Each master must have among its many instruments is the drill. With it you can make holes in any material, such as wood or metal. There are many different types of drill bits used for a particular work. One of these is the stepped drill bit for metal. It’s kind of a novelty in the domestic market. Many people have no idea what it is, how and where it can be applied.
This is a drill attachment for drill or drill press. Its purpose is to drill through-holes in the sheet metal. It is recommended to use in cases of need for accurate drilling, and receipt of large diameter.
Snap-in includes the following components:
— working part having a stage, representing the cutting edges. The transitions of the steps are chamfered, which gives the ability to remove burrs in drilled hole. The end of the head is a sharpened peak;
— shank, by which the snap-fastened in the Chuck. This part is hexagonal or round. The most practical recognized round shanks, since they are more reliably and simply mounted in the Chuck of a drill or a screwdriver that does not allow for rotation during drilling. This is very important if you require a large cross-section of the hole.
it is Better to buy drills, the shanks of which are flats. They are necessary in order to prevent slipping of the Chuck jaws. But if the surface is smooth, you might slip and fail to transmit the required torque.
it is also Advisable to choose the accessories which are made from high speed steel because this material is considered ideal for the processing of metal products.
the Step drill is significantly different from other in appearance, as the shank has the shape of a cone. There are different production versions of this part, for example, metric, tool, long, Morse taper, but the most common one is of the instrumental type. Such a cone is considered the most best for installation on heavy equipment, where there is an automatic change of tools.
Important technical characteristics are as follows:
— the number of steps. There are nozzles that have only 3 to 6 stages, and those stages which reach 10 levels. This ensures the versatility of the drill to use, you can make holes of different sizes. Snap has up to 15 stages.
, is the size of the individual stage;
— step, i.e. the distance between the stages;
— drilling diameter, measured in millimeters. It depends on what size is the working part and how many steps.
the advantages of the drill:
— precise drilling. Maybe a quiet hole without fear that the shift to the center. Even easy to fix a sloppy hole, which happened from the use of conventional helical drills, using speed;
— universal use. With this tool it is possible to drill holes of various sizes;
— simultaneous chamfering. You can work with immediately carefully remove the chamfer. There is no need to change tooling if required a hole of different diameter.
— the passage is not deep enough, because it is limited by the height of the step;
— you have to use a tool with a small rotational speed and relatively high torque;
— there is a strong sensitivity to distortions, the appearance of which is possible when drilling;
— the value of the instrument is quite high.
to Pick up a stepped drill in order to perform a specific job will not be difficult, because today produce a variety of types:
— to work with materials that are difficult to handle;
— punching holes in the parts, which are manufactured from light alloy;
— to work with the special plates of solid alloy, which improve the cutting characteristics of the drill.
there are Also the following types of step drills:
1. size: large, medium and small;
2. configuration: straight and spiral grooves. The quality of drilling they do not differ. The only difference in ease of sharpening, twist to sharpen much more difficult. For sharpening drill straight enough to use a rotating emery paper, conducting it along the groove. This can be done by using a drill or grinder with a special attachment. Of course, the possibility of manual sharpening;
3. type deposition: cobalt and titanium. Titanium think better and more reliable.
Especially step drills are widely used in workshops. They are very convenient for drilling the car body or frame of the motorcycle.
the Principle of operation of the drill lies in the fact that the nozzle is fixed in the tool, sharpened the top next to the workpiece and starts drilling. First, it performs the first cutting edges, then removed the burrs and then expands the hole to the desired size. It is very important to stop the snap when the auger reaches the desired diameter.
Drill speed – tools are quite fragile. When working it is necessary to keep perpendicular to the metal sheet, to prevent distortion. It is important to remember that the larger the drilling diameter, the lower the rpm of the drill. Importantly, in the process, not much pressure, to prevent overheating of the drill.
in order to work with a drill to capture the required diameter, you can pre-mark the hole.
of Course, it is necessary to use coolants. If special tools are not available, you can use liquid soap or lubricating oil. Lubrication is a very important tool, as it increases its service life.
are Very similar with the step drill, conical drill. It is most easy to drill, holes are conical and not cylindrical, as after work with the step drill.
the Drill speed in metal is undoubtedly an effective tool for working with the material, which provides fast, accurate drilling of a hole of the desired size. Therefore, this type of drill will be indispensable assistant every master. The main thing to take seriously the choice of such a drill bit, then drill the process< / span>tion will bring maximum joy, thanks to the excellent quality and ease of drilling.