Drills for different tasks
- Click on the links below to learn
more about the different types of
In addition to the basic types of drills(High-speed steel-, Solid carbide- and Indexable type drills), there are a number of special drills used for different tasks, for instance finishing and machining of printed circuit boards.
Gun drills can machine deep holes with a depth of up to 300 times the drill diameter in one process. In addition, gun drills are used for various drilling applications as they are able to make high accuracy holes and are suited to small-diameter, deep hole drilling.
Deep hole drilling is possible due the high pressure supply of internal coolant. In general, gun drills are often used with an exclusive machine called gun drill machine. Gun drill machines feature a high-pressure coolant device to supply coolant, a guide bush and a rest bush to hold the gun drill in order to prevent vibration when the gun drill engages a workpiece.
Gun drills with one or two cutting edges are generally used. Gun drills with one cutting edge can machine all materials, while those with two cutting edges can be used mainly for machining cast iron and aluminium alloy.
Bush to prevent vibrations
of a shank
Centre drills are used for drilling a centre hole.
Core drills do not have a centre cutting edge. They are used for the finishing of a prepared hole, or for the preparation of a prepared hole for a reamer.
Spade drills are straight flute drills with the plate type cutting edge. They are generally used with a cutting edge that is located into a holder.
Drills that are used for the machining of PCB (printed circuit boards) are straight shank drills whose drill diameter and shank diameter are different. They are used for the drilling of very small diameter holes.