The variable pitch bandsaw blades, their unique qualities and applications, are designed for a particular reason. In this case, it is pitch. Saw blade pitch is defined as the number of teeth per inch — TPI — the number of teeth that come in contact with the material being worked.
TPI has the ability to affect both the bandsaw blade’s performance and it durability.
Too few teeth in the cut can lead to early stripping of the teeth. Conversely, too many teeth in a cut will greatly reduce the cutting rate and ultimately make the material impossible to cut.
The choice of correct tooth pitch can be decisive when it comes to things like achieving the optimum performance of the bandsaw and cutting of subsequent cross-section materials.
The description of a constant-pitch bandsaw blade indicates a uniform distance from one tooth tip to the next while a variable-pitch blade’s teeth distance is within a group of teeth. The smallest and the largest tooth pitch denote the variable tooth of the saw blade. This may sound elementary to experienced people in the band sawing industry, but after hearing from a variety of customers — those with a broad and varied level of experience in the industry — the same question is still asked: When is a variable-pitch bandsaw blade used?
A constant-pitch saw blade can increase harmonic vibrations. Harmonic vibrations can lead to excessive noise, undesirable saw or saw blade vibrations, and in severe cases, a bad cut.
A variable-pitch saw blade, with teeth that vary in gullet depth, set angle and pitch, can greatly reduce harmonic vibrations. With varying tooth space, sawing rhythms are interrupted, chip evacuation is improved, and vibration is reduced, resulting in less noise and a better overall cut.
This becomes particularly effective when cutting odd shaped materials that are more likely to produce vibration. Vibration in the cut will significantly shorten the life of the bandsaw blade.
A variable-tooth set will also help to reduce the tooth stripping that occurs when cutting hard materials. It also offers high heat, wear, and shock resistance. These allow for a broader range of application use when cutting metal. The combination of all factors results in the longest blade life among similar types of saw blade.
When combined with positive rake, the variable-pitch bandsaw blade has no equal due to its faster work penetration and increased sawing productivity.