The drilling machine or drill press is one of the most common and useful machine employed in industry for producing forming and finishing holes in a workpiece.
The unit essentially consists of:
1. A spindle which turns the tool (called drill) which can be advanced in the workpiece either automatically or by hand.
2. A work table which holds the workpiece rigidly in position.
Working principle: The rotating edge of the drill exerts a large force on the workpiece and the hole is generated. The removal of metal in a drilling operation is by shearing and extrusion.
Common Faults:
I. Wrong usage of length that results in lesser leverage.
II. Substituting pliers for wrench.
III. Used as chisel or scraper.
IV. Used despite broken handles.
V. Replace blade that are not sharp enough.
