Tool Lab | Understanding Saw Blades

In Tool Lab, Nathan Gilbert talks all about saw blades. Having the right blade can significantly impact the table saw’s performance, quality of the cut, and safety.

He explains that the stock blades on a table saw are for general use and not the best quality. Table saw blades come in three categories: ripping, cross-cutting, and combination. Nathan then goes into the blade anatomy, explaining the difference in teeth, kerf thickness, and coatings are designed to impact the cut. Nathan describes the variations in tooth geometry and how the teeth are cut in various patterns for specific types of cuts and materials.

Nathan shares his advice on picking the best table saw blade while sticking to your budget. Table saw blades are broken down into three categories: ripping, cross-cutting, and combination.

Saw Blade Anatomy

Table saws are comprised of the following:

Steel Plate—the main body.

• Throughout the plate are various cuts to reduce noise and vibrations or expand the blade as it heats.

Carbide teeth

• Pricier blades have large, thick teeth made of the hardest carbide and can be re-sharpened multiple times.
• Less-expensive blades have thinner teeth and softer carbide and don’t typically do well with sharpening.
• The space between the teeth is called the gullet. This area helps remove chips and shavings as material moves throughout the cut.
• Ripping blades typically have fewer teeth and larger gullets. Crosscut blades have more teeth and smaller gullets.

Arbor hole—the hole in the center of the blade, connecting to the arbor.

Kerf thickness—the line of material taken away as the blade cuts through the stock.

• If you’re running a portable saw, thin-kerf blades are a great option, especially if you’re often finding the saw bogs down.

Coating—coatings like Teflon are added to the blade to help keep the heat down and make the blade run through the material easier.

Tooth Geometry

Flat Top Grind (FTG)

• The tooth has a flat top on it. These teeth hold their edge well and are ideal for ripping wood quickly.
• FTG blades can leave kerf marks on the material, which will require sanding or jointing.

Triple Chip Grind (TCG)

• Teeth that are ground down on the corners, which lessens the opportunity for kerf marks.
• TCG teeth are found on glue-line rip blades- which provide the best finish.
• These blades will often have FTG in the mix to aid in ripping.

Alternate Top Bevel (ATB)

• Found on cross-cutting blades.
• The teeth are beveled in opposite directions, making for a much cleaner cut across the grain.
• The steeper the bevel, the cleaner the cut.

High Angle ATB blades (Hi ATB)

• The bevel angle on these is very steep, creating a very fine point.
• These blades are ideal for ripping finish-veneer plywoods. Great for making cabinets and furniture.
• They dull more quickly than any other blade type, so you should only use them for plywood. Don’t cut framing lumber with it.

Combination or general-purpose

• As the name implies- a mixture of ripping and cross-cutting.
• These blades have a variation of ATB teeth mixed with an FTG raker tooth and deep gullet to help with ripping tasks.

All the blades also have a hook angle, which refers to the angle of the tooth in relation to the center of the blade. Higher hook angles make a more aggressive cut. Rip blades have higher hook angles and work best on harder, denser woods. Cross-cutting blades often have lower hook angles and work best on softer woods.

Nathan’s Advice on Saw Blades

• Manufacturers will typically specify what material type a blade is best for. They will also give material thickness ranges- which take into account tooth geometry and hook angles, so be sure to read those specifications provided by the manufacturer.
• Unless you’re a woodworker and have a cabinet saw, owning a separate blade for all of your table saw tasks likely isn’t worth the investment in time or money.
• If you use your table saw for various projects and a variety of materials—and you’re on a tight budget- then investing in a good-quality combination or general-purpose blade is a good move. You won’t get glue-line quality rips or flawless plywood veneers- but you will get all of the jobs done.
• Having a separate blade for cross-cutting on the table saw most likely isn’t needed unless you’re a woodworker. Most people can get away with using their miter saw blade for cross-cutting.
• When it comes to blades, you often get what you pay for—not necessarily in terms of quality—but in terms of consistency of cut over time.