Device for chiselling eyes in a tree. Tools for chiselling. Chisel cutting techniques

Cutterthat removes shavings during rectilinear mutual movement of the cutter and the material is called planing (with horizontal cutting) or mortising (with vertical).

The nature of the work of planing and grooving cutters is the same. Both when planing and when chiselling, the cutter cuts only during the working stroke. At the same time, at the beginning and end of each stroke, tremors occur that adversely affect the operation of these incisors. Planing tools or mortising tools are representatives of groups: a planing tool or a mortising tool.

Planing tool (planer)

Planing incisor, as a representative of the group - planing toolCompared to turning, it works in more severe conditions, since it always enters the processed material with impact and experiences uneven stress due to changes in cutting forces.

In the process of cutting on longitudinal planing machines, the table, along with the workpieces installed on it, moves along the fixed cutters, so here we have to deal with large inertial masses. This circumstance makes it necessary to apply reduced cutting conditions, especially with regard to speed, not only for high-speed steel cutters, but also for carbide cutters. Planing tool  happens: through passage, cutting, detachable and groove special.

Mortising tool (gear cutting dolbyak)

The cutting cutter working by the break-in method belongs to the group - mortising tool. The dolbyak is a gear wheel meshed with the manufactured one, but at the same time, performing the cutting process as a result of the vertical reciprocating movement obtained by it, similar to a grooving cutter. During the operation of the dolbyak, the gearing of two gears is reproduced. With such a mortising tool, cylindrical gears are cut both with straight and with oblique teeth of the external and internal engagement. According to GSOT they are designed for machining wheels with a profile angle of the initial contour of 20? according to GOST. Usually dolbyak  It is used for cutting wheels with involute engagement, but it can be used for machining parts and with an arbitrary repeating profile.

Dolbyak, as a representative of the group - mortising tool, in accordance with GOST, five types and three accuracy classes are manufactured. The first type includes a spur disc dolbyak. It is made with a nominal pitch diameter of 75, 100, 125, 160 and 200 mm. The second type includes a disk helical dolbyak. It is made with a dividing diameter of 100 mm and a helix angle of 15 and 23 0.

The third type includes a cup spur gear, diameters of 75, 100, 125, 50 mm. The fourth type includes the tailed spur gear with a nominal dividing diameter of 25 and 38 mm. The fifth type includes a tail helical cutter with a diameter of 38 mm and with a helix angle of 15 and 23 0. In addition to the above listed types of mortising tools, there are gear cutting spur gears for splined joints with an involute profile.

Chisels and chisels are used for chiselling nests, stripping edges and trimming planes, spikes, eyes, cutting veneers (Fig. 4.1-4.9). The industry produces bits from 6 to 22 mm with a gradation of 2 mm, and chisels from 6 to 20 mm with a gradation of 2 mm and from 20 to 40 mm with a gradation of 5 mm. Such a set is sufficient for household and construction work, but for carpentry, narrow chisels from 1 to 6 mm with a gradation of 1 mm are still required.

The chisel differs from the chisel in a larger thickness and a handle with a shackle on top, protecting the tree from destruction by a hammer. In carpentry practice, strong blows are not required, since deep nests are usually first drilled and then cleared. Hammering with strokes is inherent in carpentry, thin carpentry parts can also be split. Therefore, it is enough for the joiner to have a set of chisels from 2 to 16 mm and two wide chisels 25 and 40 mm, as well as two chisels 6 and 12 mm.

Fig. 4. Tools for chiselling and drilling:
  1 - bit; 2 - wide forged chisel: a - insertion of the tail into the workpiece of the pin; 3 - narrow chisel; 4 - a semicircular chisel with an external chamfer; 5 - the same, with an internal chamfer; 6 - a flat rezchitsky chisel; 7 - klukarza; 8 - rounded chisel chisel; 9 - a corner chisel; 10 - perk; 11 - rot; 12 - manual screw drill; 13 - spiral drill on wood; 14 - cork drill (head); 15 - spiral drill; 16 - countersink

Narrow chisels are made of spring wire, files, grinding them accordingly on an emery wheel. With the exception of the cutting end, the metal should be “released" by heating in a low flame until yellowness appears on the cleaned surface of the chisel (about 160 ° C). If this is not done, then the chisel will turn out to be fragile, since the file metal is hardened along its entire length.

The pins are mounted on the pins - wooden handles of rectangular cross section with barrel-shaped rounded edges. (Round handles are less convenient.) Handles need to be cleaned and polished or varnished with oil. The nozzle should be parallel to the cutting edge of the tool, this helps accuracy in work. For stubs, they take strong viscous wood - dogwood, beech, twisted birch. To fit precisely, the hole is first drilled, observing the direction of the ribs, to a depth of 112 of the shank, and then burned deep into the hot shank, not fully completed. A chisel driven in this way will sit firmly. Obliquely driven handles are fixed by cutting the excess from the right side. Therefore, the handle blank should be made slightly larger in order to be able to correct it.

Chisels are stamped, punching (thin) and forged (thick). Forged ones are characterized by a special tide - emphasis and slight thinning of the pen to the cutting edge. Stamped - have parallel wide edges and require the installation of a thrust washer so that the handle does not stuff on the shank during impacts.

The quality of the chisel depends on steel and hardening. A sharpened chisel should cut 15 cm of beech or oak timber without blunting. If steel wraps or crumbles, the tool should not be used. Sometimes it is possible to improve the metal with a new hardening. The low cost of the chisels allows you to make a choice until you get the right qualities. As a rule, forged chisels are more reliable.

The length of the chisel is selected based on strength conditions: a very long and thin chisel is easy to break. Usually the length of the cutting part is 10-15 cm. Only for some works, for example, when chiselling notches in planers or jointer planes under the knife, the length of the pen is 20-22 cm. The feather in the broad face should be slightly wider by the end (1-2 mm) . It is difficult to work with wedge-shaped chisels, they get stuck in the nest and make the work sloppy. The angle of sharpening wide chisels 20-25 °, narrow - 15-20 °. In the first case, the bevel width should be 2.5 thicknesses, in the second - 3-3.5 thickness of the chisel at the cutting end.

To select the rounded recesses, semicircular chisels of different radius of curvature are used - from almost flat to semicircular. Sharpen them both externally and internally, depending on the nature of the work ahead. In addition, for simple carvings, chisels with a slanting edge are used, shorter and thinner, as well as semicircular, curved like a scoop, the so-called klukarzy. The industry does not produce this tool; it is made in a cunning, blacksmithing way, from bearing rings, springs or thick springs.

Manual chiselling of wood.For the formation of nests, grooves and eyelets of rectangular cross section in wood parts, chisels are used (GOST 1185-80).

Chiselsdistinguish carpentry (Fig. 32, but)and carpentry (Fig. 32, b)The chisel consists of a blade with a blade at the end and a handle. To avoid splitting the handle from being hit with a hammer, a steel ring is placed on top of it. The handle should be firmly and securely mounted on the shank, there should be no sharp corners or bumps. The canvas of the chisels and handles is coated with a colorless waterproof varnish.

Sockets of a rectangular shape with bits are selected according to the marking, and when hollowing through the nests, marking is applied on both sides of the part (Fig. 33, but),non-through - on the one hand (Fig. 33, b)Prior to chiselling, the part is placed on a table or

AT) d)

Fig. 32. Chisels and chisels:

but- carpentry bits, b- joiner's bits, at- flat chisels, g- semicircular chisels; I- canvas 2 - handle 3 - ring 4 - cap

workbench and firmly fix it. When hollowing through holes, to avoid damage to the table top or workbench, a piece of defective board is placed under the part. The bit must match the width of the slot to be selected. If in several parts it is necessary to select the same nests, they are put in the foot and the nests are selected simultaneously in all details.

Nest chiselling begins as follows: the chisel is installed with a chamfer facing inward, retreating 1 ... 2 mm from the marked risks, and with light blows of a mallet or hammer on the handle they deepen it into the wood (Fig. 33, at)and again hit the handle with a mallet or hammer, and then, shaking it, remove the wood and thus continue chiselling (Fig. 33, d). It is necessary to depart from the marking risks by 1 ... 2 mm so that later this place could be cleaned with a chisel.

In order to increase labor productivity, reduce worker fatigue and comply with safety requirements when chiselling, it is necessary to take the correct position: you need to sit so that the hand in which the mallet or hammer is located passes over both legs.

When hollowing, make sure that the edges of the nests do not wrinkle. To avoid creasing the edges, the tilt of the bit should always be towards the middle of the socket.

When hollowing through nests, wood is first selected on one side, and then, turning the part, on the other.

Fig. 33. Chisel work:

but- selection of a through socket, b- selection of a through hole, at- the position of the bit (initial and final) on the marking of the nest, g- nesting procedure

For cleaning and sampling nests, grooves, spikes, chamfering, flat chisels(Fig. 32, c), and for cleaning rounded spikes and machining concave and convex surfaces - semicircular chisels (Fig. 32, d) (GOST 1184-80). As in chisels, chisel sheets are made of tool steel with heat treatment of the working part, and handles are made of wood of the same species as in chisels. Wooden handles are made of hardwood and must have a metal cap. The cutting edge (blade) must be sharpened sharply. The shape and size of the shoulder should provide sufficient support for the handle. Burt should not have sharp corners. Handles are varnished.

In flat chisels, the canvas is a smooth, even strip ending in a sharp blade. The chisel blade in the work acts like a knife, cutting or dividing wood fibers. When twisting the chisel, hold the handle with your right hand. If possible, move the chisel along the fibers. When cutting with a chisel with the right hand, click on the end face of the handle, and with the left, press the chisel blade to the wood. The fingers of the left hand should not be in front of the chisel. The cut chips should be thin, soft and curled, not chipped.

Semicircular chisels process curved surfaces and hollow out the holes of a curved shape. Point angle of chisels (25 ± 5) °. When working with a chisel, blows with a mallet or hammer are applied strictly in the center. The work of the chisel is shown in Fig. 34.

d) e) e) g)

Fig. 34. Chisel work:

but- stripping of trimmed places, b- transverse trimming, at- trimming along the fibers, g- removing the chamfer, d- chamfering, e- mopping, well- cutting

from under the shoulder

In order to avoid injury during work, the chisel should not be cut in the direction of the supporting hand towards you, on the weight, with the part resting on the chest and when the part is on your knees. Do not leave chisels and chisels with the blade toward you or at the edge of the table or workbench, as you may be injured if the tool falls.

Mechanized chiselling.Rectangular nests, grooves, and others are chosen by the electric hammer. The cutting tool of the electric hammer is a continuous grooving chain, which is a set of links (cutters) pivotally connected.

Manual electric mortarIE-5601A (Fig. 35) has a built-in asynchronous squirrel-cage rotor electric motor, in which a sprocket is mounted on the end of the rotor shaft, which drives the cutting chain, stretched to the guide bar. The depth of chiselling is regulated by a stroke limiter. The chain head moves along the guide columns mounted on the base. The chain is tensioned by movement with a stop screw and a ruler. The head drops when you press the lever device - the handle, and rises automatically with coil springs.

Depending on the size of the selected holes, rulers and chains of the desired size are installed. The width of the groove obtained in one pass is equal to the width of the chain, and the length of the groove is the width of the guide bar plus the double width of the chain. A set of chains and rulers is required to select grooves of different sizes. When you-

when working a series of consecutive sockets to a straight line, a groove of the required length can be formed. The depth of the selected hole is adjusted by a stroke limiter, set to the desired size. When lowering the head, it abuts against the base.

Before starting work, it is necessary to sharpen the chain well, then put it on the sprocket and the line of the electro-skid. The electric hammer is installed so that the circuit is located above the socket, which is chosen. The material or part to be processed is laid on the table and firmly “fixed. It is forbidden to work as an electric plunger if the part is not fixed or is on weight.

Electro-rake IE-5601A:

/ - chain 2 - a guide column with a spring, 3 - shield 4 - electric motor 5 - casing, b - lever device (handle), 7 - screw, 8 - guide ruler, 9 - foundation

After turning on the electric motor by pressing on the lever device (handle), the electric hammer is lowered together with the ruler and the chain stretched on it down. The chain must be lowered smoothly, without jolts, so that it is introduced into the wood gradually. The feed rate of the chain depends on the size of the selected nests, the hardness of the processed wood. When the chain comes out of the socket, it must be ensured that there are no bumps or tears on the edges that result from quick removal of the chain from the socket. The rubbing parts of the electric hammer must be coated with lubricant.

At the end of the work, the chain, sprocket and guide bar are washed in kerosene and lubricated with machine oil.

The electric hammer can be used as a stationary machine by attaching it to the table so that the guide ruler with the chain is perpendicular to the plane of the table, and the plane of the ruler is parallel to the edge of the table.

If during operation the body of the electric rake is very hot, it is necessary to loosen the pressure and unload the electric motor, change the blunt chain or loosen the chain tension. If the chain breaks, it must be tightened. In the case when the chain or the ruler is very hot, you need to adjust the chain tension, eliminate possible distortions of the ruler. If when chiselling small chips are obtained in the form of wood chips, a new chain is installed. If the nest, groove in the process of chiseling are oblique, it is necessary to align and strengthen the ruler that goes to the side.

When working with power tools you need to use safety glasses. The body of the electric hammer must be grounded.

4 Joiner's, carpentry and parquet works

Fig. 36. Drills manual and drilling tools:

but- a feather drill, b- center drill at- screw drill, g- twist drill d- rot, e- a drill well- drill, s- gimlet: / - pressure head, 2 - crankshaft 3 - a pen, 4 - switch ring, 5 - ratchet mechanism, 6 - cartridge, 7 - head, 8 - threaded handle 9 - steel rod, 10 - cartridge 11 - cutter, 12 - center (tip)

Manual drilling of wood.Round (cylindrical) holes for round spikes, pins, bolts are selected with drills, consisting of a shank, a rod, a cutting part and elements for removing chips. For drilling used feather, center, screw, twist drills.

Drill bits(Fig. 36, but)have a grooved shape; they choose holes mainly under the pins. The groove also serves to eject chips. Due to the fact that he cannot completely throw out the chips, in order to avoid overheating, he often has to be removed from the hole. Therefore, the holes are unclean and not accurate enough. Drills have a length of 100 ... 170 mm, a diameter of 3 ... 16 mm with a gradation of 1 ... 2 mm.

Center drills(Fig. 36, b)drill through and shallow holes across the fibers. It is difficult to drill deep holes with these drills due to poor chip ejection. Work with drills only in one direction. The drill is a rod ending at the bottom with a cutting part consisting of a cutter, a blade and a guide center (tip). The diameter of the center drills is 12 ... 50 mm, the length depending on the diameter is 120 ... 150 mm. When working with these drills, you need to press, otherwise they will not be embedded in the wood.

Screw drills(Fig. 36, c) is used for drilling deep holes across the fibers. The end of the drill has a fine screw. When drilling with them, the holes are clean, since the chips are easily removed through the screw channels. The diameter of the drill is 10 ... 50 mm, the length is 40 ... 1100 mm.

Twist drills(Fig. 36, d)depending on the shape of the cutting part, there are conical sharpening (GOST 22057-76) and with a center and cutters (GOST 22053-76). There are grooves in the shaft for chip removal

lines. Drills with a center and a cutter are produced with a diameter of 4 ... 32 mm, and with conical sharpening - with a diameter of 2 ... 6 mm (short series) and 5 ... 10 mm (long series).

The drills are driven by a rotor and a drill.

Kolovorot is used for drilling holes when performing carpentry and formwork, and is also used for wrapping and unscrewing screws for glass and other types of work.

Rattle with a rattle(Fig. 36, e)represents a cranked rod in the middle of which there is a handle for rotation. At one end of the crankshaft there is a chuck for attaching drills, at the other - a pressure head. Kolovorot with a ratchet should rotate to the right and to the left, and the direction of rotation is established by a switch ring. The cams of the chuck should provide reliable fastening of tools. You can wrap bolts, screws with a rotor, for which purpose socket wrenches (square or hexagon), screwdrivers are inserted into the cartridge, respectively. Drills with a shank diameter of up to 10 mm can be mounted in the rotor. To screw the screws into the rotor insert screwdrivers. Kolovorot, consisting of a cranked rod, four-jaw chuck, switch ring, is made of structural steel. All parts of the rotor have a protective galvanic coating.

Holes with a diameter of up to 5 mm are drilled a drill.Drill (Fig. 36, e)it is a screw-threaded rod with a handle on it. At one end of the rod there is a chuck for installing drills, and at the other - a head. The rod, and with it the drill, is rotated by moving up and down the threaded handle.

For drilling deep holes use drill(Fig. 36, g), which is a rod with an eye for the handle located in its upper part, and with a screw drill at the other end (in the lower part).

Shallow holes in hardwood for screws drilled gimlet(Fig. 36, h)having a diameter of 2 ... 10 mm. To prevent wood splitting, the gimlet is periodically removed from the hole and cleaned of chips.

When using drills, holes are selected by marking or pattern. The center of the holes is pre-punctured with an awl. Before starting work, the drill must be sharpened well with a file with a small notch or on a special machine, and then firmly fixed in the chuck of the rotor or drill. Drilling techniques are shown in Fig. 37.

When working, make sure that the axis of rotation of the rotor or drill coincides with the axis of the hole. When drilling vertical holes, the pressure head of the rotor is held with the left hand, and the handle is rotated with the right.

Deep through holes are drilled according to the marking from two