90° HSS Cross-hole Countersink Cutter Set
cross-hole countersink is a cone-shaped tool with a cutting edge provided by a hole
that goes through the side of the cone. The intersection of the hole and cone form
the cutting edge on the tool. The cone is not truly symmetrical as it is essential
that the cone retreats away from the cutting edge as the tool rotates. If this does
not occur the cutting edge will lack clearance and rub rather than bite into the
material. This clearance is referred to as cutting relief.
These tools are best used as deburring tools, where the burr from a previous
machining operation needs to be removed for cosmetic and safety reasons, however
they may be used in softer materials (such as wood or plastic) to create a countersunk
hole for a screw.
common use is to allow the head of a countersunk bolt or screw, when placed in the
hole, to sit flush with or below the surface of the surrounding material. A countersink
may also be used to remove the burr left from a drilling or tapping operation thereby
improving the finish of the product and removing any hazardous sharp edges.
Regardless of the name given to the cutter, the surface being generated may be
a conical chamfer (plunging applications) or a beveled corner for the intersection
of two planes (traversing applications).
A countersink is a conical hole cut into a manufactured
object. The same term is used for the cutter used to cut such a hole.