The countersinks (also known as small milling cutters or countersinks) are cutting tools used to form a conical recess at the mouth of an existing hole. Their main purpose is to allow the countersinking (milling) of a screw head, so that it sits "flush" with the surface of the material.
- Cutting Angles:90°: The most common angle for standard screws (metric thread).60°: Used mainly for edge "breaking" (deburring) and for centering.82°: Standard angle for screws according to American standards (UNC/UNF).
- Design Types:With hole (Zero Flute): Ideal for soft materials and thin sheet metal, as they do not "clog" and provide a very smooth finish.With 3 flutes (3-Flute): The most classic type for stable cutting without vibration in harder metals.
- Applications: In addition to countersinking screws, they are essential for removing burrs (deburring) after drilling, ensuring safety when handling components.
