A spiral flute tap, also known as a spiral point tap, is a type of cutting tool used for threading holes in materials, such as metal and plastic. It is designed with flutes that spiral up the tap, typically at a shallow angle relative to the tap's axis. This design feature sets spiral flute taps apart from the more common straight flute taps.

Key characteristics and advantages of spiral flute taps include:

Chip Evacuation

The spiral flutes help in effectively evacuating chips from the hole as the tap advances. This is particularly useful when working with materials that tend to create long, stringy chips or when deep-hole tapping.

Reduced Tapping Torque

Spiral flute taps generally require less torque to cut threads compared to straight flute taps. This is because they have less contact with the workpiece at any given time, reducing the friction and the force required to turn the tap.

Suitable for Through-Hole Tapping

Spiral flute taps are often preferred for through-hole tapping, as they help prevent chip buildup and allow chips to be pushed out of the hole, making the process more efficient.

Less Tendency to "Push"

These taps have less tendency to "push" or force the workpiece material ahead of the tap as it cuts, which can result in a smoother threading process.

Increased Tapping Speed

Due to their design, spiral flute taps are well-suited for higher-speed tapping operations, making them ideal for use with high-speed machining centers.

It's important to select the appropriate type of tap, whether it's a spiral flute tap or another type, based on the specific threading requirements and the material being worked on. Different taps are designed for various applications, such as blind-hole tapping or through-hole tapping, and the choice of tap depends on factors like material type, hole depth, and the desired thread specifications.