How to Choose the Right Metal Cutting Band Saw Blade
Metal cutting band saw blades are designed with durability, precision and value in mind. These LENOX bi-metal blades are ideal for carbon steel, alloy steel, mold steels and structural steels.
It is important to match the tpi with material thickness for optimum cutting and minimal vibration. This is more important with tubes and profiles such as i-section beams than for solid materials.
Length
The length of a band saw blade is one of the most important features to consider when choosing a blade for your metal cutting bandsaw. You want to find a blade that is long enough to fit your project without being too short, as this can cause damage to your machine. A good way to determine the optimal blade length is by comparing the diameter of your bandsaw’s wheel with the blade size.
Once you know your wheel diameter, you can use a simple equation to calculate the blade length. To do this, measure from the wheel to the point where the blade starts. Then, mark that spot on the floor with a piece of tape. Then, roll the blade back and forth until it hits that mark again and comes to a stop. This will give you the blade’s length in inches.
The tooth set of a metal cutting bandsaw blade is another important factor to consider. It describes how the teeth are offset from the center of the blade and has an impact on raking effects for chip removal, smoothness of cuts, and blade binding. Some blades have a sequence of left and right offsets that vary in degree, while others have a straight offset.
Width
The width of a metal cutting band saw blade has a significant impact on quality and speed. If the width is too narrow for a material the teeth may be crowded together and cannot clear the cutting groove causing vibration, slow cuts and poor finish. Likewise, if the width is too wide for a material it can clog the blade and cause overheating.
Width can also be influenced by the material thickness, hardness and tooth configuration. For example, exotic woods require a finer pitch than soft steel cutting band saw blade woods. In general, the tpi is best matched to the material thickness for optimum cut quality.
It gets more complicated when working with tubes and profiles such as i-section beams, as the diameter of the tube or profile can impact the tpi recommended. This is because part of the cutting process occurs when the blade meets the thin wall head-on, requiring a fine cut to avoid vibration and damage. To compensate for this, a higher tpi is often required. Tooth set is also a factor as it influences the blade raking effect for clearing chips and the kerf width. A simple left / right straight sequence of offset teeth can be used for rapid material removal when finish is less important. Alternatively, variable offsets can be used to improve the raking effect and reduce chatter when cutting thin materials.
Pitch
The blade’s tooth pitch, or TPI (teeth per inch), is a significant factor that influences the kind Hardened & Tempered Steel Strip Supplier and quality of the cuts it makes. It is important to choose a tooth pitch that fits the workpiece’s thickness and the desired cutting speed.
It’s generally best to go with a variable pitch or set blade for metal cutting bandsaws, but there are many options for different applications. Ideally, a metal cutting bandsaw blade should be able to cut both thick and thin wall tubing.
To accomplish this, a bi-metal blade may be needed. These are heat-resistant and can take the stresses of cutting steel with ease. However, bi-metal blades need to be properly broken in for the best results.
The break-in process is a vital step in the proper maintenance of a metal cutting bandsaw blade. It allows the blade to adjust to the stress of the workpiece and the power of the machine. In addition, a well-broken-in blade will last longer and produce better cuts for an extended period of time. It will also help reduce the risk of the blade becoming dull. To check if a bi-metal blade is breaking in correctly, look for decent size chips being produced and a consistent rate of cutting. It’s a good idea to use a meter or tape measure to track the progress of the blade as it breaks in.
Teeth
The teeth of a band saw blade are one of its most critical components. They must be shaped, arranged and designed to best suit the application.
Metal bandsaw blades can be made from mild steel, alloyed or even bi-metal. The latter is a bandsaw blade that consists of a tough, flexible core with a wear-resistant layer fused or bonded to the tooth face. This combination allows you to cut a wide range of metals including carbon, alloy and hard-to-machine materials like stainless steel, tool steel and die steel.
Tooth shapes can be precision or claw/hook shaped, with the latter having a more aggressive rake angle and gullet shape. This enables them to chip away and break up material, reducing the risk of clogging, gumming and blade bounce.
When it comes to determining the appropriate tooth pitch, you need to take into account the material thickness as well as the workpiece geometry. For example, when cutting structural bundles of angle and solid workpieces the ideal TPI will be lower for the wider solid shape compared to the thinner arm of the angle.
It’s important to remember that if the workpiece geometry is not properly nested and clamped, stress will build up in the blade and machine. This can result in premature failure, such as bending of the blade core or stripping of the teeth. The good news is that using proper nesting clamps can significantly reduce this stress and the resulting problems.
