Positive rake tooth = weak
This is absolutely incorrect. Although a milled positive rake tooth doesn’t quite have the same cross-section or beef as a conventional tooth it does reduce the force that chips or strips a tooth. This clear advantage diminishes the loss of cross-section. A conventional tooth and a positive rake tooth do not need to have the same strength. When testing positive versus 0 rake teeth on a 4” round schedule 40 pipe, both teeth resisted stripped to the same degree.
For best results positive rake teeth band saw blades Canada should be used on difficult to cut materials.
Matrix band saw blades cannot run as fast as the M42 bandsaw blades
This is incorrect as band saw blade speed is limited based on the amount of heat the cut has generated. The temperature of the tool rip rises with the increase of speed and heat. This causes the tool to soften and therefore the ability to cut decreases.
High speed steel is generally used for the bandsaw blades as they are able to resist the softening effects of temperature better than other steels. The steel properties vary from steel to steel however M42 and Matrix are identical in softening at heightened temperature (red hardness). Theoretically, the M42 metal cutting bandsaw blade with a positive rake tends to have a reduced heat generation and therefore could have a higher band speed.
Only skip and took teeth should be used on large cross-sections (work pieces with long lengths of cut, because they have more gullet room than their conventional counterparts
The total gullet area for a hook or skip tooth is approximately 60% that of a conventional hook tooth. The usable gullet area of a hook or skip is only about 38% of a conventional tooth with the same pitch. Therefore, the appearance of a larger gullet is only an optical illusion.
D-2 must be cut dry
D-2 tool steel is a high carbon – high chromium steel. In its annealed condition it contains a large amount of carbide which makes it difficult to penetrate and therefore, work hardening can be severe because of its chemistry. Too much lubrication, from cutting oil, intensifies the problem. That being said, the grade can be cut with a water base soluble oil to help prolong the blade life.
Honed blades do not need to follow the break-in procedures
Testing has proven that break-in is beneficial and even essential for honed and unhoned band saw blades. Even though honing and breaking-in ar4e done to remove any sharp edges and burrs from the bandsaw tooth.
Band tension must always be set at 30,000 P.S.I.
This is untrue. For the majority of sawing applications a band tension of 30,000 P.S.I. is recommended. This is because blade tension makes straight cutting at a higher feed force easy. Increased tension, may lead to early fatigue or failure. Thus, an operator can adjust the band tension to suit their own needs.
Higher tensions such as 40,000 P.S.I or higher can be used to achieve straighter cuts and allow for higher speed force when tooth life is expected to be shorter and difficult material is being cut. For easy to cut workpieces where great feed force is not needed, a lower band tension can be used to prevent fatigue failure and aid in increase of tooth life.
