I have looked at a lot of miter saws and found that the vast majority of them either have a 10-inch or a 12-inch blade. I wanted to take a look at the differences between them and share what I found out, so you can decide which will be of more use to you for your woodworking projects. Apart from the obvious difference in size, each one also has different capacities and different uses for which they are ideal.
One significant advantage 10-inch miter saws have over 12-inch models is that they typically spin faster. 12-inch models tend to spin slower because the blades have a larger radius. Say you have a 10-inch saw that spins at 5000 rpm like the DEWALT DW713. It will run at about the same speed as a 12-inch saw that spins at 4000 rpm. More speed makes smoother cuts, so you will want to consider this factor carefully when deciding which saw you really want.
10-inch blades are much easier to come by, and your local hardware store will mostly likely have a large collection of 10-inch blades to choose from. This kind of availability can be a great advantage if you need to replace your blade in a hurry and don’t have time to shop around. 10-inch blades are also more affordable at the outset, and the cost to sharpen a 10-inch blade is lower than what you’ll pay for having a 12-inch blade sharpened. Additionally, to get the same quality cuts that you will get from a 10-inch blade, a 12-inch blade will need more teeth, which will make them more expensive. So if price is a big factor for you, a miter saw that uses a 10-inch blade will be a really good choice.
The drawback to a 10-inch blade is that they have a limited cutting capacity. They can usually be used to cut up to 6 inches of material. For most woodworking projects, a 10-inch will work just fine, though, and as long as you are not doing large projects like decking, this is probably not likely be an issue.
Although it isn’t always the case, I found that most 12-inch miter saws have more power than 10-inch models. You can verify this by checking the number of amps a miter saw’s motor has. The majority of 12-inch models have 15-amp motors and this gives them a lot of power for cutting larger, thicker pieces of material. The ability to cut larger pieces makes 12-inch miter saws more versatile, but if you don’t do large cutting jobs, you may not have much need for this type of saw.
However, there are many 12-inch miter saws that will allow you mount 10-inch blades on them. This means you can have the best of both worlds, and I rather like that idea. Another advantage to having a 12-inch miter saw is that they normally have a higher tooth speed, which is more likely to give you smoother cuts. This can be especially helpful if you are doing fine woodwork. 12-inch miter saws are also normally more durable and, therefore, more likely to last longer.
With the exception of the Bosch GCM12SD and a few other high quality miter saws that can cut up to 16 inches of material, if you have very large pieces like 2 x 12s, the average 12-inch miter saw will not be able to go through them with a single cut. It will normally take at least two cuts to get through. I don’t really consider this to be a limitation, though, as 10-inch models would not be able to even come close to this capacity. 12-inch models tend to be more powerful, and that means they use more electricity, which might not good news for your electricity bill if you plan to use your saw often.
12-inch miter saws are more expensive than their 10-inch counterparts. The replacement blades can also be quite pricey. Unless you’re sure you will be able to take full advantage of all that a 12-inch has to offer, it may not be worth it for you to buy one. I have seen many a miter saw end up in early retirement after only one or two uses. If you know you won’t be using your miter saw much, it is not necessary to spend a lot of money on one. Unless, of course, you like to decorate your workshop with expensive, shiny tools.
The Bottom Line
Unless you really have a need for a specific size miter saw, if you have other power tools that use the same kind of blades, you may want to consider sticking to that blade size. I have a 10-inch table saw, and unless some kind of really great project comes along that I absolutely must have a larger blade for, I’m going to stick with a 10-inch miter saw. It’s nice to be able to share blades between them and doing so saves a lot of money. You’ll need to make a decision based on your own needs, but I hope the information I’ve provided here helps you do so.