How To Choose a Sawmill Blade Profile In addition to sawmill blade material, understanding the geometry and terminology of sawmill blade profiles is important. Here is an introductory guide in identifying different parts of a bandsaw mill blade and how to choose a blade profile that is best suited for your sawing application. Hook Angle and Back Angle Hook angle is the number of degrees that the tooth face leans forward of 90 degrees. Back angle is the number of degrees that the backside of the tooth leans backward of 90 degrees. The hook angle and back angle should be chosen based on the type of wood you are sawing and what type of equipment you are sawing with. • 10° Sawmill Blades - Most popular and versatile all-purpose hook angle with a 30° back angle for sawing softwoods, medium hardwoods, and hardwoods including birch, beech, red oak, cherry, walnut, soft maple, pine and poplar. • 9° Sawmill Blades - Ideal hook angle with a 29° back angle for lower horsepower (24HP or less) sawing in frozen wood, hardwood, and small diameter logs. • Turbo 747 Sawmill Blades - Only available from Wood-Mizer, this popular hook angle with an extreme 47° back angle for faster sawing speeds is compatible with all horsepower levels and features a deeper gullet capacity for increased sawdust removal and sharp penetrating points for increased accuracy when sawing softwoods and hardwoods. • Turbo 7° Sawmill Blades - Only available from Wood-Mizer, this high-performing hook angle with an aggressive 39° back angle is designed for higher horsepower (25HP or more) and higher feed rate sawing in extreme hardwoods including white oak, hickory, ash, hard maple and more. • 7° Sawmill Blades - Solid, all-around hook angle with a 34° back angle and additional gullet capacity for higher horsepower (25HP or more) sawing in hardwoods. • 4° Sawmill Blades - Lowest hook angle with a 32° back angle for sawing very hard, frozen, or partly frozen hardwoods with high density including acacia, beech, oak, hornbeam, and ash. • 12° Sawmill Blades - Ideal hook angle with a 28° back angle for sawing softwoods and resawing. • Vortex™ Sawmill Blades - Only available from Wood-Mizer, this unique dust-removal sawmill blade has more gullet capacity to remove sawdust from the board. Gullet The gullet is the area between teeth that captures and removes sawdust while providing strength in the tooth. The tooth height must be tall enough to allow the gullet to carry out all the sawdust from the cut. Tooth Height Tooth height refers to the distance from the lowest point of the gullet to the highest tip of the tooth. • Taller teeth (4°, 7° and Turbo 7° hook angle) provide more performance in higher horsepower (25HP / 18.4 kW or more) with increased sawdust removal. • Shorter teeth (9° and 10° hook angle) are better for lower horsepower (24HP / 18 kW or less), small log diameter sawing, resawing and secondary processing. Tooth Spacing Tooth spacing is the distance between each tooth from one tip to another. The pitch of a sawmill blade is also used in reference to tooth spacing as the number of teeth per inch or TPI on a bandsaw blade. • Shorter tooth spacing (1/2”, 5/8”, 3/4”) is used for low horsepower (24HP / 18kW or less) sawing and resaw purposes, or secondary processing. • Most common tooth spacing (7/8") is for all-purpose sawing and recommended for most portable sawmill equipment. • Wider tooth spacing (1”, 1-1/8", 1-1/4”) is for higher horsepower (25HP / 18.5kW or more) sawmills and high production. Tooth Set Tooth set is the distance the tooth is bent beyond the body or raker tooth of the blade. Tooth set clears a path in the wood for the body of the blade. Thickness Blade thickness is the thickness of the body of the blade without including tooth set. • Thicker blades (.045", .050", .055") provide faster feed rates and better cutting performance in difficult sawing conditions such as knotty, frozen, dry or extremely hard material, but require higher horsepower (25HP / 18.4kW or more). • Thinner blades (.035", .038", .042") provide longer flex life with lower horsepower (24HP / 18kW or less) sawmills where production or speed is not a primary factor. Width Blade width is the distance between the tip and base of the blade. • Wider blades (1-1/2” to 2”) are for higher horsepower (25HP / 18.4kW or more) sawmills and a faster feed rate. • Narrow blades (1” to 1-1/2”) are for lower horsepower (24HP / 18kW or less) sawmills and more difficult sawing. • Industrial wide blades (3") are available for wide slab industrial sawmills. Length Blade length is the distance between the ends of the sawmill blade before welding. Blade length is one of the most important information to know to make sure the blade will fit correctly on your sawmill equipment! Kerf Kerf is the width of cut made by the sawmill blade and includes the blade thickness plus tooth set measurements or the total amount of wood removed by the blade with each pass. Wood-Mizer thin-kerf sawmill blades remove less than 1/10” (2.5mm) of wood during the cut which produces about 20% more boards per log and less sawdust waste than traditional circular sawmill blades or chainsaw mills that remove up to 1/4” (6.3mm).