Knowing how to change a miter saw blade is one of those necessary tasks that, to the uninitiated, can turn into a knuckle-busting endeavor. The blade guards are positioned so that it seems impossible to get to the bolt holding the blade to the saw.
Luckily, most modern saws are designed in a way where you should have clear access to the blade bolt with the removal or loosening of a screw or two.

How to Change a Miter Saw Blade
Each saw brand will have its intricacies, but the process is generally the same across the board. It’s always a good idea to look at the manual for your saw before getting started to get an idea of the exact steps for changing the blade on your miter saw.
Suppose you’re like me and can never find the manual; virtually every power tool manual is available online now. Sites like Vintage Machinery are an excellent resource for finding manuals for older tools.
Unplug Your Saw!
Before you start any tool maintenance or repair, always unplug it first! This is especially true for tools with a trigger pull like miter saws. It is extremely easy to accidentally pull the trigger while working on the saw versus paddle-type switches found on table saws.
Loosen the Blade Guard Bolt

On most miter saws, the blade guard is attached to a piece of metal that pivots on one end and is attached to the saw with a bolt on the other end. Loosen that bolt, in my case, with a 1/2″ socket or wrench.
If you need to disconnect the blade guard from the control arm, this can be done by removing the screw here.

Do not remove the nut in the center of the blade guard, as this holds the spring mechanism together and can be a real pain to reassemble!
Swing the Blade Guard Back

Now you can swing the blade guard back far enough to access the blade bolt. I can swing the guard back on my saw and then shift it slightly so it rests on one of the exposed bolts and won’t swing shut.
Lock the Blade

On the other side of the blade, you’ll find a blade lock. This prevents the blade from spinning while removing the blade bolt. The blade lock on my delta miter saw is a pin that you push down to engage. Other saws can have paddles or buttons that do the same thing.
To engage the lock, depress the pin and spin the blade until it locks into place.
Note that you have to manually hold down this lock while removing the blade bolt.
Remove the Blade Bolt

Once again, use your 1/2″ wrench or socket to loosen the blade bolt. This bolt is left threaded, so it loosens in the opposite direction of most bolts. Keep the blade lock depressed to prevent the blade from spinning during this process.
If your saw does not have a blade lock, you can put a piece of wood on the saw and lower the blade, so the teeth are against the wood. This will prevent it from spinning while loosening the bolt.
Remove the Blade

Remove the bolt and arbor nut and remove the blade.
Replace the Miter Saw Blade
Put your new blade back on the miter saw and replace the arbor nut and blade bolt. Note that your blade should fit snuggly on the arbor. If it wiggles too much, then you may have a blade with the incorrect arbor size for your saw.
Reinserting the blade is usually a pretty tight fit so go slow so you don’t damage a blade tooth.
Note the direction of the arrows on the blade and the tooth orientation. The arrows printed on the blade should be facing down, and the teeth on the blade should be facing down as well.
Early in my woodworking career, I put a miter saw blade on backward, and it took me a minute to figure out why the saw was cutting so slow!

Tighten the Blade and Guard Bolts
Once the blade is back on, tighten the blade bolt. Once again, note that this bolt is threaded backward versus standard bolts, so you’ll be turning it away from you vs. towards you to tighten it.
Pull the guard back down and tighten the bolt holding it in place.
Test the saw by raising on lowering the blade and guard to ensure adequate clearance and everything is moving as it should.
On most standard-sized miter saws in North America, the arbor size is 5/8″. The arbor size refers to the size of the hole in the center of the blade, which fits around the arbor on the miter saw.
Miter saws come in blade sizes from 8-inches all the way up to 15 and even 20 inches! The most common blade size on a miter saw is either 10 or 12 inches. The size of the blade on the miter saw dictates how deep of a cut it can make, so if you’re frequently working with extra thick wood, then look for a larger-sized blade miter saw.
The blade bolt on the miter saw is reverse, or left hand, threaded. This means that instead of righty-tighty, lefty-loosey, it is reversed. So turn the bolt towards you to loosen it and away from you to tighten it.
Yes! Most blades are not sold as a miter saw specific as they can work on table saws, miter saws, circular saws, or radial arm saws. Check the blade size, arbor size, and cut quality when choosing a saw.
Yes! While some miter saw blade brands are better than others, you can use any brand that offers the best combination of quality and price to meet your needs.
Miter Saw Blade Size

Derek grew up woodworking in his father’s shop and has since gone on to start up a successful woodworking business on Etsy. In his spare time, you can find him mountain biking, skiing, or writing.