Accupro A-6120055R Micro Drill Bit 0.55 Mm Solid Carbide

Product Description

The ACCUPRO A-6120055R is a solid carbide micro drill bit designed for precision drilling in tight-tolerance applications. The 0.55 mm diameter cutting edge delivers accurate, repeatable hole sizing where standard miniature tooling cannot reach. A 120-degree point angle promotes self-centering on entry and reduces walking on hard or brittle workpiece materials. The bright, uncoated finish is suited for applications where coating buildup tolerance or compatibility with certain cutting fluids is a concern. This bit is intended for use by machinists, toolroom technicians, and precision fabricators working with CNC equipment or sensitive manual drilling setups.

This micro drill bit belongs to ACCUPRO's Miniature series and is sized for fine work in electronics fabrication, watchmaking, medical device manufacturing, instrument assembly, and other fields requiring sub-millimeter hole geometry. The straight-cylindrical shank with a 1.00 mm diameter seats cleanly in collet-style chucks and micro drill holders. The 25 mm overall length keeps deflection low during high-speed, small-diameter drilling operations. Coolant-through capability is not supported, so flood or mist cooling applied externally at the cutting zone is the standard approach.

Key Features

• 0.55 mm cutting diameter for sub-millimeter hole applications
• Solid carbide construction provides rigidity and wear resistance at high spindle speeds
• 120-degree point angle reduces entry walking and improves centering on flat or curved surfaces
• Spiral flute with regular helix promotes chip evacuation in shallow-to-moderate depth holes
• Bright, uncoated finish compatible with a wide range of cutting fluids and workpiece materials
• 1.00 mm straight-cylindrical shank fits standard micro collets and pin vises

Compatibility

Designed as an OEM-style replacement and standard tooling option for micro drill applications requiring a 1.00 mm straight-cylindrical shank and 0.55 mm cutting diameter in Miniature-series drill holders and collet chucks.

Installation Notes

Micro drill bits of this diameter are installed by toolroom machinists and precision CNC operators using collet chucks or micro pin vises rated for the 1.00 mm shank diameter. Always confirm runout on the holder before use, as even minor misalignment at this scale significantly increases breakage risk. Power down the spindle completely before changing tooling. Avoid side loading or hand-feeding pressure that exceeds the programmed feed rate, as solid carbide micro bits are brittle and will snap under lateral stress.