Counter boring: Counter boring is the operation of enlarging one end of an existing hole concentric with the original hole with square bottom. It is done to accommodate the heads of bolts, studs and pins. The cutting edges of the counter–bore (tool used for counter boring) may have straight or spiral teeth.
Beside this, what is counter drilling?
1. counter–drill – drill in an opposite direction. drill, bore – make a hole, especially with a pointed power or hand tool; “don’t drill here, there’s a gas pipe”; “drill a hole into the wall”; “drill for oil”; “carpenter bees are boring holes into the wall”
Secondly, what is difference between hole and bore? As verbs the difference between hole and bore is that hole is to make holes in (an object or surface) while bore is (senseid)to make a hole through something or bore can be (bear).
Likewise, what is counter sinking and counter boring?
A countersink is a cone-shaped hole that is cut into the PCB to allow the flat head of a socket cap screw to fit flush with the surface of the board. A counterbore is a cylindrical flat-bottomed hole that is designed to house a hex head or socket head cap screw to be used to secure a PCB board.
What is miscellaneous operation on the drilling machine?
Description. Drilling machines, or drill presses, are primarily used to drill or enlarge a cylindrical hole in a workpiece or part. The chief operation performed on the drill press is drilling, but other possible operations include: reaming, countersinking, counterboring, and tapping.