The quality of the marking largely depends on the serviceability and correct sharpening marking tool.

Before you begin, you need to study the safety requirements for working on sharpening machines, outlined at the beginning of this chapter.

Center punches(Fig. 13) are sharpened in the following sequence.

1. Put on safety glasses and turn on the electric motor of the sharpening machine.

Rice. 13. Sharpening the punch: a - position of the hands; b - placement of the conical part on the plane of the abrasive wheel

Rice. 14. Checking the sharpening of the center punch according to the template

2. The center punch is taken with the left hand, and right hand- at the end opposite to the one being sharpened.
3. Maintaining the angle of inclination relative to the grinding wheel, apply the center punch with a cone to the rotating circle with light pressure, and evenly rotate the center punch around its axis with the fingers of the right hand. The position of the punch axis relative to the circle should not
change until a regular cone with a sharp apex is formed. The tip of the punch is periodically cooled in water to avoid releasing its working part.

Rice. 15. Sharpening the scriber: a - position of the hands; b - position of the scriber tip on the surface of the abrasive wheel; o - sample of scriber sharpening

4. Checking the correctness of sharpening is carried out using a template (Fig. 14).

Rice. 16. Sharpening compass legs: a - work procedure; b - sample of sharpening compass legs

Scribbler(Fig. 15) are sharpened in the same sequence as the center punch.

Consider the sequence sharpening compass legs(Fig. 16).

1. The compass is taken with the left hand in the middle, below the arc with the locking screw, and with the right hand - by the hinge joint of the two legs (the legs should be in close contact).
2. With light pressure, the compass is brought to the grinding wheel so that the leg of the compass is at a certain angle in relation to the circle, and the end of the first leg is sharpened; then the position of the legs is changed and the end of the second leg is sharpened.

After sharpening on a grinding wheel, the sharp ends of the legs of the compass are polished on a block, while simultaneously removing burrs on the inner planes of the legs and on the side faces of the conical part.

At correct sharpening both ends must have the same length and taper with the apex of the angle at the adjacent plane of contact of the legs (Fig. 16, b).

Chopping various surfaces and cutting of metal: Cutting out grooves and grooves (straight and curved).

Chopping is called metal processing by cutting and percussion instrument, as a result of which excess layers of metal are removed (cut down) or metal intended for further processing and use is cut into pieces. The following operations are performed by chopping: removing excess layers of metal from the surface of workpieces (chopping off castings, welds, cutting end-to-end edges for welding, etc.); removal of hard crust; cutting off edges and burrs on forged and cast workpieces; cutting sheet material into pieces; cutting holes in sheet material, cutting grooves, etc.

Chopping tools Chisel - cutting tool, made of tool steel in the form of a rod of prismatic or oval cross-section. On one side of the chisel there is a cutting part, the edges of which are sharpened at a sharpening angle β.

The sharpening angle varies depending on the material being processed. For cutting cast iron and bronze, the chisel is sharpened at an angle β = 70°, and for steel β = 60°. On the opposite side, the chisel has a striking part (head) in the form of a truncated cone with a rounded end. With this shape of the striking part, the hammer blow will always fall in the center of the rounded end. The cutting and striking parts of the chisel are hardened over a length of 20 mm. Sharpening of the chisel along the cutting edges is done on a sharpener; The value of the sharpening angle is checked using a template or a protractor.

Kreuzmeisel is a kind of narrow chisel with a short (2...15 mm) cutting edge length. The crossmeisel is used for cutting rectangular grooves, grooves, and also acts as a chisel in hard to reach places. The length of the cutting edge of the crossmeisel is slightly greater than the thickness of the working part that follows it. This prevents the crosspiece from jamming when cutting deep grooves.

When chopping, the hammer can be used with a round or square head. Round-faced hammers provide greater impact force and accuracy than square-faced hammers. The weight of the hammer when chopping is selected based on the length of the cutting edge. One millimeter of the cutting edge of the chisel should account for 40 g of hammer weight, and for a cross-cutting machine 80 g. The average weight of hammers used in chopping is 600 g.

Fig. 17. Tool for chopping: a) chisel, b) crossmeisel.

Metal cutting techniques

Metal cutting is done in a vice, on a plate or anvil. Bulky parts are processed at their location. Working with a chisel manually requires following the basic cutting rules and appropriate training.

Cutting metal. When cutting metal, the chisel is set vertically and the cutting is carried out with a shoulder blow. Sheet metal up to 2 mm thick is cut with one blow, so a lining of mild steel. Sheet metal with a thickness of more than 2 mm or strip material is cut to approximately half the thickness on both sides, and then broken, bending it alternately in one direction and the other, or beaten.

Figure 18. Cutting a strip on an anvil.

Figure 19. Beginning (a) and end (b) of installing the chisel when cutting sheet metal and notching along the contour.

Cutting blanks from sheet metal. After marking the contour of the part to be manufactured, the workpiece is placed on the plate and cutting is carried out (not along the marking line, but 2...3 mm away from it - filing allowance) in the following sequence:

• install the chisel obliquely so that the blade is directed along the marking line;
• the chisel is given a vertical position and light blows are applied with a hammer, cutting along the contour;
• they chop along the contour, delivering strong blows to the chisel; when moving the chisel, part of the blade is left in the cut groove, and the chisel is again moved from an inclined position to a vertical position and the next blow is applied; This is done continuously until the end (closure) of the marking line;
• turning the sheet over, they cut through the metal along the contour clearly marked on the opposite side;
• turn the sheet over again and finish cutting;
• if the sheet is relatively thin and sufficiently cut, the workpiece is knocked out with a hammer.

Figure 20. Cutting out a workpiece from sheet metal: a - cutting through the workpiece along the contour, b - knocking out the workpiece with a hammer.

When cutting with a chisel with a rounded blade, a smooth groove is formed, and when cutting with a chisel with a straight blade, a stepped groove is formed.

Cutting sheets and strip metal performed in a vice. Sheet material is usually cut at the level of the vise jaws. The workpiece (product) is firmly clamped in a vice so that the marking line coincides with the level of the jaws. The chisel is installed to the edge of the workpiece so that the cutting edge lies on the surface of two jaws, and the middle of the cutting edge is in contact with the material to be cut at 2/3 of its length. The angle of inclination of the chisel to the surface being processed should be 30...35º, and in relation to the axis of the vice jaws - 45°. In this case, the chisel blade goes obliquely relative to the jaws of the vice and the chips curl slightly. After removing the first layer of metal, the workpiece is moved above the jaws of the vice by 1.5...2 mm, the next layer is cut off, etc.

Figure 21.1. Chopping sheet metal in a vice: a, b - the inclination of the chisel, respectively, to the surface being processed and to the axis of the jaws.

Felling according to marking marks is the most difficult operation. Scores are first applied to the workpiece at a distance of 1.5...2 mm from one another, and bevels (chamfers) are made at the ends at an angle of 45º, which facilitate the installation of the chisel and prevent chipping of the edge when cutting fragile materials. The workpiece is clamped in a vice so that the marking marks are visible. They cut strictly according to marking marks. The first blow is applied with the chisel in a horizontal position, further cutting is carried out when the chisel is tilted by 25...30º. The thickness of the last finishing layer should be no more than 0.5...0.7 mm.

Figure 21.2. Felling according to marking marks.

Chopping wide surfaces is a labor-intensive and low-productivity operation used when it is impossible to remove a layer of metal on a planing or milling machine. The work is carried out in three steps. First, a little metal is cut off at two opposite ends of the workpiece, making chamfers (bevels) at an angle of 30...45°, and marks are applied at two opposite side ends, marking the depth of each working stroke. Then on wide surface the workpieces are made with parallel marks, the distance between which is equal to the width of the cutting edge of the crosspiece, and the workpiece is clamped in a vice. After this, narrow grooves are first cut with the crossmeisel (Fig. 15), and then the protrusions remaining between the grooves are cut off with a chisel. After cutting down the protrusions, final processing is performed. This method (pre-cutting grooves on wide parts) greatly facilitates and speeds up cutting. On workpieces made of cast iron, bronze and other brittle metals, in order to avoid chipping of the edges, chamfers are made at a distance of 0.5 mm from the marking line.

At cutting of non-ferrous alloys It is recommended to slightly moisten the cutting part of the chisel with soapy water or wipe it with an oiled rag, and when cutting aluminum - with turpentine. This helps to increase the durability of the cutting part of the chisel until the next resharpening.

Chopping in a vice. In a vice, small workpieces are cut from sheet and strip metal. While working, the worker should stand half a turn to the vice, with his left leg forward and his right leg slightly back. The feet are positioned at approximately an angle of 40...45 degrees relative to each other. The workpieces are strengthened in a vice so that the marking mark coincides with the surface of the vise jaw strips. When chopping, the chisel is held in the left hand and the hammer in the right. The chisel is grasped with the fingers of the left hand by its middle part at a distance of 20...25 mm from the head and set relative to the surface being processed at an angle of 30...35 degrees. vertical plane and 45 degrees in the horizontal plane. The contact of the chisel with the metal being processed should be in the middle of the cutting edge; the non-working areas of the cutting edge of the chisel must move along the surface of the steel bars of the jaws of the vice. Depending on the size of the chips being cut, the force of the hammer should be different. When removing small layers of metal, when a small impact force is required, a “wrist” blow is used, i.e. Only the hand is involved in the work. The “elbow” blow, carried out by moving the hand in the forearm, is used as a stronger blow when removing medium-sized chips. The most powerful is considered to be the “shoulder” blow, in which the hand is involved along with the forearm and shoulder.

Rice. 22. Body position when chopping in a vice.

When chopping, you need to look at the cutting part of the chisel and the marking mark on the workpiece, and not at the head of the chisel. This makes it possible to control the position of the tool during chopping and monitor the size of the metal layer being removed. Strikes must be applied evenly

Rice. 23. Position of the workpiece, hammer and chisel when chopping in a vice. Wide surfaces are chopped in two steps. First, straight grooves are cut on the surface at a distance of 3/4 of the length of the chisel blade using a cross-cut tool, and then the remaining protrusions are cut off with a chisel.

Rice. 24. An example of cutting grooves on a slab using a crossbar.

Chopping on a stove. Cutting and cutting out workpieces on a plate, anvil or rail is carried out in cases where it is not possible to clamp and process sheet metal in a vice. Before cutting begins, the workpieces are first marked with marking marks that determine where the metal is divided into parts. The workpiece is placed on the plate. The chisel is installed vertically with a slight tilt in the direction opposite to the movement. Applying light blows to the chisel with a hammer, it is carefully moved along the marking line. Using this technique, the workpiece is cut. Then the chisel is set strictly in a vertical position and with stronger blows, moving along the cut groove, the workpiece is cut. The workpiece is usually not completely cut; then it is broken by bending it manually or in a vice with a hammer.

When cutting round blanks (made of rod material), they are cut in a circle along the marking line, and then broken off.

To cut out a workpiece from sheet material, first mark the outline of the part. The sheet is laid on the plate, after which the workpiece is cut out along the contour at a distance of 1...2 mm from the marking line. In this case, the contour is cut with light blows of the hammer, and then with strong blows on the chisel, the workpiece is cut out in several passes. Before the last pass, the sheet is turned over and the final cutting is performed. Sharpening of chisels and crosspieces is carried out on sharpening (sharpening) machines (Fig. 25, a). To sharpen tools made of tool steels (carbon, alloy and high-speed), use a grinding wheel made of electrocorundum with a grain size of 40, 50 or 63 on a ceramic bond (PP 15A, 50N SM2 5 K5 A).

PP – flat-rectangular circle shape

15A – electrocorundum

50N – wheel grit is normal

CM2 – degree of hardness

5 – circle structure

K5 – circle bundle, ceramic

A – circle class.

The sharpening angle is checked with a template, which has corner cuts of 70, 60, 45 and 35 o (Fig. 25, b, c). After sharpening, the burrs are removed with a fine-grained abrasive stone (the blade is threaded).

Scribblers (needles) are used for drawing lines (scores) on the marked surface using a ruler, square or template. Scribblers are made from tool steel U10 or U12. To mark on a steel, well-treated surface, brass scribers are used, and on aluminum, marks are applied with a sharply sharpened pencil.

Three types of scribers are widely used: round, with a bent end and with an insert needle.

A round scriber is a steel rod 150 - 200 mm long and 4 - 5 mm in diameter, one end of which is hardened to a length of 20 - 30 mm and sharpened at an angle of 15°, and the other is bent into a ring with a diameter of 25 - 30 mm (Fig. 32, A).

A scriber with a bent end is a steel rod, sharpened on both sides, one end of which is bent at an angle of 90° (Fig. 32, b). The middle part of the scriber is thickened and knurled for convenience. Using the bent end, marks are applied in hard-to-reach places (Figure 32, c).

The scriber with an insert needle (Fig. 32,d) is made like a clock screwdriver; sharpened and hardened steel rods can be used as an insertion needle.

Pocket marker scriber

V. A. Andreeva (Fig. 32, l) is made in the form of a pencil with a retractable tip. The body of the scriber consists of two parts, rotating relative to each other on four balls, which are wound through longitudinal grooves during assembly. A holder is provided to secure the scriber in the worker’s pocket and to prevent it from rolling off the stove. A rod made of VK6 hard alloy, sharpened to a cone with an angle of 20°, is soldered onto the working rod. The scribers must be sharp. Conical surface The scriber should be well processed (smooth), not scratch the ruler or square. The sharper the working part of the scriber, the thinner the marking mark will be and, therefore, the higher the marking accuracy. The scribers are sharpened on sharpening machines (Fig. 33). The scriber is taken by the middle with the left hand, and with the right hand by the end opposite to the one being sharpened. Maintaining a constant angle of inclination relative to the abrasive wheel, with light pressure apply the scriber with a cone to the rotating circle, evenly rotating it with the fingers of the right hand. To avoid tempering, the scriber tip is periodically cooled in liquid.

Punch-fitter a tool used for making indentations (cores) on pre-marked lines. Cores are made so that the marks are clearly visible and are not erased during the processing of the part. Cores are made from tool carbon steel U7A, U8A, 7ХФ, 8ХФ. The working part of the punches (cone) is thermally treated over a length of 15 - 30 mm to a hardness of HRC 55 - 59, and the impact part - over a length of 15 - 25 mm to a hardness of HRC 40 - 45. The middle part of the punch is knurled (knurled) for ease of use .

Punch punches can be ordinary, special, spring (mechanical) and electric.

An ordinary punch (Fig. 34, a) is a steel rod with a length of 100, 125 and 160 mm and a diameter of 8, 10, 12 mm, its striker has a spherical surface. The point of the punch is sharpened on a grinding wheel at an angle of 60° (Fig. 3A, 6). For more precise markings, small punches with a tip sharpened at an angle of 30-45° are used.

Rice. 38. Punchers: a - pneumatic “gun”, b - pneumatic portable A. N. Podvysotsky

For center punches, to mark the centers of holes to be drilled, the tip is sharpened at an angle of 75°.

High-performance punches are special, for step marking, spring, and electric.

Special punches(Fig. 35,a) are used for punching small holes and rounding small radii. The use of such a center punch significantly improves marking quality and productivity.

Center punch for step marking(Fig. 35.6) consists of two core punches - the main 7" and the auxiliary 2, fastened with a common bar 3. The distance between them is adjusted using holes in the bar 3 depending on the pitch of the holes being marked. The first recess is punched with a center punch 7. Then into the resulting punch 2 is inserted into the recess and the recess is punched with a hammer on punch 7. After this, punch 2 is moved to the next position. The pitch between the holes is maintained automatically, which ensures accurate marking and increased productivity.

A punch with a magnifying glass by S. M. Nenastev (Fig. 35, c) consists of two clamps connected by a screw 6 and tightened after installing a magnifying glass 8 according to the worker’s vision. A 3-5x magnifying glass is installed in one clamp 7, the other clamp 5 is used to install the magnifying glass on the center punch 4 at the height of its mounting.

Spring center punch(Fig. 36) is used for precise marking of thin and critical products. The principle of its operation is based on the compression and instant release of a spring.

The punch has a body screwed together from three parts 3, 5, 6. The body contains two springs 7, 7 7, a rod 2 with a punch 7, a striker B with a shifting block 10 and a flat spring 4. When pressing on the product with the tip of the punch, the inner end of the rod 2 rests on the cracker, as a result of which the striker moves upward and compresses the spring 7. Having rested against the edge of the shoulder 9, the cracker moves to the side and its edge comes off the rod 2. At this moment, the striker, under the influence of the force of the compressed spring 7, strikes the end of the rod with the center punch hit. Immediately after this, spring 7 7 restores the initial position of the center punch. The impact force of 10-15 kgf is regulated by screwing or unscrewing the thrust cap 6. Instead of the punch 7, a stamp can be inserted into the rod 2 and then the mechanical punch can be used for branding parts.

Electric punch(Fig. 37) consists of a body 6, springs 2 and 5, striker 3, coil 4, punch 7. When pressed with the tip of the punch mounted on the mark electrical circuit closes and the current passing through the coil creates a magnetic field, the striker is instantly drawn into the coil and strikes the punch rod. During the transfer of the punch to another point, spring 5 opens the circuit, and spring 2 returns the hammer to its original position. The electric punch has high performance.

Air gun"(Fig. 38, a) is used for various core work. For convenience, it is equipped with a handle 7, located at an angle to the axis of the body, and a start button 2.

Pneumatic Portable Punch A. N. Podvysotsky (Fig. 38.6) differs from other punches in its small size and the absence of a handle, which is used by the punch itself.

Compasses used for marking circles and arcs, for dividing segments, circles and for geometric constructions. Compasses are also used to transfer dimensions from measuring rulers for detail.

Marking compasses are: simple or with an arc, precise (Fig. 39,a) and spring (Fig. 39,6). A simple compass consists of two hinged legs (Fig. 39, a), whole or with insert needles (Fig. 39, a), it allows installation the required solution fix the legs with a screw.

Innovative mechanics, trying to improve the accuracy of markings, are improving the designs of compasses.

L. S. Novikov developed the design of a compass (Fig. 39, d), consisting of two legs 6, equipped at the ends with hardened needles 4, and two detachable lenses 7 with fivefold magnification. The lenses are installed so that the ends of the needles 4 are in focus. This makes it possible to clearly see the tip of the needle and accurately align it with the divisions of the scale bar or with the marks of the part being marked.

To accurately set dimensions, the compass has a micrometric screw 2. The advantages of this compass: convenience and high accuracy installations. However, its parts require especially careful handling and storage.

A special feature of the design of the compass (Fig. 39, a) is device 3 for installing the compass directly on its scale with an accuracy of 0.2 mm. The 7 and 2 micrometer screws increase the accuracy of this installation. Replaceable needles 4 are tightened with nuts 5.

The marking caliper (Fig. 40,a) is designed for precise marking of straight lines (Fig. 40,6) and centers (Fig. 40,a).

Marking caliper(Fig. 41) is used for marking circles of large diameters. It has a rod 3 with millimeter divisions and two legs - fixed 2 with a locking screw 7 and movable 8 with a frame 5 and a vernier 6, a locking screw 4 for securing the frame 5. The locking screw 7 is used to secure the insertion needle 9, which moves down and up and can be installed at different levels.

In Fig. Figure 42 shows an improved marking caliper for marking planes. It has a rod 9 with a thickened end into which a cutter 2 is installed. A frame 6 with a vernier 3 moves along the rod. At the bottom of the frame there is an insert 13, into the hole of which a replaceable centering conical support is inserted, secured with a clamp 12.

Frame 6 is connected to clamp 8 using a micrometric screw 7 7. Frame 6 is moved along the rod manually and secured with clamp 4. Micrometric feed of the frame is carried out by turning nut 10 with the clamp secured by screw 7.

When marking, first install a centering support corresponding to the base hole, then install a cutter on the plane of the part to be marked. After this, check the horizontal position of the caliper at level 5, secure the cutter with a locking clamp 7 and make the marking.

Reismas is the main tool for spatial marking. It is used for applying parallel, vertical and horizontal lines, as well as to check the installation of parts on the plate. Reismas consists of a cast iron base 2 (Fig. 43, a), vertical stand(tripod) 5, a screw with a nut 6 for fastening the scriber 4, a set screw 3 for setting the needle for precise adjustment of the size, a bar 7 and a coupling 7. The use of a surface gauge is shown in Fig. 43.6.

For more accurate markings, a surface gauge with a micrometric screw is used.

Gauge gauges for marking are described in Chapter XIX "Basics of measurement".

Any cutting tool becomes dull during use, and therefore needs to be sharpened from time to time. This operation is best and easiest to carry out on a sharpening machine or other mechanical sharpener.

Sharpening chisels and crosspieces. Taking the chisel in your hands, carefully apply it to the rotating circle and move it left and right with light pressure. Both faces are sharpened alternately. The angle between them - the sharpening angle - can be different and varies depending on the hardness of the material being processed within the following limits: for aluminum and zinc - 35°, copper and brass - 45°, steel - 60°, cast iron and bronze - 75°. It is most convenient to check sharpening angles using a template.

The rules for sharpening a crosspiece are the same as for a chisel.

Sharpening drills. The picture below shows the front of a twist drill.

Helical grooves along the axis of the drill are used to remove chips. The rib between the groove plane and the flank surface is cutting edge. The angle between the edges is usually 116-118°, but it can vary, depending on the hardness of the material being processed, from 90 to 140°. When sharpening, hold the drill with your left hand, perhaps closer to the front, and hold the shank with your right hand, rocking the drill smoothly.

In this case, the following conditions must be observed: a) the cutting edges must be symmetrical, have the same angle of inclination and the same length; b) the transverse edge must make an angle of 55° with the cutting edge. Correct sharpening is checked using a template.

The sharpening of the punch is similar sharpening drills. The tool is held with the left hand, pressing it against the abrasive wheel, and with the right hand it is evenly rotated to obtain an even cone. The sharpening angle is 60°, for marking centers - 120°.

Remember that you cannot press hard on the tool while sharpening, otherwise its working end will heat up too much and may come loose and lose its hardening. During operation, hot particles are released from the tool and the abrasive wheel, which can get into your eyes. When sharpening, use safety glasses or a protective shield!

If the metal is sufficiently hard, a drill or self-tapping screw screwed in with a screwdriver can easily slide off the intended point, and in such a situation a large scratch or even a broken drill cannot be avoided. To prevent this from happening, it is customary to make holes or cores, and there is a special tool for this - a center punch!

Penciler - what kind of tool?

The capper is a completely simple device - a steel rod from 100 to 160 mm in length, with a diameter of 8-12 mm. The rod is at the same time a handle, so it has multiple notches to prevent it from slipping out of the hand. The tip of the tool is usually made of special hard alloys and sharpened at an angle from 30° to 75°, depending on the purposes being pursued. The sharper the angle, the more accurate the markings are made, right down to marking the center of future holes.

For example, a core from a tool with an angle of 45° is convenient for further centering of arcs or circles, and a hole from a core with a 90° sharpening allows the drill to hold tightly to the surface. Using this tool is completely simple - first, make a mark on the surface with a pencil, then apply a marking tool to the drawn line in your left hand (if you are right-handed), press firmly and hit the end with a hammer in your right hand.

Just don’t confuse a punch with a punch! Of course, if necessary, it is also possible to punch a hole for a nail or screw in thin metal; moreover, if the tool is well sharpened, this can happen completely by accident if you do not calculate a little force. However, the core of the piercer will very quickly become dull from such use or, even worse, break.

However, this part of the tool is replaceable, so when purchasing it, do not forget to purchase a couple of such consumables.

The compass marker allows you to easily mark arcs of small diameter, and the bell marker serves for more accurate marking of central holes on workpieces that are subsequently subject to additional processing. The principle of operation of these tools is extremely simple - apply it to the product or workpiece, hit the end with a hammer and get the desired core.

Mechanical spring punch - a tool for working without a hammer

If you need both hands to work with a conventional puncher, then to work with a mechanical or spring tool you only need one hand. The principle of operation of such a tool is to tightly compress and independently release a spring, which activates the internal striker, which strikes the rod.

There is also an electric automatic punch, in which, instead of the effort of a human hand, the striker is activated by an electrical circuit that creates a short-term magnetic field. The firing pin is retracted under the influence of the field, the chain is opened, and the released firing pin strikes the rod. Mechanical and electrical punchers are ways to speed up the punching process significantly– you can make up to 40-50 holes per minute!

However, such time savings are unlikely to be relevant if you purchase the tool for household needs - this means that you will take it out of the case no more than once a year. The best option For home use there will be either a standard capper or an inexpensive spring version, for permanent job It’s better to purchase, at a minimum, a high-quality mechanical core, and even better, its electric version.

Do-it-yourself capper - what can you make it from?

The capper can be made from a thin drill, sharpened under the right angle. However, the thin rod is very unstable and every now and then it will jump out from the impact and fly into different sides. Therefore, either think about the option of a good handle, or purchase a ready-made tool. By the way, with ready-made tools, not everything is so simple - the rods often become dull very quickly, after the first 50-100 punches. This is explained simply - the manufacturers used a cheap alloy.

In this case, you cannot do without your own creativity! Again, an old drill bit or carbide drill bit will come in handy. Your task is to fit one end to the drill chuck or. To do this, you may need to cut off excess parts with a grinder or sharpen them with a sharpener. When the job is done, insert the rod into the chuck and turn on the tool at 500-1000 rpm. In this mode, bring the rod at the desired angle to the sharpener and sharpen until you get the desired point. Then you cut off the excess length from the rod and adapt it to the core. It may take you about half an hour to do everything.

Close relatives of the piercer are the doboynik and the bolt

The cap, the beard-doboynik and the bolt are so similar in appearance that it’s easy to confuse them! However, they all perform completely different functions. The beard-finisher has almost complete similarities with the puncher, with the difference that its working part is a trimmed cone. A hammer can also leave large marks on metal, but most often it is used to punch small holes in metal or to drive fasteners into the material.

Finishers are most often made of chrome-vanadium steel. It is better to choose a tool with a hardened tip and striker. The handle should be thick enough to be comfortable to grip with your hand. Be sure to purchase a tool with notches to make it easier to hold it in your palm when striking. The bolt also differs from the nailer by a tip in the form of a tube, at the end of which teeth from durable metal. A bolt is used to punch holes in brick and concrete walls.

Or rather, they used it... Now that it is faster and easier to make a hole with a hammer drill, builders will not bother working with a bolt. However, the tool will come in handy for household needs - it’s more difficult not to buy for the sake of a few holes a year, and the price is higher. The convenience of the tool lies in the fact that when working, crumbs collect inside the tube, which needs to be removed and shaken out from time to time. When there is no bolt at hand, a hole can be made with a regular drill, preferably old, whom you no longer feel sorry for. Tapping the drill, gradually turn it along its axis, remove it from time to time and blow out the hole.

Another close relative of all of these tools is the awl-punch. It is distinguished from an ordinary awl by its cap or handle, which is adapted to be struck with a hammer. This tool will be useful to anyone who works with leather or thin sheets metal Using a punch, small holes can be easily punched.

We must not forget about the metalworker's chisel - a metal rod that is used to chop metal or is used in finishing works, if you need to break off a small piece of concrete. The chisel is made of hardened steel, one end of the rod is slightly rounded for ease of hammering, the second edge, which is also called the “shank,” is flattened and sharpened. Often, for the safety of the hand holding the chisel, a plastic attachment with a cap is put on the striking side.