Drill Bits & Countersinks

Class B Bronze drill bits are the workhorses of glass drilling operations. Featuring a bronze-alloy body with an industrial-grade carbide cutting tip, these bits deliver consistent performance across a wide range of glass types and thicknesses. The bronze body serves a critical function beyond structural support — it acts as a heat sink, drawing thermal energy away from the carbide tip during drilling. This thermal management prevents the tip from overheating and losing its edge, extending the useful life of each bit. The flute design efficiently evacuates glass swarf from the hole, preventing clogging and reducing the risk of glass cracking due to trapped debris. Class B bits are the go-to choice for production environments where reliability and cost-per-hole matter more than ultimate precision.

Class A Grooved drill bits represent a significant step up in drilling precision and hole quality. The defining feature is the precision-machined groove running along the body of the bit — this groove serves multiple engineering purposes. First, it reduces the contact area between the bit and the glass, lowering friction and heat generation. Second, it creates an additional channel for coolant delivery directly to the cutting zone. Third, it provides a path for fine glass particles to escape, preventing buildup that can cause bit binding or glass cracking. The carbide tip is ground to tighter tolerances than Class B, producing holes with smoother walls and more accurate diameters. For operations where hole quality matters — visible hardware, precision assemblies, or coated glass — Class A Grooved bits are the preferred choice.

Class AA Grind-Free drill bits are the pinnacle of glass drilling technology. The term 'grind-free' refers to their ability to produce holes so clean and precise that no subsequent grinding, polishing, or finishing step is needed. This is achieved through a combination of ultra-precise carbide tip geometry, nano-scale surface treatment, and a patented self-centering point design. The tip geometry creates a compression cutting action rather than an impact action, which produces holes with virtually no micro-cracking or chipping at the entry and exit points. The nano-scale surface treatment reduces friction to near-zero levels, preventing heat buildup and glass deformation. For high-end architectural glass, automotive applications, and precision instrument panels, Class AA bits deliver production efficiency that justifies their premium cost — by eliminating an entire downstream processing step.

Countersink and combination drill/chamfer tools solve a critical efficiency problem in glass processing: the need to create holes that accept flat-head screws, bolts, and other flush-mount hardware. Without countersinking, hardware protrudes from the glass surface — both an aesthetic and safety issue. Hanwin's combination tools drill the through-hole and create the countersunk recess in a single pass, eliminating the tool change and realignment that separate operations require. The countersink geometry is precisely matched to standard hardware angles (typically 90° or 120°), ensuring perfect flush fit every time. Dedicated countersink tools are available for operations where existing holes need chamfering — deburring entry/exit edges, creating lead-in chamfers for assembly, or preparing holes for specialized fasteners. Both types feature the same premium carbide construction as our drill bit series.