Precision Twist Drill 5998146 Cobalt Drill Bit 1/64 in

Product Description

The PRECISION TWIST DRILL 5998146 is a cobalt jobber-length drill bit engineered for heavy-duty drilling applications in ferrous and non-ferrous metals. At 1/64 inch (0.0156 inch) in diameter, this right-hand, two-flute bit features a 135-degree split point that reduces walking on entry and lowers the thrust required to start a hole. The straw oxide and bronze coating adds surface hardness and mild corrosion resistance. With a 3/4-inch overall length and a 3/16-inch flute length, this is a purpose-built micro drill intended for precision metalworking tasks where accuracy in tight tolerances is critical.

This drill bit is suited for production and maintenance drilling in steel and a broad range of workpiece materials including cast iron, non-ferrous alloys, heat-resistant alloys, and similar metals. Its cobalt construction handles higher cutting temperatures than standard HSS, making it a practical choice for harder steels where conventional bits wear prematurely. Machinists, toolmakers, and trade professionals working with CNC machines, drill presses, or precision hand-held equipment will find this bit appropriate for fine-detail through-hole work. The series designation is R10CO-R15CO-R18CO. The straight shank and standard point geometry make it compatible with standard collets and chucks sized for 1/64-inch shanks.

Key Features

• Cobalt construction for elevated heat resistance when drilling harder steels
• 135-degree split point reduces bit walking and lowers entry thrust
• Straw oxide and bronze coating provides surface hardness and mild corrosion resistance
• Web-thinned, tapered web design reduces cutting resistance through the full flute depth
• Meets ANSI standards and NAS 907 specification
• Right-hand, regular spiral flute suitable for general-purpose through-hole drilling

Compatibility

Designed as a general-purpose OEM-style replacement or production drill for use in any standard chuck or collet accepting a 1/64-inch straight shank. Compatible with material codes P, M, K, N, and S per the input specification, covering steel, stainless, cast iron, non-ferrous metals, and heat-resistant alloys.

Installation Notes

Installation is performed by machinists or tool technicians in shop or field environments. Secure the straight shank in a properly sized collet or drill chuck before operation. Always run at appropriate spindle speeds for the workpiece material and bit diameter; micro drill bits are sensitive to side-load and runout, so chuck concentricity is critical. Do not apply excessive feed pressure, which can snap a bit of this diameter.