A magnetic drilling machine is a portable drilling machine with a magnetic base (either electromagnetic or permanent magnet). It can use twist drill bits, annular cutters , milling cutters, and other rotary cutters. With suitable bits it can also tap threads, ream, and countersink. Its combination of a stable magnetic base and low RPMs help resist or reduce torque forces created by large diameter bits. 
A portable magnetic drilling machine is faster and more portable alternative to hole making machines such as the drill press, and is more accurate than a hand drill.
A portable magnetic drilling machine is used on steel or other magnetic materials. It gives an accuracy of 0.01 mm to 0.05mm in steel or other magnetic materiel. The drill bits used for this machines are generally made from high-speed steel(HSS) or are tungsten carbide tipped(TCT).
The base of a magnetic drill is equipped with a powerful electromagnet to easily clamp the machine on the work piece to be drilled. When energized this magnet is held on the metal work piece locking the machine base to the surface. The electromagnet plays a very important role in a portable magnetic drill, as it helps the machine to be steady, does not let the machine dismount during drilling, can work with the machine overhead, horizontal or vertical. Generally, a magnetic core drilling machine is used on a ferrous material directly, but it can also be used on non-ferrous material like aluminum with the help of clamping devices.
A drill stand is the main body of the magnetic drill where the electric switches for motor and magnet are mounted, magnet indicator is mounted and also the clock-anticlockwise direction switches are mounted. The body of the magnetic drill holds together the motor and the magnet base. The feed handle is also attached to the body. The body of the magnetic drill helps the motor slide on it to get an upward and downward feed. The body of the magnetic drill also plays the role of a handle to lift and move the machine from one place to other. The material used for the body is generally cast iron.
An arbor or chuck on a magnetic drill is attached to the motor. it is a type of clamp used to attach the core drills. There are mainly two types of chuck available for the magnetic drill, industrial arbor (manual tightening) and quick change drill chucks. The quick change drill chucks are easy and fast option to attach the core drills. They do not need to tighten the screws/jaws manually. The arbor or chucks have different types of spindle holder (machine taper) like Morse taper MT 2, MT 3, and MT 4.The BDS MAB 1300 core drilling machine is the only machine in the world with MT 4 tool holder. The chuck allows different types of core drill shafts (shanks) to fit in it