All About Step Drills

From time to time, we are all faced with the need for minor repairs. This can be gluing a strip of wallpaper that has come off, nailing a skirting board that has come off the wall, or drilling holes in the wall or floor. Someone uses the services of repairmen, but many men prefer to do such work on their own. Of course, this requires an appropriate arsenal of tools.

Step drill differs in its configuration from other types of drills. It has both a stepped and a conical shape at the same time. Thanks to this design, there is a difference in diameters on the drill body - its own at each of the steps. This type of drill is used for drilling holes with different diameters. Everything will depend on which stage is used for drilling. Any stepped drill is manufactured and operated in accordance with GOST 28320-89, which is interstate. If we talk about the advantages over other types of drills, then, first of all, the cone drill with "steps" is used to drill perfectly even holes in thin sheets (when it comes to metal).

A conventional drill does not allow achieving such an effect, since it is screwed into a thin sheet like a self-tapping screw. Accordingly, notches are observed in the hole, and it itself has a non-ideal diameter. This is not a problem unless you need to drill a straight hole without notches or serifs. If you need a perfectly even circle, then you cannot do without a stepped drill. In addition to all of the above, after working with such a drill, additional processing of the edges of the hole with a file or sandpaper is not required.

Conical drills are irreplaceable and, if necessary, drilling holes with a large diameter - from 2 cm. Since the lower "steps" of such drills can have a diameter of more than 3 cm, it is they who contribute to the formation of correct and even holes with a large diameter. It is also important that this type of drill is perfectly "mounted" with an ordinary household electric drill. Tapered "step" drills will last a very long time, since only high-strength alloys are used for their manufacture.

Drill body covers titanium nitride, thanks to which the possibility of stitching the product is completely excluded. Minus This type of drills is directly related to the materials for their manufacture - the price for them is consistently high. For comparison, ordinary drills can cost up to 50 rubles, while for one step you will have to pay a thousand rubles, and this is the minimum! If you purchase products from a well-known manufacturer, then the cost can be 2,000 rubles or more.

The design of the product provides for two main parts: a working part (the so-called body with a tip) and a shank. Since the body is tapered, the tip is pointed. This eliminates the need for centering devices and can handle even the toughest material.Neither a file nor a sander is required to bring the hole to a perfectly flat shape, a drill itself works very cleanly. Steps of stairs products may vary, their size depends on the type of tool.

If the size of the hole that the drill can make is less than 1.2 cm, then the step is 1 mm. If more than 1.2 cm, then the step is also larger and is already 2 mm. Most often, products are found with a pitch of 5 mm.

Shank called the part with which the product is fixed in the chuck of the electric drill. Depending on what kind of drive mechanism the product has, the shank can be cylindrical, triangular or hexagonal. Trihedrons or hexagons create an obstacle to turning the drill during the operation of the electric drill.

Taper products and step drills are different from each other - the working part has either a smooth surface or a ribbed surface in the form of steps. Tapered gimbal represents step-by-step annular transitions along which a longitudinal groove in the form of a spiral with cutting edges passes. If you use such a product, then the finished hole cannot be adjusted manually - only on a special machine. Combination drills are designed to form through holes and to cut holes in thin sheets of metal.

Herringbone step drills differ in diameter - it can be as minimumand maximum... The diameter can be up to 58 mm.

Step drills are made from become, however, steel can be very different: from brittle, unhardened, to super-strong alloys. Its functions depend on how strong and hardened steel is used for the production of the gimbal.

The shape that the shank has is also important. The shank can be round, triangular or hexagonal.

According to this criterion, drills are also divided into several groups: two-stage and multi-stage. The more steps, the wider the range of actions that the user can perform with the gimbal. As for the two-stage drills, this is a special a category of tools equipped with a countersink directly in the shape of the screw head.

What kind of protective coating is applied to the product can be easily identified by its color. Gray means there is no coverage. Black - the steel is hardened. Gold or silver indicates that the product has high strength, as well as that it is sprayed or abrasive.

There are drills for metal (thin-leaf and thick-leafed), wood, plastic, glass. For the manufacture of any of them steel is used, however thickness, configuration and appearance may vary.

The peculiarity of the device under discussion is the number of cutting edges it has. The number of edges is not related to the number of steps that the drill has, since the cutting elements are located in the grooves of the tapered part. Also, the function of the grooves is to deflect the swarf generated during operation.

All existing grooves can be divided into 3 main types: longitudinal, rectilinear, spiral. Each design has its own advantages. If we talk about a straight edge, then it is easier to sharpen and straighten. The spiral flute drills run smoothly and smoothly. They are very often used for drilling thin-walled materials.

In a stepped drill, the diameter ranges from 4-80 mm, and the length is 58-85 mm.Shanks can also have different diameters - 6-12 mm. The stronger the steel used to make it, the stronger the tool will be. If the drill is gray, then this means that the steel was not hardened, if it is black, then the steel has been treated with steam, which means that it is much stronger and more durable. Products with a golden hue are even higher quality, and the strongest and most wear-resistant drills are titanium-coated or diamond-coated.

Each product is applied special marking, by which you can find out from what material (including the brand) it is made, the diameters that it has, the step step. Also, the marking contains information about the hardness and diameter of each step. For example, HRC means that high quality high speed steel was used to make the drill.

When deciding which model to buy from which manufacturer, you should pay attention to the following: examine the characteristics of the drill... Some products work well with metal, while others work worse.

It is imperative to study the material from which the product was made. It is gray, black or golden. It depends on what kind of application the gimbal is subject to in practice. Products that are gray, have low strength, they are fragile. Therefore, these drills are not suitable for working with high-strength materials. If you need to drill through very tough materials, a cobalt alloyed steel is perfect for drilling. True, it should be borne in mind that such drills are very expensive, but on the other hand, you can process very durable surfaces at high speeds. It is important to consider the information contained in the labeling... A reputable manufacturer will add reliability to the product.

To drill holes with a large diameter, experts advise to reduce the speed of rotation of the tool as the process nears completion.... If this is not done, there is a high risk of increasing the diameter of the hole, chamfering with the tapered part. The general rule is that the larger the diameter of the planned hole, the lower the rotational speed of the drill should be. The part should be positioned so that there is free space for the gimbal. If the hole is being drilled in a thin material, then something must be placed to ensure a solid and level base. You also need to monitor the temperature of the tool to prevent it from overheating.

Stepped gimbals are suitable both for forming a hole and for correcting it. - they eliminate jagging, make a neat, even circle out of triangular or square holes. If you do everything correctly, the edge of the material will not deform, the edges will not bend, and the paintwork will not peel off.

It is ideal to work with such "complex" materials as sheet metal, plastic, fiberglass and others by means of stepped gimbals. They are widely used by car mechanics, installers and other professionals. If the product can be sharpened, there will be no problems with this. It is easy to sharpen the gimbal both with the machine and with your hands. To secure the drill and work, not only a standard electric drill, but also a screwdriver is suitable.

The following video presents an unboxing, review and test of step drills with Aliexpress.