How Very Small Spiral Fluted Drills are Manufactured and Used

Drill bits, especially those with spiral fluted designs, have a rich history. The earliest version, invented by Steven A. Morse in 1861, was created using a simple yet effective method. This article explores the manufacturing process of very small spiral fluted drills, from the early methods to today's advanced techniques.

The Evolution of Twist Drill Bits

The invention of twist drill bits by Steven A. Morse set the foundation for modern drilling technology. Initially, the manufacturing process involved cutting two grooves on opposite sides of a round bar and then twisting the bar to create helical flutes. This method provided a basic but functional design. Over time, advancements in manufacturing techniques have transformed the process.

Current Manufacturing Techniques

Modern manufacturing of twist drill bits, including very small ones, is achieved through a sophisticated process. A round bar is rotated while simultaneously moving it past a grinding wheel. This method, similar to the one used for cutting helical gears, ensures precise and consistent flute formation. This process is capable of producing drill bits ranging from 0.002 inches to 3.5 inches in diameter (0.051 to 88.900 mm). Even the smallest bits, like the 0.56 mm drill bit—11 times smaller than 1/64 inch—can be manufactured with high precision.

The Challenge of Super Small Bits

Diverse applications often demand extremely small drill bit sizes. While some may assume that creating these tiny bits is particularly challenging, the manufacturing rules and techniques remain consistent. Current technology allows for twist drill bits as small as 0.0135 inches in diameter (80 on the Rockwell hardness scale). This capability extends to the precise drilling required in printed circuit boards (PCBs), where holes as small as 15 mils (0.015 inches) are routinely drilled.

Conclusion

The manufacturing of very small spiral fluted drills is a testament to the advancement in drilling technology. From simple early methods to today's highly precise techniques, the process has evolved significantly. As technology continues to advance, the ability to manufacture and use extremely small drill bits will only grow, catering to the demands of various industries, including electronics manufacturing.