Everything you need to know about long metal drills

When choosing drills for metal, the user must take into account certain nuances, since these products have their own characteristics. Regardless of whether a particular drill will be used at home or in production, it should be chosen taking into account the material on which the corresponding work is planned to be carried out.

In this article, we will get acquainted with the characteristics of long drills for metal. This knowledge will help in choosing them when the need arises.

When choosing a long drill for metal, it is necessary to take into account the type of metal that will be drilled. It will not be difficult for a specialist to select the appropriate nozzle, taking into account the weight, length, color and markings. A novice user will have to deal with some of the features of such a device. Long drill options designed for through and blind holes in cylindrical parts with a large length.

A long drill bit for metal must be quite strong to avoid kinking during operation. Such a nozzle is from 1 to 20 mm in diameter and from 56 to 254 mm in length. Compared with standard products, the angle at the top of the cutting edges in the long version is increased and amounts to 135º (in the usual - 118º). This feature makes it possible to work with heavier materials, eliminating unnecessary stress on the tool.

Long drills can differ significantly from each other in the design of the shanks. There are tools with cylindrical and tapered shanks. The first are thin cylindrical metal rods. Four grooves are placed on their surface (2 screw and 2 spiral) - they are needed for cutting material and removing chips.

Cylinder drills are used for drilling steel, wood and non-ferrous metals. They can be left-handed or right-handed, but the first option is more common. According to GOST, these devices are manufactured with a centering recess, but some of them can be manufactured without it.

Cylindrical drills are sometimes made with a small neck to facilitate grinding. The total length of these drills can be up to 320 mm.

Tapered shank models are considered to be the preferred choice among professionals. They fit securely into the drill chuck while providing the most accurate centering during operation.

The tapered shank type avoids burrs and irregularities in the material when drilling. The upper part is completely smooth at the end, the walls of the drilled holes will also be smooth.

The conical type devices have the most convenient design, which allows, if necessary, to replace them with a new model. Such tools are used for drilling metal. But they can work with wood or plastic.

Using these drills, you can make holes of different diameters in alloy or carbon steel, cast iron, sintered alloys, non-ferrous metals.... The fastening of the drill itself with a tapered shank is carried out thanks to the adapter sleeve. Fixtures of this shape are manufactured with a spiral working part.

There are several varieties of long metal drills, which differ in strength, fixing part to equipment, cutting part and working surface for chip removal.

Next, we will consider the most common models of extended nozzles in more detail.

1. Brushed metal version, having a conical shank. This type is suitable for working with products made of building and structural metal or cast iron. The drills are made of high speed steel HSS and have a sharpening angle of 118º.

2. Cutters made of quick cut, have an admixture of cobalt, and are covered with a titanium-nitrite layer on top. They are used in work with steel parts with the highest strength (900 N / mm²).

3. Extra-long and long metal elements. They are equipped with cylindrical shanks and have a reinforced stem. For efficient chip removal, a parabola-shaped spiral groove is made in this version. This type of drill is characterized by increased rigidity.

4. Pointed spiral nozzle, with a long or extra-long size. Has a taper shank. This option is used for drilling holes with both large and small diameters.

5. Drills for drilling hollow parts... They have a small cutting part.

6. A device for drilling holes in hard alloys. They have an angle of sharpening of the cutting part of 135 ° and a shank in the form of a cone.

Extra long drills can be divided into several separate groups depending on the structure of the working parts.

• Pen drills for metal stand out... Such models are used for drilling deep holes of large diameter. They are equipped with centering sharpened tips. They also look like a small flat shoulder blade.

• Core drills are of particular importance... These models can also be suitable for creating large diameter holes (it can be up to 150 mm). They are used to work on milling, drilling machines. The devices first cut out the contour of the future hole, and then they make the recess itself on the surface.

• There are models with a cone-shaped working part... These attachments are used for drilling non-ferrous metals or steel. But they process metal sheets of small thickness, which should be less than 10 mm. They can be made as standard, or they can have a stepped design. The latter facilitate further processing of the metal.

Models with a tapered tip allow you to make indentations of different diameters. This will not require regular change of the drill in the chuck. These tools are perfectly centered.

The most famous manufacturers of high-quality extra-long attachments are importers from Europe, China and the USA. The most popular ones are listed below.

• Heller - German brand for the production of drilling tools and elements of various types.

• Reiko.

• DeWalt Is an American manufacturer of electrical equipment, special clothing, various tools and accessories.

• Ruko Is a German brand specializing in the production of metal-cutting products.

Similar products from German, Japanese, Swedish and other manufacturers are quite expensive and are mainly suitable for professional use. But on the market there are no less quality brands of drills at an affordable price. For example, the following:

• "Bison".

• Interskol.

• Makita.

• Hilti.

• Metabo.

The following video talks about the types of drills for metal.