Core drills for metal: selection and application

To make recesses or through holes in a metal part, structure, plane, it is necessary to use metal drills. They all differ in shape, material, length and diameter. Among the types of such devices, one can distinguish core drills, which are quite an effective tool that fully fulfills its function.

The core drill appeared in the early 1970s and was invented by Diz Haugen. At first, such drills were not perceived by people and were ignored. Haugen offered his invention to various manufacturers, but they showed no interest in him. Only ordinary metalworkers got interested and decided to try the know-how in action.

At that time were used drilling machines with conventional drills, which were distinguished by a large mass, and at least two workers were required to work. During the drilling operation, there were a lot of inconveniences, and sometimes the worker was even thrown off the structure. After Haugen proposed the core drill, a lighter construction of the drill was created, which weighed about 13 kg.

What is a core drill? This name refers to a hollow attachment or nozzle that has the shape of an empty cylinder inside, designed to work with non-ferrous metals and steel. Core drills are designed in such a way that the recess is cut in the metal only along its contour, for this there is no need to use equipment with high power.

By drilling with such a drill, you can get a hole with excellent roughness in the inner part. This is very difficult to achieve with similarly designed tools. Ring fixtures are used in various types of equipment, and these are not only drilling, but also milling and turning machines.

You can also use them in conjunction with other tools, that is, perform multi-tool processing. This drill allows you to remove a large amount of metal being processed in one go. Thanks to the fact that the ring cutters are made of high-strength and high-speed steel, the work is carried out at high speed and maximum accuracy. During operation, annular cuts have minimal noise, and a large number of cutting edges in its working part ensure high productivity of this tool.

There are two types of these drills for metal: these are HSS teeth bits and carbide bits. Toothed bits are less productive and less expensive, and which are made of carbide materials are designed to work at higher speeds and are used for drilling carbide and high chromium steels.

The most budgetary ones are bimetallic bits for metal, their cutting part is made of a quick cut, and the main body is made of simple structural steel. Compared to conventional drills, crown counterparts have a fairly high cost.

• Core drills Kornor HSS Are reliable drills made of powder HSS steel with high efficiency. Designed to work with all types of stainless steel structures. There are these types of shanks: One-touch (universal) - designed for most drilling and magnetic drills, including Weldon19. Weldon and Quick shank for Fein drilling machines. They are useful for work in any conditions, provide a long service life. Smooth cutting and minimal vibration are ensured thanks to the double edge of the blades. The sharpening of the drills is reusable, which significantly saves you money and extends the service life. Work is carried out more precisely and faster thanks to the ejector pins. They can be used in vertical drilling, radial drilling and vertical milling machines thanks to the wide range of adapters. One-ouch drills are available in diameters from 12 to 100 mm and provide depths up to 30 mm, 55 mm, 80 mm and 110 mm.

• Core drill Intertool SD-0391 has the following parameters: height 64 mm, drill diameter 33 mm. Designed for tile cutting. Weighs 0.085 kg. Made of tungsten carbide chips. Works great on ceramic and tile tiles, as well as bricks, slate and other hard surfaces. Provides through holes with centering pin only. They are used in conjunction with a screwdriver, lightweight hammer drills that work in a hammerless mode, and drills. Thanks to the tungsten carbide alloy, the drills are resistant to continuous loads and provide a long service life. Thanks to this design of the drill, the hole is smooth.

• Metal core drill MESSER has a diameter of 28 mm. Designed for installation on any equipment. Differs in a rather large area of ​​contact between the cutting edges of the drill and the workpiece. Such a drill will allow you to remove a large amount of work material at a time. This will require less energy and power of the equipment used.

• Ruko solid carbide core drill used to work with power drills and vertical drilling machines. When working on a vertical machine, only manual feed is used. Can work with stainless steel (up to 2 mm thick), light non-ferrous metals, as well as plastic, wood and drywall. Provides high rotation accuracy and stable structure. Can be sharpened, drills to a depth of 10 mm with a material thickness of 4 mm. Not intended for use with a hammer drill. While working, it is necessary to apply a slight uniform force, avoiding lateral displacements during drilling.

To select a crown for metal, it is first of all necessary to take into account all the production tasks for which this drill is purchased. You need to know what you want to get the depth and diameter of the hole, as well as what type of metal or other solid material it will be used for. Each drill has a series that indicates which type of drill the drill is intended for. Consider the bit material and roughness, as well as the alignment method.

If you plan to use the tool for a long time, then it is better not to save money, but to choose a drill from a trusted manufacturer with good technical characteristics. Inexpensive drills are distinguished by good elasticity, designed for drilling holes with a diameter of 35 mm in products that have a low density.

Core drills are very often used to make through holes in metal, wood, plastic and chipboard, as well as many other hard materials. Thanks to simple technology and minimal use of force, it is possible to obtain a correct hole shape even in concrete and natural stone, in any building structures. Without damage, you can make a round hole in tile, glass or other fragile material. It is widely used during horizontal drilling of various utilities. For working with concrete, core drills are used, which are diamond-coated or brazed. They come in two groups: with a load of up to 5 MPa and up to 2.5 MPa.

You can learn how to choose metal core drills from the video below.