Choosing the appropriate circular saw blade for a woodworking task will improve the quality of the cut. Orientation of wood fibres, a.k.a. the grain, dictates style and placement of teeth on a saw. The ideal way to understand the tooth cutting profile is to hold a saw blade with the teeth facing you in the direction of the cut.
Crosscut Blade (best for cutting across the grain) When cutting across the grain, you want the saw to sever fibres like a knife. The tooth profile should be an acute angle bevel, which alternates from side to side, like a series of rotating knives. A crosscut blade has evenly spaced teeth of varying frequency. When teeth are more frequent on a blade, each tooth removes a smaller amount of wood, resulting in a smoother cut.
Ripping Blade (best for cutting parallel to the grain) When cutting parallel to the grain, you’ll want the teeth to be like chisels, so a rip tooth profile should be flat across the wood to plow out fibres. And the spaces between the teeth, called gullets, will be larger than on a crosscut blade, which allows strands of wood fibres to escape from between the teeth.
Combination Blade (best for general purpose cutting) If you need to alternate between crosscutting and ripping, reach for a combination blade. This hybrid means you won’t have to switch back and forth, all the while offering a decent cut. It’s ideal for coarse plywoods, where alternating grains mean you’re simultaneously crosscutting and ripping.
Regardless of blade type, when a cutter exits wood, any unsupported fibres are at risk of tear-out. Avoid this by not forcing a blade through a cut—use gentle pressure, and let the teeth do the work.
After use, especially with resinous woods, saw teeth will become caked with pitch. With the blade off, spray one side of the teeth with an all-purpose detergent cleaner, and let the resin soften for five minutes. Brush the teeth with an old toothbrush; flip and repeat. Rinse and dry the blade before remounting it.