 

5. Take out the old blade

Providing you’ve followed all of the previous steps this part should be really easy, simply slide the blade off the spindle shaft to remove it. Take care while you’re doing this as even a dull blade might have areas of the teeth that are still sharp. Wearing a pair of gloves while doing this will eliminate any risk of cuts. 

6. Fit the new blade

This step is just the previous one in reverse. Use this time to wipe down the inner and outer washer. 

Fit the new blade in the right direction using the arrows on the side as a guide. Tighten everything properly before replacing the guard.

7. Check calibration of your saw

Although this might not be required, it’s always good to take this opportunity to check the calibration of your saw. In short, check the blade and the fence are properly aligned, and that all parts are at the right angle. You should also try a test cut for reference. For more information, check this guide on tuning a miter saw blade.

That’s really all there is to it. However, consider the following safety tips:

  • Wear gloves when changing the blade as the teeth can easily cut you.
  • Remember to unlock the spindle lock before using.
  • The bolt holding the blade in place must be turned clockwise to loosen.

Conclusion

Learning how to change a miter saw blade is vital for getting the most out of this versatile machine. As you can see, it’s a fairly easy job, but it’s worth knowing the full process before starting.

If you’re switching between materials, then knowing which type is best will help you to get the most out of your project. Hopefully the saw blade selection guide above has answered any questions you might have about this.

Do you have any helpful tips for changing a miter saw blade that’ll benefit others? If so, leave them in the comments below!

Leave a Comment

Your email address will not be published. Required fields are marked *