Circular Saw Blades

What types of circular saw blades should I buy? Which blade for metal and which one for plywood?

Let me help you with the right answer:

A circular saw is an incredibly useful tool and you will find one in almost every workshop out there. However, like many power tools, a circular saw is only as good as the parts that go into it. In this case, I am referring to the blades that you use on your circular saw.

Choosing the right blade for your circular saw is crucial if you want your circular saw to operate at peak efficiency. But, what is the best blade for each job? That is where I come in. I will give you all the information that you need to make an informed purchase when it comes to circular saw blades. I will tell you about the different kinds of circular saw blades and what kind of blade is best for each job.

Types of circular saw blades

Different types of circular blades are available according to their intended purpose. Standard blades are used in carpentry work, while abrasive blades are for metal cutting and diamond blades for masonry work.

You will also find blades with different thicknesses and number of teeth which I explain in detail later. For now, understand that a fine blade will have a large number of small-sized teeth. Conversely, a rough blade will have less number of larger sized teeth that enable it to cut through the material much faster.

Blade Selection Guide

In case you are in a hurry, here is a quick selection table for reference.

Standard circular saw blades

As you have probably figured out from the name, standard blades are the blades that you will use for most jobs. They are great at cutting wood and come in several sub-varieties for different kinds of woodcutting jobs. Some of the different kinds of standard blades that you will see include:

• Rip-cut blades: These kinds of blades have a low number of teeth, some have as low as 16 teeth, while others have closer to 40 teeth. The lower number of teeth allows for aggressive cutting and enables you to make larger cuts.
• Framing Blades: Closely related to rip-cut blades are things called “framing blades.” These blades also have a very low number of teeth, usually 24 and are intended to make cuts aggressively and quickly. Both rip-cut blades and framing blades are ideal for situations where speed and volume are more important than precision.
• Crosscut blades. These kinds of blades have a higher number of teeth. Very often you will see these kinds of blades having teeth numbering in the 60 to 80 range. The higher number of teeth allows you to make more accurate and cleaner cuts through wood.
• Plywood blades: These kinds of blades have the highest number of teeth that you will find on a commercial saw blade. The blades often have over 100 teeth. The purpose of these blades is to make the absolute finest cut possible with minimal damage or ripping is done to the wood.

Abrasive blades

Abrasive blades or discs are a unique kind of saw blade. They don’t “cut” like traditional circular saw blades do. Instead, abrasive discs work in a similar fashion to grinders. Abrasive discs tend to be out of different abrasive materials as well. Silicon carbide and aluminum oxides are two of the most widely used material to produce abrasive circular saw blades.

Abrasive discs are useful for cutting through hard materials like steel. You can also use them for your masonry jobs although a diamond blade is a much-preferred choice.

Diamond Blades

These are blades made out of steel with synthetic diamonds speckled throughout them. The diamond circular saw blade is mainly used for masonry works. These blades can cut through very hard materials like concrete, bricks, stones, and tiles.

1. Continuous rim blades

These blades have no teeth, which is the main thing that differentiates them from standard circular saw blades. These kinds of blades are specifically designed to cut through materials like tile. Therefore, they are not particularly suited to cutting through the wood; that job is better left to standard circular saw blades.

2. Turbo rim blades

Conceptually, turbo rim blades are very similar in appearance to continuous rim blades in that both have no teeth. However, turbo rim blades are serrated, which gives them a lot more raw cutting power. Because of this, turbo rim blades are the kind of saw blades that you want to use when you need to cut through really tough materials like say concrete or brick.

3. Segmented blades

Segmented blades are rimmed with diamond edges. However, each edge is separated by a small gullet, which sets them apart from turbo rim blades and continuous rim blades. Because of these gullets, segmented blades are able to deliver a lot of cutting power, but with less accuracy and surface finish. If you need to quickly cut through tough materials like hardwood, concrete, or brick, and you don’t care about resulting rough cut edges, then a segmented blade is the best option.

Wet Vs Dry Cutting

Some of the circular saw diamond blades are for wet cutting while others can only do the dry cutting. Which one to choose, depends on your circular saw and the type of application.

Dry Cutting: If you have a small handheld circular saw or a cordless one, then dry cutting blades may be your only option. Dry cutting is recommended for intermittent cutting. If you are doing home improvement jobs where you are working within limited space, dry cutting blade is a great choice.

Wet Cutting Blades: In case of wet cutting water is used to absorb the heat from the blade as well as to wash away the debris. Wet cutting is the preferred method for masonry work especially for tile cutting since it works faster, cleaner. Another advantage of wet cutting is that it provides longer tool life.

However not all electric circular saw support wet cutting since there is the risk of electric shock.

Circular Saw Basics – Hook angle and kerf

There are two other very important concepts to consider when buying a circular saw blade. First off is the idea of a hook angle. Saw blades come in various hook angles; ranging from a high of around 20 degrees to a low of about -5 degrees. The higher a blades’ hook angle, the more effective it is going to be at ripping through softer materials. So, if you want to cut through a lot of softer material, very quickly (like softwood) then go for blades with a higher hook angle. On the other hand, blades with a lower hook angle deliver more precise cuts, but they cut at a much slower rate.

Another important concept is the idea of a blade’s kerf number. This is really just a fancy way of referring to how thick a blade is. Blades that are thicker (aka ones that have a higher kerf number) are better for cutting through tough materials and they tend to be more durable. Blades that are thinner (aka ones with a low kerf number) are better for making smaller, but more accurate cuts; however, they are less durable and not as good for cutting through larger amounts of material.

Blade size

Circular saw blades come in a variety of sizes. This is important to keep in mind since certain size blades only work with certain kinds of saws. For example, a smaller sized blade (such as a 7-inch blade) is only going to work with smaller circular saws, such as handled models. Likewise, bigger blades (such as 12-inch blades) will work with bigger models, like table saws. Needless to say that, the smaller diameter blades cut shallower than larger blades.

So before you buy the blade, check your saw and find out the arbor size and the maximum diameter it can accept.

Best Circular Saw blades for different material

In this section, I will quickly go over what the best circular saw blade type is for cutting each kind of material.

Woodworking Blade

For cutting wood, I say the best option is to go with a standard circular saw blade. For something as simple as cutting wood, there is no reason to go for a more expensive saw blade. Depending on the kind of woodworking, you will want to be careful about how many teeth the blade has. If you are just cutting through large amounts of lumber, then I recommend going for a blade with a lower number of teeth, it will save you time. If you need precision, make sure you get a blade with a high number of teeth, the more teeth, the more precise your cuts will be.

Blade for Plywood

Because of how thin plywood is, you will want to go for a very precise standard saw blade. A lot of circular saws come with a blade that they recommend using for thin materials like plywood. My advice is to ditch that and buy a specialty blade. The blades manufacturers include with their saws are almost always the wrong kind and they will decimate plywood.

By investing in a low kerf, high tooth count blade, you will ensure that you can accurately cut through plywood without damaging the edges.
You can use the plywood cutting blade to cut laminate as well.

Circular Saw Blade for Metal

Non-Ferrous Material: Carbide tipped non-ferrous blades are ideal for cutting aluminum and other softer metals like lead, brass, and bronze. If you are going for this type of blade, I suggest you get a blade with an anti-kickback design.

Ferrous Metal: If you have a job or project that requires you to take your circular saw to steel, then I wholeheartedly recommend investing in an abrasive blade. Those are the absolute best option for cutting steel and harder materials.

If you use the wrong kind of saw blade, you risk damaging your circular saw.

Tip Not all circular saws accept abrasive discs. Make sure that your circular saw model supports the use of abrasive blades.
DO NOT use abrasive blades on a table saw to cut metal. It is a dangerous practice.

Masonry Concrete Cutting Blades

For cutting concrete, a diamond blade such as a segmented or turbo rim blade is essential. Much like with woodworking, the specifics depend on what you need the concrete to look like afterward.

If you just need aggressive, speedy cutting, then go for a segmented blade. If you want a bit more precision, a turbo rim blade is the best option for cutting through concrete with some precision.

Abrasive discs can also be used for light-duty masonry work. One advantage of the abrasive blade is that they are much cheaper when compared to diamond blades. However abrasive disc wears out pretty fast and requires a lot more time to accomplish your task.
The most efficient circular saw blade for concrete and tiles cutting is a diamond blade designed for wet cutting.

Circular Saw Blades Infographic

See the infographic below that represents the best blade for each type of work.

Conclusion

So many people invest so much thought into what kind of circular saw they are going to buy for a job that they forget to think about what sort of blade they are going to use. By using this guide, you can make an informed purchase about what circular saw blades to use for each job; which will save you time and money down the road.

Circular Saw Blade FAQ

Can I use the circular saw blade on a table saw?

Yes. However, using a circular saw blade on a bench saw has its pros and cons.
Advantages
Thin Kerf: Since the circular saw blades are thin, they require less power to cut through. The thin kerf also produces less sawdust and result in more usable wood.

Inexpensive: The circular saw blades are cheap compared to table saw blades.

Disadvantages
Depth of cut: Circular saw blades generally available from diameter 4-1/2 inches to 7-1/4 inches. If you use this smaller diameter blade on your 12 inches table saw, you will end up with a shallow depth of cut.

Circular Saw blade direction, which way?

A Circular saw is designed to cut upwards. That means unlike the table saw, the direction of blade rotation is anti-clockwise. Nearly all the manufacturers have the direction marked on the blade guard. All you need to do is to make sure that the directions of arrows on the blade and on the saw body are in the same way.
Look at the image below for explanation.

Installing the blade in the wrong direction will result in damaged cutting edges and excessive heat.

How to change circular saw blade?

Replacing the blade on a circular saw is pretty simple. Here are the steps:

1. Unplug your circular saw. If it is battery powered, remove the batteries.
2. Find the blade lock. Nearly all the circular saws have an arbor lock switch.
3. Push the blade lock and slowly rotate the blade with your other hand until the blade lock mechanism engages.
4. In some cases, you may have to push the lower guard back.
5. Use the correct wrench to remove the arbor nut (blade stud) while holding the blade lock button.
6. This is a normal right-hand thread nut. So you have to loosen the nut by rotating in the anti-clockwise direction, which is the same direction the blade rotates.
7. Remove the washer and lift the blade slightly up to remove it from the arbor.
8. Blow air and clean the inside of upper and lower guard.
9. Slip in the new blade. Make sure that the blade teeth are in the right direction.
10. Place the washer and lock the nut/blade while the blade lock is engaged.

Here is a video that explains the process.

Tip: Before you put the blade stud back, put a drop of oil on the threads to make sure that they don’t get rusted and you can easily unlock the nut next time.

Can I sharpen the circular saw blade?

Yes.
Ideally, you should do it on a tool and cutter grinder or use a special blade sharpener. How severely the cutting edges are just dull and not severely damaged, you can sharpen the blade by yourself.
You can use file and oil stone to sharpen the standard wood cutting blades that are made out of steel. Here is a video that explains the process.

You could also mount the blade in reverse direction on a table saw and move the blade up until it touches an oil stone that is fixed on the table. Here is an article on sharpening the blade with oil stone.
Carbide tipped blades: If you have a diamond wheel you can fix that on your table saw and touch the carbide tips to make them sharp. However, I do not recommend this to novice users since it can be dangerous and may cause injury. Send your carbide blades to a professional resharpening service provider to get the best result.