Sometimes called spotfacers, use counterbores to create contoured holes for a precise fit when seating ports, fasteners, or other parts in the hole. The pilot (tip) of the counterbore is the same diameter as the existing hole and keeps the counterbore accurately centered during drilling.
Cap Screw Counterbores
Create a cavity at the top of an existing hole to seat the head of a socket head cap screw or shoulder screw so it is hidden or sits flush with the surface.
Also known as porting tools, these counterbores will machine contoured ports into a workpiece. They are designed with all the necessary features and dimensions of the port built into the tool except the depth, which is controlled by the machine.
UNF Thread Standard
UNJ Thread Standard
Cap Screw Counterbore Sets
Have the right tools on hand to create counterbored holes for a range of standard cap screw sizes. These sets contain multiple counterbores in different sizes.