engineer drawing

Everything you need to know about engineering drawing

Everything you need to know about engineering drawing

The engineering drawing in our life plays a big role. In ancient times, there were numerous drawings and hieroglyphs on stones, in caves and rocks, on various objects and weapons. To create a drawing that accurately and effectively depicts the shape and size of an item to manufacture.

The engineering drawings Products include all industrial products, and the methods of drawing them, that is, drawing methods, include mechanical drawing , civil engineering drawings , architectural drawings , electrical drawings, chemical drawings, and clothing drawings due to their particular characteristics.

For some time now, the manufacture of any model begins with the execution of its sketch, which allows you to determine not only the shape and size of all parts of the object, but also get a visual idea of ​​it. The first techniques from the technique of displaying objects were created over many centuries. They were performed in a way that was scientifically substantiated only at the end of the 18th century by the founder of descriptive geometry, the scientist G. Monge.

What is engineering drawing?

CNC manufacturing parts

An engineering drawing is an international idea for the transfer of graphic information and a means of expressing the intentions of a designer, and the main production document, according to which assemblies, mechanisms, devices and their basic components are made.

The engineering drawing basics image of the body consists of two or more interconnected images, made according to the rules of rectangular projection, in compliance with the rules and conventions set forth in the standards technically “savvy” performer.

The engineering drawing is the indispensable element for any type of project, construction, mechanical, fashion, goldsmith, industrial design (the design), etc. Unlike other forms of graphic representation, in addition to showing us an image of the object, the engineering drawing provides an exact description of the shape, size and type of material of which the object is made.

It is a form of communication through images between those who elaborate the project and those who have to concretely carry it out (between the architect and the craftsman, between the stylist and the tailor, between a designer and a manufacturer, etc.), so it must be as clear, legible and easily understandable as possible even by a non-specialized person, but who may be interested in the object described. 

Engineering drawing is performed with ruler and square, with drafting machines, but more often with computers equipped with cutting program dedicated to design.

To be called “technical” a drawing, to whatever sector it belongs, must have four characteristics:

  1. Be reproduced on an adequate scale;
  2. Be performed in orthogonal projection;
  3. To be carried out using conventional and parallel lines;
  4. Be completed with quotas (“measures”).

The engineering drawing is a graphic representation of geometric elements present in space. The rules underlying all technical representations are dictated by descriptive geometry, according to which a spatial meaning is associated with every single sign.

Engineering Drawing Basics

The engineering drawings that come out of a technical office must contain all the information necessary for the manufacture of the piece or assembly represented.

When it is necessary to design a mechanism or when, once the machining of its various and often numerous parts has been completed, it is necessary to assemble the mechanism itself, use is made of the overall drawings.

These represent the whole, using the number of isometric view, together, when necessary, with one or more sections.

The task of providing all the elements mentioned is carried out by the third angle projection drawings. These give all the views and sections necessary for the complete identification of their exact shape and size, therefore accompanied by the general right dimensions and tolerances, the machining marks of the various parts of each piece, the indications of the materials, including any inclined surface treatments or finishes to which the materials must be subjected.

The engineering drawing can be two-dimensional (2D) and three-dimensional prints (3D).

The two-dimensional prints representation methods represent an object in its different views (top, side, front), also called orthogonal projections.

The purpose of the Engineering drawing?

Engineering drawing also provides a theoretical basis for studying other general engineering disciplines: strength of materials, the theory of mechanisms and cnc machines and machine parts, to draw up design work in accordance with current state standards, specifications and other regulatory documents.

1. Process Manufacturing

When we make a workpiece, it makes sense to make a drawing beforehand. Because before we build something, we have to plan the construction using drawings. This enables us to identify and eliminate possible errors as early as the planning stage. In addition, we do not waste expensive material during production.

In a society based on the division of labour, design and production are separate. The engineering drawing board serves as a means of communication between planning and production. The manufacturing engineer must be able to bring ideas into the form of an engineering drawing. 

The worker in production, on the other hand, must be able to read the engineering drawing number correctly and work exactly according to the specifications.

2. Standardization

The engineering drawings must be clear and understood by everyone involved in the production process. That is why there are binding rules, the norms. An engineering drawing consists of parallel lines, numbers, auxiliary lines and symbols. Shapes and dimensions of objects are thus represented uniformly. Terms have a common meaning.

Engineering drawing and thus CAD/CAAD is mainly used in various areas of engineering, especially in construction, since it is precisely these professional areas that have to create the basis for the manufacture of a product.

Otherwise, engineering drawing is also used by architects, draftsmen and technical draftsmen in the form of CAAD. The two latter professions, architectural draftsman and technical draftsman, require training.

Both courses last three years and do not usually require a high school diploma while architecture and all engineering professions are still majors.

Engineering drawing is therefore primarily part of the areas:

  • Mechanical and plant engineering
  • Electrical engineering, drive technology, etc.
  • Architecture and construction

How to make engineering drawing?

When engineering drawing a detail, the following sequence is recommended:

  1. Select the main image.

  2. Set the number of images – views, sections, sections, remote elements, which unambiguously give an idea of ​​the shape and dimensions of the part, and supplementing the main image with any information, remembering that the number of images in the drawing should be minimal and sufficient.

  3. Select the image scale according. For images on working drawings, a scale of 1:1 is preferred. The scale on the detail drawing does not always have to match the scale of the assembly drawing. Large and not complex details can be drawn on a reduction scale (1:2; 1:2.5; 1:4; 1:5, etc.), small elements are better depicted on an enlargement scale (2:1; 2.5 :1; 4:1; 5:1; 10:1; etc.).

  4. Select a mechanical drawing format. The format is selected depending on the size of the part, the number and scale of images. Images and inscriptions should occupy approximately 2/3 of the working area of ​​the format. The working field of the format is limited by a frame for the design of drawings. The main inscription is located in the lower right corner (on A4 format, the main inscription is located only along the short side of the sheet);

Execute the layout of the drawing

  1. For rational filling of the format field, it is recommended to outline the overall rectangles of the selected images with thin break lines, then draw the axes of symmetry. The distance between the images and the format frame should be approximately the same. It is selected taking into account the subsequent drawing of extension, dimension lines and corresponding inscriptions.

  2. Draw detail. Apply extension and dimension lines. After completing the drawing of the part with thin lines, remove the extra centre lines. Having chosen the thickness of the main line, circle the images, observing the ratio of vertical lines. The outline must be clear. After the stroke, make the necessary inscriptions and put down the numerical values ​​​​of the dimensions above the dimension centre lines.

  3. Fill in the title block. At the same time, indicate: the name of the part (assembly measurement units), the material of the part, its code and number, by whom and when the drawing was made, etc.

Stiffeners, spokes in longitudinal sections are shown not shaded.

In the technical drawing In the jargon of the technical drawing, the title block is a box in the sheet (usually placed in a corner, generally in the lower right corner) in which all the information necessary to better understand the overall depicted is contained.

Where should the title block be placed in a technical

Inscription box (title block) The sheet must contain both the drawing and the inscription box (title block), whose location for formats A0 to A3 is in the lower right corner of the drawing area , these formats must be positioned horizontally.

How to make the title blocks on a sheet?

  1. Start new blank technical drawings.
  2. Draw theborder of the drawing using standard AutoCAD objects and commands.
  3. Enter ATTDEF at the command line to insert attribute definition objects. …
  4. Enter thetag name, for example DESC1, DESC2, SHEET, SHEET_TOTAL.

Dimensioning is the most critical part of the work on the drawing, as incorrectly affixed and extra dimensions lead to marriage, and lack of dimensions causes production delays. The following are some guidelines for dimensioning when making part drawings.

The dimensions of the part are measured using a gauge in the general view drawing of the assembly unit, taking into account the scale of the drawing (with an accuracy of 0.5 mm). When measuring the largest thread diameter, it is necessary to round it up to the nearest standard, taken from the reference book.

Size classification

All sizes are divided into two groups: basic (conjugated) and free.
The main dimensions are included in the dimensional chains and determine the relative position of the part in the assembly, they must provide:

  • the location of the part in the node;
  • the accuracy of the interaction of the assembled parts;
  • assembly and disassembly of the product;
  • Interchangeability of parts.

Making an engineering drawing of a part made from a sheet

This type of parts includes gaskets, covers, strips, wedges, plates, etc. Details of this shape are processed in various ways (stamping, milling, planning, and cutting plane lines with scissors). Flat parts made of sheet material are depicted, as a rule, in one projection that defines the contour of the part.

 The thickness of the material is indicated in the main inscription, but it is recommended to indicate it again on the image of the part, on the mechanical drawingIf the part is bent, then often a scan is shown in the drawing.

Execution of a drawing of a part made by casting, followed by machining

Forming by casting makes it possible to obtain a rather complex shape of a part, with virtually no loss of material. But after casting, the surface is quite rough, therefore, the working surfaces require additional machining.
Thus, we obtain two groups of surfaces – foundry (black) and processed after casting (clean).
Casting process: molten material is poured into the mold, after cooling, the workpiece is removed from the mold, for which most of the surfaces of the workpiece have casting slopes, and the mating surfaces have casting radii of fillets.

Casting slopes cannot be depicted, and casting radii must be depicted without fail. The dimensions of the casting radii of roundings are indicated in the technical requirements of the drawing by writing, for example: Unspecified casting radii 1.5 mm.

The main feature of applying dimensions: since there are two groups of surfaces, that is, two groups of sizes, one connects all black surfaces, the other – all clean ones, and for each coordinate direction it is allowed to put down only one dimension connecting these two groups of sizes.

Factors that must be indicated in engineering drawings

The specification for training assembly drawings, as a rule, includes the following sections:

  1. Documentation;
  2. Complexes;
  3. Assembly units;
  4. Details;
  5. Standard products;
  6. Other products;
  7. materials;

The name of each section is indicated in the column “Name”, underlined with a thin drawing line and highlighted with empty hidden lines.

  1. In the “Documentation” section, design documents for the assembly unit are entered. In this section in the training drawings enter the “Assembly drawing board”.
  2. The sections “Assembly units” and “Details” include those basic components of the assembly unit that are directly included in it. In each of these sections, the constituent parts are recorded by their name.
  3. In the section “Standard products” write down products used according to state, industry or republican standards. Within each category of standards, the record is made in homogeneous groups, within each group – in alphabetical order of product names, within each name – in ascending order of standard designations, and within each standard designation – in ascending order of the main parameters or dimensions of the product.
  4. In the “Materials” section, all materials that are directly included in the assembly unit are entered. Materials are recorded by type and in the sequence. Within each type, materials are recorded in alphabetical order of the names of materials, and within each name – in ascending size and other parameters.

Contents of the engineering drawing of the part

A working drawing of a part is a design document containing an image of the part and other data necessary for its manufacture and control.

The working drawing must contain:

a minimum but sufficient number of images (isometric view, sections, sections, detail elements) that fully reveal the shape of the part required dimensions with their limit deviations surface roughness information about material, heat treatment, coating, finishing technical requirements

Basic requirements for the execution of drawings of parts
  1. Each detail technical drawing is performed on a separate format
  2. The technical drawing must contain the main inscription, which is located in the lower right corner of each format. For all formats with the exception of the A4 format, the main inscription can be located both along the long and along the short side.

 On the A4 format, the main inscription should be placed only along the short side. The designation of the drawing is applied in font No. 10. The name of the part and its material is written in the nominative singular, starting with a noun

Engineering graphics - execution of drawings

We offer the execution of assembly drawings on the subject of engineering graphics. The drawings are made in the Compass and AutoCAD programs. Engineering Drawings can also be made by hand, on paper drawing or graph paper, depending on the requirements for the drawings. Isometric Drawings made on paper are sent by mail. Delivery times vary.

The terms for the production of engineering drawings according to engineering graphics depend on the method of execution (by hand or in electronic form), as well as the amount of work. The deadlines for completing such drawings in Compass and Auto CAD software are naturally less than drawings by hand. 

Therefore, if possible, order engineering drawings in electronic form. It takes less time to complete them, and therefore, the price will be lower than for freehand drawings. Now, more and more often, universities allow the execution of drawings on the subject of engineering graphics and in electronic form. 

But not everywhere and not always, therefore, before placing an order for work, be sure to check with the teacher in what form the completed task can be provided.


Q: How do to find a professional engineer by google?

A: To find the professional engineer on Google you can visit several platforms of freelancing websites including fiverr. Although there is multiple companies which offer seasoned services online but their services are quite expensive. In addition LinkedIn is also a good platform to find expert engineers online.

Q: What is the cost of engineering drawing on fiverr?

The cost of engineering drawing on fiverr varies according to the manufacturing engineer seller level. If the seller level is higher, he will charge more money as compared to a new seller who is struggling to set his portfolio. The average price of engineering drawing on fiverr is $60.

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