What Are Step Drill Bits Used For?

Those who work in mechanical workshops and in carpentry have certainly met the step drill bits, tools also known as step drills or conical bits that are used together with a drill to bore and allow you to achieve an important result: you can quickly make holes with different diameters without changing the drill tool.

These solutions are very useful for working on thin surfaces, such as metal sheets or plastic films, but they cannot be used for demanding work such as drilling concrete or a block of stainless steel. But in some cases it can make a difference.

What are step drill bits?

Step drill bits or conical bits are fundamental tools in a tool box that present several blades.

They have a shape that allows you to create holes that become increasingly larger thanks to a gradual increase in diameter along the body of the tool.

Each section is a step that further enlarges the hole, in this way it is possible to increase the width without changing the drill tool. Fundamental advantages: they allow you to save time while maintaining a high quality standard.

Why are they used and when

The use of conical drills is mainly linked to the drilling of metal sheets and plastic profiles. These tools are perfect for creating large holes on rigid and thin surfaces, such as a plate or a door. In some cases you have models available that allow you to drill and countersink the material at the same time and speed up the operations even more.

You must make a distinction between conical drills and step drills: in the first case we are mainly talking about those in pyramid shape that have different drilling diameters while step drills are designed for hole enlargement. That is, to create a first hole and then a step of different diameter: unlike the countersink which is conical, in this case we have a cylindrical machining.

Structure and realization of drill bits

Basically, step drill bits are made from HSS. That is, high-speed steel. This solution is perfect for working on hard and difficult structures: high-speed metal is perfect for intensive work. Some drills are coated with titanium nitride (TiN) to increase wear resistance and improve durability. Here is a representation taken from the Krino catalog.

The Krino models are perfect for making precise cylindrical holes on tubes and steel sheets, aluminum, plexiglass, light alloys, plastic and other metals of different thicknesses. The non-slip shank offers maximum grip, the lateral groove guarantees high performance. Especially when the work is accompanied by an excellent lubricating oil.