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Metal marking

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Marking

Metal marking

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Marking is the operation of applying marks (lines) to a workpiece (forging, casting, rolled product, etc.) for its subsequent processing. Risks can be contour, control and auxiliary.

Contour marks separate the allowance metal from the metal of the finished part. In order for the contour marks to be better highlighted and preserved during transportation and processing of the workpiece, they are punched, that is, small conical depressions (cores) are applied along the marks.

During subsequent processing, the allowance is removed so that half the width of the contour mark and half of each punched recess (core) remain on the part. Contour marks are also used for installation and alignment of workpieces on the machine.

Auxiliary marks serve to measure dimensions when marking and installing a workpiece on the machine.

Control marks are applied next to the contour marks at a distance of 5-10 mm. Being parallel (or concentric) to the contour marks, these marks make it possible at any time to check both the correctness of installation and the correctness of processing (if for some reason the contour mark has disappeared).

Thus, marking consists of drawing on the workpiece the lines necessary for processing the part. Before marking, those parts of the workpieces on which the marks will be applied are painted so that the marks and cores can be easily found. For painting, chalk mixed with glue, diluted in water, is most often used. The treated surfaces of steel and cast iron workpieces are sometimes coated with a solution of copper sulfate in water; this leads (as a result of the reaction of copper sulfate with iron) to the formation of a thin layer of copper on the surface of the workpiece, along which marking marks are applied.

Marking is divided into planar and volumetric. Planar marking is made on sheet material on one side (in one plane); When marking in volume, marks are applied to two (or more) surfaces of the workpiece.

In modern mechanical engineering, they try to avoid marking whenever possible, since it requires highly qualified labor, and the processing accuracy of it is low. However, this is only possible in mass and large-scale production, where markings can be completely or largely eliminated through the use of special machines and devices that ensure correct alignment (installation) of the workpiece and guarantee that the dimensions of the parts are within the established tolerances. In single and small-scale production, the cost of manufacturing devices does not pay off, so parts are processed according to markings. The lack of accuracy of parts processed according to markings forces one to resort to individual fitting during assembly. For marking, the workpieces are placed on marking plates. The upper (working) plane of the slab, on which workpieces and marking tools are installed, and its side edges are precisely processed (planing).

Often, narrow and shallow mutually perpendicular grooves are cut along the upper plane of the slab so that squares with a side of 200 to 500 mm are formed. These grooves in many cases facilitate the installation of workpieces and fixtures on the plate. Slab sizes vary widely from 750 X 750 to 4000 X 6000 mm; larger slabs (for marking very large workpieces) are made up of several slabs and installed on the foundation.

Scale rulers, surface planers, squares, compasses, center punches, etc. are used as marking tools.

A scale bar is used to measure dimensions; it is fixed on the square so that its end (zero line) touches the working surface of the slab.

A thicknesser is used to apply marks to the workpiece parallel to the working plane of the marking plate. When working with a thicknesser, the base is moved along the slab, and with a needle set according to the scale ruler to the height dimension, marks are applied.

A hand needle or scriber is used to mark lines along a ruler, square, or template.

Rice. 1. Scale ruler attached to a square

Rice. 2. Marking thicknesser

Rice. 3. Hand needle (scriber)

Rice. 4. Malka

The square is used to apply vertical marks with a scriber and to check the vertical position of any plane of the workpiece, as well as to construct right angles.

The mark and the goniometer are used to apply groove marks and control the installation of the workpiece on the marking plate. Setting the ruler to the desired angle is done using a protractor or protractor. After installation, the ruler is secured by turning the knob.

A marking compass is used for marking circles and arcs, as well as for marking dimensions taken from a scale ruler. In some cases, a caliper is also used to mark circles and arcs.

A center finder square is used to apply diametric marks on the ends of shafts and, accordingly, find centers at the ends. A center finder square consists of a square and a ruler attached to it, the working edge of which divides the corner of the square in half. To mark, a square is applied to the workpiece and a mark is applied along the ruler using a scriber. To find the center of the workpiece, apply a second mark after turning the square through a certain angle.

Rice. 5. Marking compass

Rice. 6. Square finder

Rice. 7. Kerner

The punch is used for applying core marks on marks or for marking the centers of holes.

Marking

Marking is an operation in which contour lines (marks and recesses) are applied to the part being manufactured (or repaired), defining the boundaries of processing. The marking is called planar when all its lines lie in the same plane, and spatial when the marking lines are drawn in different planes. To carry out marking, you must have a marking plate and a set of special tools and accessories, including: an angle plate (setting square), prisms, measuring squares, a gauge with accessories or an ordinary gauge, i.e. a tripod with a scriber, a caliper with double-sided jaws, caliper with one-sided jaws, measuring ruler, calipers and bore gauge, protractor, marking compass, center punch, screw jacks, scriber, flat, prismatic and wedge-shaped pads, hammer, clamps. For particularly precise marking work, measuring (plane-parallel) end tiles are also used.

Tips for the master

Metal marking is the operation of applying lines (scores) to the workpiece, which, according to the drawing, determine the contours of the part and the places to be processed. Marking can be planar and spatial. Planar marking is used when the contours of the part lie in the same plane; When marking in space, lines are drawn in several planes or on several surfaces. For planar markings, lines are drawn with a scriber (Fig. 117, a), for spatial markings, with a scriber fixed in the thicknesser clamp (Fig. 117, b). Scribblers are made from steel grades U10 and U12, their working ends are hardened and sharpened. The center punch (Fig. 117, c) is designed for making recesses (cores) on pre-marked lines. Cores are made from steel grades U7, U8. The working end of the punch is hardened and sharpened at an angle of 60°. The striking part (the striker) of the tool for centering the blow has a spherical shape and is also hardened. For particularly precise punching, spring and electric punches are used.

Rice. 117. Tools for marking metal: a - scriber; b - scriber fixed in the thicknesser clamp; c - center punch; g - marking compass

The marking compass (Fig. 117, d) is used for drawing circles, dividing angles and applying linear dimensions to the workpiece. Parts are marked according to a drawing, template, sample. When marking according to a drawing, axial lines are first drawn, then horizontal and vertical lines, and lastly, inclined lines, circles and arcs. After this, the contours of the part are marked. Marking according to a template is used in the manufacture of a large number of parts of the same shape and size. Centers at the ends of cylindrical parts are found using center finders and compasses. The centrifuge is a square with a ruler attached to it, which is the bisector of a right angle. The square is placed on the end and a line is drawn with a scriber that will pass through the center of the circle, then the square is turned at an angle of about 90° and a second line is drawn. At the intersection of the lines is the center. A center punch is used for small diameter products. The center is punched by pressing the bell to the end of the product and hitting the head with a hammer. It is often advisable to pre-paint surfaces to be marked so that the marking lines are better visible on them. The following products are used for painting: for untreated surfaces of castings made of ferrous and non-ferrous metals - chalk diluted in water until milky, and 50 g of wood glue per 1 liter of water (the glue is diluted separately, then boiled with chalk); for treated surfaces of steel and cast iron - copper sulfate (2-3 teaspoons per glass of hot water) or rubbing the wetted surface with copper sulfate powder. Non-ferrous and rolled steel, as well as precious metals, are not painted, since the marking lines are clearly visible. In some cases, for a clearer drawing, the marking lines are painted with white watercolor paint. Marking begins with choosing a base, that is, a line or plane from which the dimensions will be plotted. If the workpiece has machined surfaces, they are taken as bases; For symmetrical parts, it is convenient to take the axes of symmetry and center lines as bases. To improve the quality of marking, additional marking of marking lines is carried out at the ends and at intersections with other marking lines. When marking spatially, it is very important to correctly maintain the relative position of the planes on which the marking is carried out. When marking, the scriber is led along the ruler, pressing it tightly against it. In order for the scribe to adjoin the ruler, it is tilted at an angle of 75-80° to the surface to be marked (Fig. 118); in addition, it must be inclined at the same angle in the direction of movement. During the marking process, the inclination of the scriber should not change; the line is drawn only once; If the line is drawn incorrectly, it should be painted over and drawn again.

Rice. 118. Marking metal with a scriber

When drawing circles with a compass, the force must be applied to the leg of the compass that is inserted into the center. If you apply force to the leg that outlines the circle, the compass can easily move and the circle will not turn out.

Tags: Metal, Processing, Marking

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Application

Using a core, you can make marks on any surface. It is advisable to use it when working with smooth materials. These are tiles, polished surfaces. Most often it is used when drilling metal. Therefore, core samples are often referred to as metalworking tools.

Masons also actively use it. Special mason cores have been created for this purpose. They are not much different from locksmiths. They are often powder coated in a bright color to make them easier to find if lost.

Tools for flat marking

Work must be performed on a flat and comfortable surface. Marking tables are used for this purpose:

woody;
iron.

Key conditions for the quality and design of tables:

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Strength and durability. To ensure strength, the table legs are connected by horizontal bars. It is recommended to place large-scale marking plates on jacks.
Sufficient surface area for work. Conventional tables have dimensions: length 2000–3000 mm; width 4000–5000 mm; height 700–1000 mm. The surface area of the table should be suitable for the dimensions of the sheets, tapes, and strips of material.
Convenience. Tables are equipped with different devices:

weights for fixing sheets of light material;
prisms for installing pipes;
clamps for securing metal sheets;
rectangular and wedge-shaped gaskets for installing profiles and other parts.

The work site must be guaranteed with all the tools necessary for flat marking. The table provides a list of the necessary tools and certain tips for working with them.

Tool	Function	Design requirements	Tips for use
Scriber	drawing marked lines on workpieces	· thin steel rod; · one end is sharpened at 45 degrees, the other is bent into a ring; · the sharp end is hardened	· to obtain thin marks, the tip must be hard and sharp; · during operation, the scriber is deviated from the ruler in the direction of its movement; it should be regularly pressed against the ruler with its tip
Outline	drawing contours parallel to the edges of the sheet	· material: copper or steel; presence of a graphite pencil in the working part	Reismus	· checking the location of workpieces; · carrying out parallel risks	· stand with scriber fixed at the required height; · fixation height is measured with a square
Kerner	· construction of centers of circles or holes; · drawing holes on the marking lines	· material - hard steel; · dimensions: diameter 8-13 mm, length 90-150 mm; · the end is sharpened at 60 degrees; · there are manual and automatic (set marks of the same size)	The automatic center punch does not require a hammer to operate
Locksmith's hammer	percussion tool for punching	use hammers weighing 50 - 200 g	the work is performed with light movements conveyed by bending the hand “from the shoulder”
Squares	· construction and control of angles; restoration of perpendiculars	preferred material - metal	· it is advisable to have squares with angles of 30, 45, 60 degrees; · a square with a shelf is used to check the correct placement of parts on the plate
Protractor with protractor	marking corners and checking mark alignment	preferred material - metal	The position can be fixed with a hinge screw
Compass	· construction of circles, arcs; Transfer of dimensions from ruler to workpieces	It is recommended to harden the legs of the compass	the tip of the compass is installed strictly in the punched hole
Marking plate	Serves as a working surface; · used for equipment storage	· located horizontally; · must be clean and dry	placed on cabinets, stands with drawers, tables
Templates, stencils	simplification and acceleration of marking of similar parts	durable steel templates	ensure a tight fit of the template to the workpiece
Vise	tool for securing small parts	ensuring smooth tightening efforts	For fine work, a small step is recommended; for coarse clamping, a wide step is recommended.

Marking boards

Marking plates have a ribbed design, which gives them rigidity with a relatively low weight.

The working surfaces of marking plates must be precisely machined. To avoid deformation of the slabs during their operation, the castings are subjected to aging (exposure to air for a long time) between roughing and finishing processing.

On the upper surface of the marking plate (Fig. 1, a), in the absence of machine grooves, longitudinal and transverse grooves with a depth and width of 1-2 mm are cut so that the entire surface of the plate is divided into square sections.

What you need to know about the center punch

When choosing a core sample, you need to remember several important points about this type of instrument.

Firstly, it does not matter at all what cross-sectional shape the tool rod has.

It is much more important to pay attention to its other characteristics. Secondly, you should buy a device based on the diameter and type of drill with which it will be used

Secondly, you should buy a device based on the diameter and type of drill with which it will be used.

Thirdly, if you plan to use a center punch when working with soft metals, it is better to choose one with a smaller sharpening angle and vice versa.

Applying marks

The standard regulates the procedure for drawing marking lines:

horizontal;
vertical;
inclined;
curvilinear.

Applying curved elements after straight ones provides another opportunity to check their accuracy. The arcs must close the straight lines, the interface must be smooth.

Tools for marking

Direct marks are carried out with a well-sharpened scriber, without tearing off, in one step. At the same time, the scriber is tilted away from the ruler or square so as not to introduce distortions.

Parallel lines are drawn using a square and moving it along the reference ruler to the required distance.

If the workpiece already has holes, then a special tool, a center finder, is used to attach marking lines to them.

Center finder

In order to mark inclined lines, use a marking protractor with a hinged ruler fixed at its zero point.

Marking protractor

For particularly precise markings in plumbing, calipers are used. They allow you to measure distances and scratch marks with an accuracy of hundredths of a millimeter.

Marking of metal products and blanks: tools, methods, rules | Construction Bulletin

In the production of metal products, the source material - castings, sheet and profile products - does not correspond in size and shape to the designer's drawing. To cut off excess metal, drill, stamp, weld, or otherwise process a workpiece, key points of the drawing are applied to it. Applying to these points and lines, the processing is carried out.

Basic concept and types of markup

As a rule, unique parts and products produced in small and ultra-small series are marked. For large-scale and mass production, workpieces are not marked; instead, special equipment and control programs are used.

What is markup

The operation of applying the dimensions and shape of a product to workpieces is called marking. The purpose of the operation is to designate the places where the part should be processed and the boundaries of these actions: drilling points, bend lines, weld lines, markings, etc.

Marking is done with points, which are called cores, and lines, which are called risks.

Marks are scratched into the metal surface with a sharp tool or applied with a marker. Cores are filled with a special tool - a center punch.

According to the method of execution, there are such types of markup as:

Manual. It is made by mechanics.
Mechanized. Performed using mechanization and automation tools.

Based on the application surface, they are distinguished

Superficial. It is applied to the surface of the workpiece in one plane and is not associated with the lines and marking points applied to other planes.
Spatial. It is carried out in a unified three-dimensional coordinate system.

Notes on straightening and marking for thin sheet metal

The choice between surface and spatial markings is determined, first of all, by the complexity of the spatial configuration of the part.

Markup requirements

Plumbing markings must meet the following requirements:

accurately convey the key dimensions of the drawing;
be clearly visible;
not to be abraded or lubricated during mechanical and heat treatment operations;
do not degrade the appearance of the finished product.

Marking of parts must be carried out with high-quality inventory tools and devices that are subject to periodic verification.

Applying marks

The standard regulates the procedure for drawing marking lines:

horizontal;
vertical;
inclined;
curvilinear.

Applying curved elements after straight ones provides another opportunity to check their accuracy. The arcs must close the straight lines, the interface must be smooth.

Direct marks are carried out with a well-sharpened scriber, without tearing off, in one step. At the same time, the scriber is tilted away from the ruler or square so as not to introduce distortions.

Parallel lines are drawn using a square and moving it along the reference ruler to the required distance.

If the workpiece already has holes, then a special tool, a center finder, is used to attach marking lines to them.

In order to mark inclined lines, use a marking protractor with a hinged ruler fixed at its zero point.

For particularly precise markings in plumbing, calipers are used. They allow you to measure distances and scratch marks with an accuracy of hundredths of a millimeter.

Marking marking lines

In order to more accurately carry out the risk, cores are placed at its beginning and end. This allows you to visually control the position of the ruler while drawing.

On long-distance risks, auxiliary cores are also placed through

every 5-15 cm.

Circle lines are marked at four points - the ends of perpendicular diameters.

If already treated surfaces are marked, then punching is used only at the beginning and end of the marks.

After finishing, the marks are extended to the side surfaces and the cores are placed on them.

Marking techniques

The following techniques are used in plumbing:

According to the template. Used in case of small-scale production. The template is made from rolled metal, the entire batch is marked (or even processed) through once marked slots and holes in this sheet. For parts with complex shapes, several templates can be made for different planes.
Following the example. The dimensions are transferred from the part - the sample. It is used in the manufacture of a new part to replace a broken one.
Local. Used in the production of complex multi-component products and structures. Blanks are placed on a plane or in space in the order in which they enter the final product and are marked together.
Pencil (or marker). Used for workpieces made of aluminum alloys so that the scriber does not destroy the passivated protective layer.
Accurate. It is done using the same methods, but special precision measuring and marking tools are used.

The selection of techniques is carried out in accordance with design and technological instructions.

Marriage during marking

First of all, when marking, defects that were made at previous stages of production emerge. Products from procurement sites or workshops, as well as materials purchased from other enterprises, reveal:

violation of dimensions
shape distortion
warping.

Such castings or rentals are not subject to further marking operations, but are returned to the department or organization that caused the defect to correct it.

At the marking stage itself, defects can be caused by the following factors:

Inaccurate drawing. The mechanic, without hesitation, displays incorrect dimensions on the part, and during further processing, defective products come out.
Inaccuracy or malfunction of instruments. All marking tools are subject to mandatory periodic verification by the metrological service of the enterprise or an authorized metrological center.
Incorrect use of tools or marking accessories. There are known cases when instead of calibrated measuring pads, ordinary pads were used to set the level. In this case, erroneous application of angles and slopes is also possible.
Inaccurate placement of the workpiece on the marking table or plaza. They lead to distortions when setting aside dimensions, violation of parallelism and coaxiality.
Wrong choice of reference planes. It is also possible that some of the dimensions were applied from the base planes, and some from the rough surfaces of the workpiece.

Separately among the reasons for defects are the marker's errors. These include:

Incorrectly read drawing. It is possible to apply a radius instead of a diameter and vice versa, inaccurate application of the centers of holes relative to the center marks, etc. If any difficulties arise, the mechanic must seek clarification from the foreman or foreman.
Carelessness and inattention when punching and drawing lines.

The human factor, unfortunately, is the most common cause of marking defects.

Negligence can be committed by both the mechanic himself and his supervisors, who did not check the tool on time or issued inappropriate marking devices.

Typically, marking operations are entrusted to the most experienced and responsible workers, counting on the fact that they will not mechanically transfer dimensions from the drawing to the workpiece, but will treat the matter thoughtfully and promptly notice and eliminate the reasons for possible defects on their own or by contacting their managers.

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What is a marking operation?

It should be immediately clear that marking does not necessarily mean fixing the distance from one point to another when constructing a particular structure. As production and construction standards become more complex, the manufacturability of marking processes also increases. During this action, a foreman at a construction site or an operator on a production line can determine the parameters of the workpiece, the characteristics of its location relative to other objects, etc. A modern marking tool allows you to record indicators such as length, width, height and angle. Some models such as squares are also focused on initially determining how well an object, its parameters or location meet the requirements. As for the marking process, it mainly involves manual handling of measuring and marking devices. The user, in turn, is required to be attentive, accurate and thorough in removing and recording data.

Marking. Marking a workpiece or part

Marking is the operation of applying lines (so-called marking marks) to the workpiece being processed or the part being repaired, defining the contours of the part or the area to be processed.

Marking of parts is used mainly in small-scale production of parts and when carrying out metalwork repair work.

To carry out various marking work, a mechanic must have special measuring and marking tools (rulers, thickness gauges, scribers, punches, etc.).

To install, align and secure the marked parts, use a set of special devices (linings, prisms, squares, etc.).

Marking is done on marking plates, on which all fixtures and tools are placed.

Marking boards

Marking plates have a ribbed design, which gives them rigidity with a relatively low weight.

Large marking plates are installed on special stands (pedestals) with drawers for storing tools. Small marking plates are placed on wooden stands and installed directly on workbenches.

The height from the floor to the working surface of a marking slab of small or medium sizes is 800–900 mm, and of large slabs – 700 mm.

The marking plate must have free space to walk around and to be able to work from either side.

Checking the flatness of the marking plates is carried out using an accurate ruler and feeler gauge. To do this, the ruler is placed with its working surface on the working surface of the marking plate. The gaps between these surfaces are controlled with a feeler gauge. The thickness of the probe, which passes into the gap between the ruler and the marking plate, should not exceed 0.03–0.05 mm.

The correctness of the working surfaces of scraped marking plates (Fig. 1, b), intended for precise marking and verification work, is checked for paint using a straight edge. The number of spots in a 25x25 mm square must be at least 12.

Rice. 1. Marking boards

Equipment

In order to install the part on the working plane of the marking plate, support pads, prisms, jacks, special devices, cubes and squares are used, which have precisely machined prismatic and vertical surfaces perpendicular to the surface of the plate. Shims are also used to protect the working surface of the marking plate from damage by the untreated (black) surfaces of the parts being marked.

Flat (Fig. 2, a) and prismatic (Fig. 3) pads are placed directly on the working surface of the marking plate.

Rice. 2. Pads for installing the part on the marking plate

Rice. 3. Prism (a) and square (b) for installing parts

Parts that have a flat base, a flat end, or three supports spaced at a maximum distance along the dimensions of the part must be installed for marking on three pads selected in height.

If it is necessary to orient the part in a horizontal plane, then select pads or a set of pads for the supports, in which the part will take a horizontal position. In this case, it is also convenient to use height-adjustable pads. In Fig.

2, b shows an adjustable lining, which is adjusted in height by rotating screw 1, which moves wedge 2 along wedge 3. On the side surface of the lower wedge there is a scale that allows you to more accurately set the height of the lining.

Cylindrical parts are placed on prismatic supports with triangular cutouts (Fig. 3, a). A set of auxiliary tools usually contains several of these pads with the same cutouts.

For ease of marking, the part can be fixed to a square (Fig. 3, b) installed on the marking plate. The shelves of the square have through holes through which the part can be attached to the square.

THEORETICAL INFORMATION

METAL MARKING

Textbook Plumbing B.S. Pokrovsky, V.A. Horse pp. 51- 67

Purpose and types of markings

Metal marking is the operation of applying lines (scores) to the workpiece, which, according to the drawing, determine the contours of the part and the places to be processed.

Marking lines can be contour, control or auxiliary.

Contour marks determine the contour of the future part and show the boundaries of processing.

Control marks are carried out parallel to the contour lines “into the body” of the part. They serve to check the correct processing.

Auxiliary marks mark axes of symmetry, centers of radii of curvatures, etc.

Marking of workpieces creates conditions for removing metal allowance from workpieces to specified boundaries, obtaining a part of a certain shape, required dimensions and for maximum savings in materials.

Marking is divided into linear (one-dimensional), planar (two-dimensional) and spatial or volumetric (three-dimensional).

Linear marking is used when cutting shaped steel, preparing blanks for products made of wire, rod, strip steel, etc., that is, when the boundaries, for example, of cutting or bending, are indicated by only one dimension - length.

Planar marking is the application of various lines to the surfaces of flat workpieces on sheet and strip metal, as well as on the surfaces of cast and forged parts.

Planar marking is usually used when processing parts made of sheet metal. Planar marking also includes the marking of individual planes of parts of complex shapes, if the relative position of the marked planes is not taken into account.

When marking in space, marking lines are applied in several planes or on several surfaces.

Spatial marking is the most complex of all types of marking. Its peculiarity lies in the fact that not only individual surfaces of the workpiece are marked, located in different planes and at different angles to each other, but also the location of these surfaces is mutually linked to each other.

Various marking methods are used: according to a drawing, template, sample and in place. The choice of marking method is determined by the shape of the workpiece, the required accuracy and the number of products. When marking a part is repeated multiple times, a template is used. When using CNC machines, there is no need for marking.

When marking according to a drawing, axial lines are first drawn, then horizontal and vertical lines, and lastly, inclined lines, circles and arcs. After this, the contours of the part are marked.

In addition to the considered markings according to the drawing, markings according to the template are used.

The template is used when making parts or checking them after processing. Marking according to a template is carried out when producing large batches of identical parts. It is advisable because it allows you to avoid repeating labor-intensive and time-consuming markings according to the drawing if you do it once when making the template. All subsequent operations of marking blanks consist of copying the outlines of the template. In addition, templates can be used to control the part after processing the workpiece.

Templates are made from sheet material 1.5-3 mm thick.

Marking in place is carried out in cases where the parts are mating, and one of them is connected to the other in a certain position. In this case, one of the parts acts as a template.

The process of transferring the contour of a part, its bend lines, cutouts and other markings from the template to the metal is called basting.

Depending on the shape of the blanks and parts to be marked, marking can be planar and spatial (volumetric).

When marking spatially, it is very important to correctly maintain the relative position of the planes on which the marking is carried out.

When marking, allowances for subsequent processing and assembly are taken into account. If the parts are connected with an overlap, then the dimensions of the parts must be increased by the amount of this overlap. The allowance for processing edges after cutting them with scissors is 2 - 3 mm, and for gas cutting - 4 mm. Cylindrical and conical parts are marked taking into account the thickness of the metal. The marking should ensure cutting of metal with the least waste.

The accuracy of marking significantly affects the quality of processing. The degree of marking accuracy ranges from 0.25 – 0.5 mm.

Errors made during marking lead to defects.

Technical requirements

The technical requirements of marking include, first of all, the quality of its execution, on which the accuracy of the manufacture of parts largely depends.

The marking must meet the following basic requirements:

1) exactly correspond to the dimensions indicated in the drawing;

2) marking lines (marks) must be clearly visible and not erased during processing of the part;

3) do not spoil the appearance and quality of the part, i.e. the depth of the marks and core recesses must meet the technical requirements for the part.