We’ve covered table saw blade height, miter saw usage, table saw safety, and circular saw blade maintenance, but with such a wide variety of circular saw blades available, how do you choose the right one for your work? Even if you are a pro at handling a miter saw, the options can be overwhelming. Different blades feature various tooth configurations, such as multiple or few teeth, continuous rims without teeth, wide or thin blades, as well as negative or positive rake blades. Some even claim to be all-purpose, which only adds to the confusion. Fear not! We have simplified things for you with this helpful guide to selecting the ideal circular saw blade.
Simplifying the Decision-making Process
The functionality of a circular saw blade depends on several factors, including:
Number of Teeth
The number of teeth on a blade affects the speed and the quality of the cut. Blades with more teeth provide smoother and finer cuts, while those with fewer teeth offer rougher cuts. Blades with fewer teeth cut faster and are less expensive. For most construction tasks, a 24-tooth general-purpose blade will suffice. This aggressive blade allows for speedy and precise ripping and cross-cutting. However, it won’t give you a near-finished edge. Keep in mind that the number and size of the teeth per linear inch of the blade matter more than the total number of teeth. When shopping, consider choosing a finer thin-cut finishing blade for cutting hardwood or achieving cleaner edges.
The spaces between the teeth, known as gullets, determine how much waste material the blade can clear as it rotates. The gullet size is directly related to the number of teeth.
The rake angle refers to the angle at which the teeth touch the cutting surface. Blades with a positive rake angle aggressively remove material, resulting in faster but rougher cuts. A positive rake angle is ideal for down-cut or self-feed applications. However, it can be dangerous when cutting metal. On the other hand, blades with a negative rake angle cut less aggressively, resulting in smoother cuts with less material removal. Neutral rake angles are also available.
The bevel angle is the angle at which the teeth rotate across or perpendicular to the blade. Larger bevel angles produce cleaner and smoother cuts. Blades with high bevel angles are suitable for cutting materials with thin veneers, such as melamine, that can chip easily. Bevels can be flat, alternating, high alternating, or have other configurations.
The kerf refers to the width of the tooth at its widest point and determines the width of the cut. Thinner kerfs create less resistance while cutting, making them more suitable for low-powered saws. However, thinner blades can cause vibration or wobbling, resulting in cuts that show blade motion. New blade technology with vibration-damping designs offers improvements in the thin-kerf segment.
Choosing the Right Blade
Now that we have covered the key factors, selecting the right circular saw blade becomes easier. Start by determining the type of cut you need – across the grain or lengthwise. Consider whether you want a rough or smooth cut. These questions are straightforward to answer for natural wood, where the fiber direction is consistent. However, composites have no grain direction, so neither crosscuts nor tears occur. Additionally, ensure that the blade is compatible with your saw, power capabilities, and the material you are cutting. Certain blades are tool-specific.
For ripping wood, a circular saw blade with a low number of teeth (usually around 24) and almost no bevel is suitable. These blades quickly remove large amounts of material but leave a rough finish. You can switch to a higher tooth count blade with a steeper bevel for final dimensions that require a smooth finish.
To prevent tearing when cutting end grain or wood fibers, choose a circular saw blade with higher tooth counts (60 to 100) and steeper bevels.
While the guidelines mentioned above often hold true, they are not universally applicable. For rough cuts, like framing, professionals often use a 24-tooth blade for its speed. As the wood will be hidden, there is no need for a flawless finish – just accurate measurements. If a better finish is required, opt for a higher tooth count blade. Although a high tooth count reduces cutting speed, it also minimizes the amount of finishing work needed.
Finding the Perfect Fit
Apart from the number of teeth, one of the most critical considerations when selecting a circular saw blade is the bevel angle. Let’s explore the bevel options based on the material and type of cut:
Flat Top Blades
These blades have no bevel and excel at removing large volumes of material during rough cutting, such as slitting or crosscutting.
Alternate Top Bevel Blades
These blades feature teeth that slope alternately in opposite directions (left/right). They produce clean cuts, with the quality improving as the angle increases. With a mid-range tooth count, these blades serve as excellent general-purpose options for ripping and crosscutting. However, they are not as effective as specialized blades for specific cutting tasks. That being said, for most cuts, you can find alternate top bevel blades that meet your needs.
Combination blades consist of alternating bevel teeth followed by flat-topped teeth. This design makes them versatile and suitable for various applications. The flat-topped teeth have larger gullets that efficiently remove material, while the bevel helps achieve clean cuts. Some manufacturers, like Diablo, are even experimenting with pointed teeth instead of flat ones in their third grind. Check out our review to see how well these blades work for framing.
High Alternating Top Bevel Blades
Blades with higher bevel angles produce extremely clean cuts with minimal tear-out.
Triple Chip Grinding Blades
These specialty blades alternate between flat-topped teeth and double-beveled or chamfered teeth. They are particularly suitable for cutting hard and composite materials.
We hope this article on selecting the right circular saw blade has cleared up any confusion, allowing you to choose the best accessory for your job. If you have any circular saw blade selection tips to share, feel free to add them in the comments below or join the conversation on Facebook, Instagram, and Twitter.