Countersinks

Along with general countersinking and deburring products, Alpha also offers decking countersinking, as well as combination drill and countersinking products, with flutes and angles made from premium HSS Cobalt/Aluminium (High-Speed Steel), TCT (Tungsten Carbide Tipped) or CRV (Chrome Vanadium).

Our range includes cross hole, single flute, three flute and five flute countersinks, as well as decking countersinks in HSS and TCT.

The combined drill and countersinking products also come in HSS or TCT. In addition, our Stepped Drill Bits are designed to pre-drill clearance holes through the first piece of material and pilot holes for the threads in the second piece of material. When you need varying countersink sizes you can also discover our countersink sets.

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What is countersinking?

Countersinking is the practice of enlarging and bevelling the rim of a drilled hole so that a screw, nail or bolt can be inserted flush against the workpiece. A countersink drill bit is a specially designed drill bit that creates space in the metal that corresponds to the shape of the screw head.

What are the specific applications and uses for Alpha’s countersinking products?

Single-flute construction provides less aggressive and slower cutting than multi-flutes, therefore reducing the risk of chattering. A single flute can be used for general-purpose countersinking and deburring on low-density materials, including mild steel, aluminium, softwood and plastic. Three-flute construction reduces chip load and controls chatter, which permits higher feed rates. Can be used for general-purpose countersinking and deburring in high-density materials, including mild steel, aluminium, hardwood and plastic. Five-flute construction provides optimum stability in hard materials for fast productivity with a fine finish. Perfect for stainless steel and recommended machine use for accurate speed and feed rates. Can be used for general-purpose countersinking and deburring on steel, stainless steel, wood and plastic. Cross Hole construction is the most universal product suiting the widest range of materials. Optimum deburring results are obtained in ferrous and non-ferrous metals. Optimum countersinking results are obtained in softer materials such as wood or plastic. Fluted countersinks are more suited for countersinking hard materials like steel, stainless steel, wood and plastic. Drill and Countersink combinations are ideal for decking, cement sheets, woodwork and steel (dependent on whether the product is TCT or HSS). Decking Drill and Countersink combinations are ideal for timber decking (hardwood and composite materials) and woodworking.

Countersinking feeds and speeds best practice

To determine optimum speed, start at the lower end of the speed range, then increase the speed until performance is maximised. It is important not to operate at an excessive RPM as chattering may occur, and the cutting area can overheat and become prematurely dull.