Introduction
★ What Is a Chip Breaker Drill Bit?
A chip breaker drill bit looks much like a standard twist drill at first glance, but the cutting edge tells a different story. Ground into the flute or cutting lip is a series of small notches — the chip breaker geometry. As the bit cuts, these notches physically interrupt the chip before it can form into a single, continuous spiral ribbon.
This matters most in materials that don't break their own chips naturally. Stainless steel and other ductile alloys tend to produce long, stringy chips that wrap around the flutes, jam in the hole, or drag across the freshly cut surface — scratching the bore and increasing friction at exactly the point where heat buildup is already a problem. By breaking the chip into short, manageable segments as it forms, the chip breaker keeps the flutes clear, improves chip evacuation up and out of the hole, and reduces the chance of re-cutting already-removed material. The result is a cleaner hole, more consistent cutting forces, and less operator intervention during continuous drilling runs.
★ Why a Tri-Flat Shank?
From 5mm and above, this drill bit uses a tri-flat shank instead of a standard round shank. The three ground flats increase the contact area between the shank and the chuck jaws, giving the chuck significantly more grip on the same clamping force.
This matters specifically at larger diameters, where cutting torque is highest and a round shank is more prone to spinning in place inside the chuck — a slip that chews up the shank, stalls the cut, and wastes the hole already started. The tri-flat design resists that rotational slip without requiring the operator to over-tighten the chuck, which in turn reduces wear on the chuck jaws themselves. Below 5mm, where torque loads are naturally lower, a straight shank provides sufficient grip without the added manufacturing step.
★ Why HSS-M35 Cobalt for Stainless Steel?
Stainless steel is difficult to drill for two compounding reasons: it work-hardens quickly when cutting pressure is inconsistent, and it conducts heat poorly, so cutting temperature concentrates right at the edge instead of dissipating into the workpiece. A standard M2 bit can handle stainless steel in short runs, but edge wear accelerates once temperature climbs.
HSS-M35 addresses this directly. The added cobalt content allows the cutting edge to retain its hardness at significantly higher temperatures than M2, so the edge keeps cutting cleanly even as friction heat builds during extended or high-volume drilling. Cobalt also raises the overall hardness and abrasion resistance of the steel itself. In practice, this translates to longer edge life, more holes per sharpening, and more predictable performance when working through stainless plate, sheet, and structural sections — exactly the conditions where M2 edges dull fastest.
★ Primary Applications
The combination of cobalt edge retention and chip breaker geometry makes this bit suited to production and maintenance environments where stainless steel and other tough, ductile materials are a regular part of the workload:
• Stainless steel fabrication — sheet, plate, and structural sections in kitchen equipment, food processing, and architectural metalwork
• Marine and corrosion-resistant components — fittings, brackets, and hardware where stainless is specified for environmental durability
• Medical and food-grade equipment manufacturing — applications where stainless is standard and clean, accurate holes matter
• General metal fabrication shops — mixed-material environments where the same bit needs to perform reliably across stainless and other alloy steels
• Industrial and MRO maintenance — repair and retrofit work on stainless components where chip control reduces rework and surface damage
★ Material, Shank & Packaging Options
Material — Available in HSS 4341, HSS-M2, and HSS-M35 (cobalt), selected by the diameter and material demands of the job.
Shank Type — Straight shank (Ø1mm–4.9mm) for standard chuck compatibility at smaller diameters; tri-flat shank (Ø5mm and above) for secure, slip-free clamping at higher torque loads.
Finish — White/bright finish (uncoated, M2) for general-purpose runs; amber finish (M35 cobalt) for stainless and high-heat applications; black oxide for added corrosion resistance and reduced friction during the cut.
Packaging — Single size, full metric sets (1–13mm), or OEM/private label packaging available — contact us with your volume and specification requirements.
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