How to Draw Plan View Flag Symbol

Type of technical drawing used to ascertain requirements for engineered items

An engineering cartoon is a type of technical cartoon that is used to convey information most an object. A common use is to specify the geometry necessary for the construction of a component and is called a detail cartoon. Unremarkably, a number of drawings are necessary to completely specify fifty-fifty a simple component. The drawings are linked together by a master drawing or assembly drawing which gives the drawing numbers of the subsequent detailed components, quantities required, construction materials and possibly 3D images that can be used to locate individual items. Although mostly consisting of pictographic representations, abbreviations and symbols are used for brevity and additional textual explanations may also exist provided to convey the necessary information.

The process of producing engineering drawings is oft referred to as technical drawing or drafting (draughting).^[1] Drawings typically contain multiple views of a component, although additional scratch views may be added of details for further explanation. Only the information that is a requirement is typically specified. Central data such every bit dimensions is commonly only specified in one place on a cartoon, avoiding redundancy and the possibility of inconsistency. Suitable tolerances are given for critical dimensions to permit the component to be manufactured and office. More than detailed production drawings may be produced based on the information given in an technology drawing. Drawings take an data box or championship block containing who drew the drawing, who approved information technology, units of dimensions, meaning of views, the title of the drawing and the drawing number.

History [edit]

Technical drawing has existed since ancient times. Complex technical drawings were made in renaissance times, such equally the drawings of Leonardo da Vinci. Modernistic engineering science drawing, with its precise conventions of orthographic project and scale, arose in France at a time when the Industrial Revolution was in its infancy. L. T. C. Rolt'due south biography of Isambard Kingdom Brunel^[2] says of his father, Marc Isambard Brunel, that "It seems fairly certain that Marc'due south drawings of his cake-making mechanism (in 1799) made a contribution to British engineering technique much greater than the machines they represented. For it is safe to assume that he had mastered the art of presenting three-dimensional objects in a ii-dimensional plane which nosotros at present call mechanical drawing. Information technology had been evolved by Gaspard Monge of Mezieres in 1765 but had remained a military underground until 1794 and was therefore unknown in England."^[2]

Standardization and disambiguation [edit]

Engineering drawings specify requirements of a component or assembly which can exist complicated. Standards provide rules for their specification and interpretation. Standardization also aids internationalization, because people from different countries who speak unlike languages can read the same engineering drawing, and translate information technology the same way.

One major set of technology drawing standards is ASME Y14.5 and Y14.5M (most recently revised in 2009). These utilise widely in the United States, although ISO 8015 (Geometrical production specifications (GPS) — Fundamentals — Concepts, principles and rules) is now also important.

In 2011, a new revision of ISO 8015 (Geometrical product specifications (GPS) — Fundamentals — Concepts, principles and rules) was published containing the Invocation Principle. This states that, "In one case a portion of the ISO geometric product specification (GPS) system is invoked in a mechanical engineering production documentation, the entire ISO GPS system is invoked." It besides goes on to state that marker a drawing "Tolerancing ISO 8015" is optional. The implication of this is that any drawing using ISO symbols can only be interpreted to ISO GPS rules. The simply style not to invoke the ISO GPS system is to invoke a national or other standard. Britain, BS 8888 (Technical Production Specification) has undergone important updates in the 2010s.

Media [edit]

For centuries, until the 1970s, all engineering drawing was done manually by using pencil and pen on paper or other substrate (e.g., vellum, mylar). Since the advent of computer-aided design (CAD), engineering drawing has been done more and more in the electronic medium with each passing decade. Today most engineering drawing is done with CAD, just pencil and paper have not entirely disappeared.

Some of the tools of manual drafting include pencils, pens and their ink, straightedges, T-squares, French curves, triangles, rulers, protractors, dividers, compasses, scales, erasers, and tacks or push pins. (Slide rules used to number amid the supplies, too, but present fifty-fifty manual drafting, when it occurs, benefits from a pocket calculator or its onscreen equivalent.) And of grade the tools also include drawing boards (drafting boards) or tables. The English idiom "to go back to the cartoon board", which is a figurative phrase meaning to rethink something altogether, was inspired by the literal deed of discovering pattern errors during production and returning to a drawing lath to revise the engineering drawing. Drafting machines are devices that aid transmission drafting by combining drawing boards, straightedges, pantographs, and other tools into one integrated drawing environment. CAD provides their virtual equivalents.

Producing drawings usually involves creating an original that is then reproduced, generating multiple copies to be distributed to the shop floor, vendors, company archives, and and then on. The classic reproduction methods involved blue and white appearances (whether white-on-blueish or blue-on-white), which is why engineering drawings were long chosen, and even today are still oft chosen, "blueprints" or "bluelines", even though those terms are anachronistic from a literal perspective, since most copies of engineering drawings today are made past more modernistic methods (often inkjet or light amplification by stimulated emission of radiation press) that yield blackness or multicolour lines on white paper. The more generic term "print" is now in common usage in the U.S. to mean whatsoever paper copy of an engineering drawing. In the case of CAD drawings, the original is the CAD file, and the printouts of that file are the "prints".

Systems of dimensioning and tolerancing [edit]

Almost all engineering drawings (except perhaps reference-only views or initial sketches) communicate not simply geometry (shape and location) but as well dimensions and tolerances^[one] for those characteristics. Several systems of dimensioning and tolerancing have evolved. The simplest dimensioning organization just specifies distances between points (such equally an object's length or width, or hole centre locations). Since the appearance of well-adult interchangeable industry, these distances have been accompanied past tolerances of the plus-or-minus or min-and-max-limit types. Coordinate dimensioning involves defining all points, lines, planes, and profiles in terms of Cartesian coordinates, with a common origin. Coordinate dimensioning was the sole all-time pick until the postal service-Globe War II era saw the development of geometric dimensioning and tolerancing (GD&T), which departs from the limitations of coordinate dimensioning (e.m., rectangular-only tolerance zones, tolerance stacking) to allow the nigh logical tolerancing of both geometry and dimensions (that is, both course [shapes/locations] and sizes).

Common features [edit]

Drawings convey the following critical information:

Geometry – the shape of the object; represented equally views; how the object will look when it is viewed from diverse angles, such as forepart, top, side, etc.
Dimensions – the size of the object is captured in accepted units.
Tolerances – the allowable variations for each dimension.
Textile – represents what the item is made of.
End – specifies the surface quality of the item, functional or cosmetic. For example, a mass-marketed product usually requires a much higher surface quality than, say, a component that goes inside industrial machinery.

Line styles and types [edit]

Standard engineering science cartoon line types

A multifariousness of line styles graphically represent physical objects. Types of lines include the following:

visible – are continuous lines used to draw edges straight visible from a particular angle.
hidden – are brusk-dashed lines that may exist used to stand for edges that are not directly visible.
center – are alternately long- and short-dashed lines that may be used to represent the axes of circular features.
cutting plane – are thin, medium-dashed lines, or thick alternately long- and double short-dashed that may be used to define sections for department views.
section – are thin lines in a pattern (pattern determined past the material existence "cutting" or "sectioned") used to indicate surfaces in section views resulting from "cut". Section lines are commonly referred to equally "cross-hatching".
phantom – (not shown) are alternately long- and double short-dashed thin lines used to represent a feature or component that is not part of the specified function or associates. East.k. billet ends that may be used for testing, or the machined product that is the focus of a tooling drawing.

Lines can also be classified by a letter classification in which each line is given a letter.

Blazon A lines show the outline of the feature of an object. They are the thickest lines on a drawing and done with a pencil softer than HB.
Type B lines are dimension lines and are used for dimensioning, projecting, extending, or leaders. A harder pencil should exist used, such equally a 2H pencil.
Type C lines are used for breaks when the whole object is not shown. These are freehand drawn and only for brusque breaks. 2H pencil
Type D lines are similar to Type C, except these are zigzagged and only for longer breaks. 2H pencil
Type E lines betoken hidden outlines of internal features of an object. These are dotted lines. 2H pencil
Type F lines are Blazon East lines, except these are used for drawings in electrotechnology. 2H pencil
Type Grand lines are used for eye lines. These are dotted lines, only a long line of 10–20 mm, then a 1 mm gap, and so a pocket-sized line of 2 mm. 2H pencil
Blazon H lines are the same every bit blazon G, except that every 2d long line is thicker. These indicate the cutting aeroplane of an object. 2H pencil
Type Grand lines indicate the alternate positions of an object and the line taken by that object. These are drawn with a long line of 10–xx mm, so a small-scale gap, then a small-scale line of ii mm, then a gap, then another minor line. 2H pencil.

Multiple views and projections [edit]

Image of a part represented in first-angle projection

Symbols used to define whether a projection is either first-bending (left) or third-angle (right).

Several types of graphical projection compared

Various projections and how they are produced

Isometric view of the object shown in the engineering drawing below.

In most cases, a single view is not sufficient to show all necessary features, and several views are used. Types of views include the following:

Multiview projection [edit]

A multiview project is a type of orthographic projection that shows the object as it looks from the front, right, left, top, bottom, or dorsum (east.g. the primary views), and is typically positioned relative to each other according to the rules of either first-bending or tertiary-bending projection. The origin and vector management of the projectors (also chosen projection lines) differs, as explained below.

In offset-angle project, the parallel projectors originate as if radiated from behind the viewer and pass through the 3D object to project a 2nd image onto the orthogonal plane behind information technology. The 3D object is projected into second "paper" infinite every bit if you were looking at a radiograph of the object: the top view is under the forepart view, the correct view is at the left of the front view. First-bending projection is the ISO standard and is primarily used in Europe.
In third-angle projection, the parallel projectors originate as if radiated from the far side of the object and laissez passer through the 3D object to project a second image onto the orthogonal plane in front of it. The views of the 3D object are like the panels of a box that envelopes the object, and the panels pivot as they open up flat into the plane of the drawing.^[3] Thus the left view is placed on the left and the pinnacle view on the top; and the features closest to the front end of the 3D object will appear closest to the forepart view in the drawing. Tertiary-angle projection is primarily used in the U.s. and Canada, where it is the default projection organization according to ASME standard ASME Y14.3M.

Until the late 19th century, start-bending projection was the norm in Northward America besides equally Europe;^[4] ^[5] but circa the 1890s, third-angle projection spread throughout the Northward American engineering and manufacturing communities to the point of becoming a widely followed convention,^[iv] ^[5] and it was an ASA standard by the 1950s.^[5] Circa World War I, British exercise was frequently mixing the utilize of both projection methods.^[4]

As shown in a higher place, the conclusion of what surface constitutes the front, back, top, and lesser varies depending on the projection method used.

Not all views are necessarily used.^[6] Generally but as many views are used equally are necessary to convey all needed information conspicuously and economically.^[7] The front, top, and right-side views are commonly considered the core grouping of views included by default,^[eight] but whatever combination of views may exist used depending on the needs of the particular design. In add-on to the 6 primary views (front, back, top, bottom, correct side, left side), whatever auxiliary views or sections may be included as serve the purposes of office definition and its communication. View lines or section lines (lines with arrows marked "A-A", "B-B", etc.) ascertain the direction and location of viewing or sectioning. Sometimes a note tells the reader in which zone(s) of the drawing to find the view or department.

Auxiliary views [edit]

An auxiliary view is an orthographic view that is projected into any aeroplane other than one of the 6 main views.^[9] These views are typically used when an object contains some sort of inclined aeroplane. Using the auxiliary view allows for that inclined airplane (and any other significant features) to be projected in their true size and shape. The true size and shape of whatever feature in an technology drawing tin simply exist known when the Line of Sight (LOS) is perpendicular to the plane beingness referenced. Information technology is shown like a three-dimensional object. Auxiliary views tend to make utilise of axonometric projection. When existing all by themselves, auxiliary views are sometimes known as pictorials.

Isometric projection [edit]

An isometric project shows the object from angles in which the scales along each centrality of the object are equal. Isometric project corresponds to rotation of the object by ± 45° nigh the vertical axis, followed past rotation of approximately ± 35.264° [= arcsin(tan(30°))] about the horizontal axis starting from an orthographic project view. "Isometric" comes from the Greek for "aforementioned measure". One of the things that makes isometric drawings so attractive is the ease with which 60° angles can be constructed with only a compass and straightedge.

Isometric project is a type of axonometric projection. The other two types of axonometric projection are:

Dimetric projection
Trimetric projection

Oblique projection [edit]

An oblique projection is a simple type of graphical projection used for producing pictorial, 2-dimensional images of three-dimensional objects:

it projects an image by intersecting parallel rays (projectors)
from the three-dimensional source object with the cartoon surface (project plan).

In both oblique projection and orthographic projection, parallel lines of the source object produce parallel lines in the projected prototype.

Perspective projection [edit]

Perspective is an guess representation on a flat surface, of an image as it is perceived by the eye. The two about characteristic features of perspective are that objects are drawn:

Smaller as their distance from the observer increases
Foreshortened: the size of an object's dimensions forth the line of sight are relatively shorter than dimensions across the line of sight.

Section Views [edit]

Projected views (either Auxiliary or Multiview) which show a cross section of the source object along the specified cut plane. These views are usually used to show internal features with more clarity than may exist available using regular projections or hidden lines. In assembly drawings, hardware components (e.g. nuts, screws, washers) are typically not sectioned. Section view is a half side view of object.

Scale [edit]

Plans are normally "scale drawings", meaning that the plans are drawn at specific ratio relative to the actual size of the identify or object. Various scales may be used for different drawings in a set. For example, a floor programme may be drawn at 1:50 (1:48 or one⁄4 ″ = ane′ 0″) whereas a detailed view may exist drawn at 1:25 (1:24 or i⁄2 ″ = 1′ 0″). Site plans are ofttimes drawn at i:200 or ane:100.

Scale is a nuanced subject in the utilise of engineering drawings. On one hand, it is a full general principle of engineering drawings that they are projected using standardized, mathematically sure project methods and rules. Thus, slap-up effort is put into having an technology drawing accurately depict size, shape, form, aspect ratios between features, and so on. And yet, on the other mitt, at that place is another general principle of engineering drawing that nearly diametrically opposes all this endeavour and intent—that is, the principle that users are non to scale the drawing to infer a dimension not labeled. This stern admonition is often repeated on drawings, via a average note in the title block telling the user, "Do Non SCALE Cartoon."

The caption for why these two nigh opposite principles can coexist is as follows. The outset principle—that drawings volition exist made and then advisedly and accurately—serves the prime goal of why technology cartoon fifty-fifty exists, which is successfully communicating function definition and acceptance criteria—including "what the part should look similar if you lot've made information technology correctly." The service of this goal is what creates a drawing that 1 even could scale and get an accurate dimension thereby. And thus the dandy temptation to do so, when a dimension is wanted but was not labeled. The 2d principle—that even though scaling the cartoon volition usually piece of work, one should notwithstanding never do it—serves several goals, such as enforcing total clarity regarding who has authority to discern blueprint intent, and preventing erroneous scaling of a drawing that was never drawn to calibration to brainstorm with (which is typically labeled "cartoon not to scale" or "calibration: NTS"). When a user is forbidden from scaling the drawing, s/he must turn instead to the engineer (for the answers that the scaling would seek), and s/he will never erroneously scale something that is inherently unable to be accurately scaled.

Only in some means, the appearance of the CAD and MBD era challenges these assumptions that were formed many decades ago. When role definition is defined mathematically via a solid model, the assertion that one cannot interrogate the model—the direct analog of "scaling the drawing"—becomes ridiculous; considering when part definition is defined this way, it is not possible for a drawing or model to exist "non to scale". A 2d pencil cartoon can be inaccurately foreshortened and skewed (and thus not to scale), yet still be a completely valid part definition every bit long every bit the labeled dimensions are the only dimensions used, and no scaling of the drawing by the user occurs. This is because what the drawing and labels convey is in reality a symbol of what is wanted, rather than a true replica of it. (For instance, a sketch of a hole that is clearly not round all the same accurately defines the part as having a truthful round hole, as long as the characterization says "10mm DIA", because the "DIA" implicitly but objectively tells the user that the skewed drawn circle is a symbol representing a perfect circumvolve.) Merely if a mathematical model—essentially, a vector graphic—is declared to be the official definition of the function, then any corporeality of "scaling the cartoon" tin can make sense; in that location may nevertheless be an error in the model, in the sense that what was intended is not depicted (modeled); but there tin can be no error of the "not to calibration" type—considering the mathematical vectors and curves are replicas, not symbols, of the part features.

Even in dealing with second drawings, the manufacturing world has changed since the days when people paid attention to the calibration ratio claimed on the impress, or counted on its accuracy. In the by, prints were plotted on a plotter to verbal scale ratios, and the user could know that a line on the drawing 15mm long corresponded to a 30mm part dimension because the drawing said "1:2" in the "scale" box of the title block. Today, in the era of ubiquitous desktop printing, where original drawings or scaled prints are often scanned on a scanner and saved every bit a PDF file, which is then printed at any percent magnification that the user deems handy (such as "fit to paper size"), users have pretty much given up caring what scale ratio is claimed in the "scale" box of the title cake. Which, under the dominion of "exercise not scale cartoon", never really did that much for them anyway.

Showing dimensions [edit]

Sizes of drawings [edit]

Sizes of drawings typically comply with either of two different standards, ISO (Earth Standard) or ANSI/ASME Y14.1 (American).

The metric drawing sizes stand for to international paper sizes. These developed further refinements in the second half of the twentieth century, when photocopying became cheap. Engineering drawings could be readily doubled (or halved) in size and put on the side by side larger (or, respectively, smaller) size of paper with no waste of space. And the metric technical pens were chosen in sizes and so that one could add together detail or drafting changes with a pen width changing by approximately a cistron of the square root of two. A total fix of pens would have the following neb sizes: 0.13, 0.18, 0.25, 0.35, 0.5, 0.vii, i.0, 1.5, and 2.0 mm. However, the International Organisation for Standardization (ISO) called for four pen widths and set a colour code for each: 0.25 (white), 0.35 (yellow), 0.v (brownish), 0.7 (blue); these nibs produced lines that related to various text grapheme heights and the ISO newspaper sizes.

All ISO paper sizes have the same attribute ratio, ane to the square root of 2, significant that a document designed for whatever given size can be enlarged or reduced to any other size and will fit perfectly. Given this ease of changing sizes, it is of class common to re-create or print a given document on different sizes of paper, particularly inside a series, e.g. a drawing on A3 may be enlarged to A2 or reduced to A4.

The U.S. customary "A-size" corresponds to "alphabetic character" size, and "B-size" corresponds to "ledger" or "tabloid" size. At that place were also one time British paper sizes, which went by names rather than alphanumeric designations.

American Club of Mechanical Engineers (ASME) ANSI/ASME Y14.i, Y14.2, Y14.3, and Y14.v are commonly referenced standards in the U.Due south.

Technical lettering [edit]

Technical lettering is the process of forming letters, numerals, and other characters in technical drawing. It is used to depict, or provide detailed specifications for an object. With the goals of legibility and uniformity, styles are standardized and lettering power has footling relationship to normal writing ability. Engineering drawings use a Gothic sans-serif script, formed by a series of short strokes. Lower example letters are rare in almost drawings of machines. ISO Lettering templates, designed for use with technical pens and pencils, and to accommodate ISO newspaper sizes, produce lettering characters to an international standard. The stroke thickness is related to the grapheme height (for example, two.5mm high characters would have a stroke thickness - pen pecker size - of 0.25mm, 3.5 would use a 0.35mm pen and so forth). The ISO graphic symbol set (font) has a seriffed one, a barred seven, an open four, half-dozen, and nine, and a circular topped 3, that improves legibility when, for case, an A0 drawing has been reduced to A1 or even A3 (and maybe enlarged back or reproduced/faxed/ microfilmed &c). When CAD drawings became more popular, especially using US American software, such equally AutoCAD, the nearest font to this ISO standard font was Romantic Simplex (RomanS) - a proprietary shx font) with a manually adjusted width factor (over ride) to make information technology wait as near to the ISO lettering for the drawing board. Notwithstanding, with the closed four, and arced six and nine, romans.shx typeface could be hard to read in reductions. In more than recent revisions of software packages, the TrueType font ISOCPEUR reliably reproduces the original drawing lath lettering stencil fashion, however, many drawings have switched to the ubiquitous Arial.ttf.

Conventional parts (areas) [edit]

Title cake [edit]

Every engineering drawing must accept a title block.^[x] ^[11] ^[12]

The title cake (T/B, TB) is an area of the cartoon that conveys header-type information about the drawing, such as:

Cartoon championship (hence the name "championship block")
Drawing number
Part number(s)
Proper name of the design activity (corporation, government bureau, etc.)
Identifying code of the pattern activity (such as a Muzzle code)
Accost of the blueprint action (such as city, state/province, country)
Measurement units of the drawing (for case, inches, millimeters)
Default tolerances for dimension callouts where no tolerance is specified
Boilerplate callouts of general specs
Intellectual belongings rights warning

ISO 7200 specifies the information fields used in title blocks. Information technology standardizes eight mandatory data fields:^[13]

Title (hence the name "title block")
Created by (proper name of draughtsman)
Approved by
Legal owner (name of company or organization)
Certificate blazon
Drawing number (same for every sheet of this certificate, unique for each technical document of the organization)
Sheet number and number of sheets (for example, "Sail 5/7")
Date of issue (when the drawing was made)

Traditional locations for the title block are the bottom correct (most usually) or the top correct or center.

Revisions cake [edit]

The revisions block (rev cake) is a tabulated list of the revisions (versions) of the drawing, documenting the revision control.

Traditional locations for the revisions block are the top right (most commonly) or adjoining the title block in some fashion.

Next assembly [edit]

The adjacent assembly block, often also referred to as "where used" or sometimes "effectivity cake", is a listing of higher assemblies where the product on the electric current cartoon is used. This block is ordinarily establish adjacent to the title block.

Notes listing [edit]

The notes listing provides notes to the user of the drawing, conveying any data that the callouts within the field of the drawing did non. It may include full general notes, flagnotes, or a mixture of both.

Traditional locations for the notes list are anywhere forth the edges of the field of the drawing.

General notes [edit]

Full general notes (G/N, GN) apply generally to the contents of the drawing, as opposed to applying merely to certain function numbers or certain surfaces or features.

Flagnotes [edit]

Flagnotes or flag notes (FL, F/N) are notes that apply only where a flagged callout points, such as to particular surfaces, features, or office numbers. Typically the callout includes a flag icon. Some companies call such notes "delta notes", and the note number is enclosed inside a triangular symbol (similar to uppercase alphabetic character delta, Δ). "FL5" (flagnote 5) and "D5" (delta note 5) are typical ways to abbreviate in ASCII-simply contexts.

Field of the cartoon [edit]

The field of the cartoon (F/D, FD) is the main torso or main area of the drawing, excluding the title block, rev cake, P/50 and then on

List of materials, bill of materials, parts list [edit]

The listing of materials (50/M, LM, LoM), bill of materials (B/M, BM, BoM), or parts list (P/50, PL) is a (usually tabular) listing of the materials used to make a part, and/or the parts used to make an assembly. It may incorporate instructions for heat treatment, finishing, and other processes, for each part number. Sometimes such LoMs or PLs are separate documents from the drawing itself.

Traditional locations for the LoM/BoM are above the title block, or in a split document.

Parameter tabulations [edit]

Some drawings call out dimensions with parameter names (that is, variables, such a "A", "B", "C"), then tabulate rows of parameter values for each part number.

Traditional locations for parameter tables, when such tables are used, are floating near the edges of the field of the cartoon, either about the title cake or elsewhere along the edges of the field.

Views and sections [edit]

Each view or department is a separate set of projections, occupying a contiguous portion of the field of the drawing. Normally views and sections are chosen out with cross-references to specific zones of the field.

Zones [edit]

Frequently a drawing is divided into zones by an alphanumeric grid, with zone labels along the margins, such as A, B, C, D up the sides and 1,2,iii,4,v,six along the pinnacle and bottom.^[14] Names of zones are thus, for instance, A5, D2, or B1. This feature greatly eases discussion of, and reference to, item areas of the cartoon.

Abbreviations and symbols [edit]

As in many technical fields, a wide array of abbreviations and symbols take been developed in engineering drawing during the 20th and 21st centuries. For example, cold rolled steel is oft abbreviated as CRS, and bore is often abbreviated as DIA, D, or ⌀.

Near engineering drawings are linguistic communication-independent—words are confined to the title cake; symbols are used in place of words elsewhere.^[15]

With the advent of reckoner generated drawings for manufacturing and machining, many symbols have fallen out of common utilize. This poses a problem when attempting to interpret an older manus-drawn document that contains obscure elements that cannot be readily referenced in standard didactics text or control documents such every bit ASME and ANSI standards. For example, ASME Y14.5M 1994 excludes a few elements that convey disquisitional information as contained in older US Navy drawings and shipping manufacturing drawings of Earth War two vintage. Researching the intent and meaning of some symbols can prove hard.

Example [edit]

Instance mechanical cartoon

Here is an instance of an engineering cartoon (an isometric view of the same object is shown to a higher place). The different line types are colored for clarity.

Black = object line and hatching
Red = hidden line
Blue = center line of piece or opening
Magenta = phantom line or cut aeroplane line

Exclusive views are indicated by the direction of arrows, as in the instance right side.

Legal instruments [edit]

An engineering science drawing is a legal certificate (that is, a legal musical instrument), because it communicates all the needed information about "what is wanted" to the people who will expend resources turning the idea into a reality. It is thus a part of a contract; the buy order and the cartoon together, as well as whatsoever ancillary documents (engineering change orders [ECOs], called-out specs), plant the contract. Thus, if the resulting product is wrong, the worker or manufacturer are protected from liability as long as they have faithfully executed the instructions conveyed past the drawing. If those instructions were wrong, it is the fault of the engineer. Because manufacturing and structure are typically very expensive processes (involving large amounts of uppercase and payroll), the question of liability for errors has legal implications.

Relationship to model-based definition (MBD/DPD) [edit]

For centuries, engineering cartoon was the sole method of transferring information from pattern into industry. In recent decades another method has arisen, called model-based definition (MBD) or digital product definition (DPD). In MBD, the information captured by the CAD software app is fed automatically into a CAM app (computer-aided manufacturing), which (with or without postprocessing apps) creates code in other languages such as G-lawmaking to be executed by a CNC motorcar tool (calculator numerical command), 3D printer, or (increasingly) a hybrid machine tool that uses both. Thus today it is oft the case that the data travels from the mind of the designer into the manufactured component without having ever been codified by an technology drawing. In MBD, the dataset, not a drawing, is the legal musical instrument. The term "technical data package" (TDP) is now used to refer to the consummate parcel of information (in one medium or some other) that communicates information from pattern to production (such every bit 3D-model datasets, engineering drawings, engineering change orders (ECOs), spec revisions and addenda, and then on).

Information technology still takes CAD/CAM programmers, CNC setup workers, and CNC operators to practice manufacturing, as well as other people such as quality assurance staff (inspectors) and logistics staff (for materials handling, aircraft-and-receiving, and front part functions). These workers ofttimes use drawings in the course of their work that have been produced from the MBD dataset. When proper procedures are beingness followed, a articulate chain of precedence is e'er documented, such that when a person looks at a drawing, s/he is told by a note thereon that this drawing is non the governing instrument (because the MBD dataset is). In these cases, the drawing is still a useful document, although legally it is classified as "for reference just", pregnant that if any controversies or discrepancies ascend, it is the MBD dataset, not the drawing, that governs.

Meet also [edit]

Architectural drawing
B. Hick and Sons – Notable collection of early locomotive and steam engine drawings
CAD standards
Descriptive geometry
Certificate management system
Applied science cartoon symbols
Geometric tolerance
ISO 128 Technical drawings – General principles of presentation
calorie-free plot
Linear scale
Patent drawing
Scale rulers: architect'due south scale and engineer's scale
Specification (technical standard)
Structural cartoon

References [edit]

^ ^a ^b Yard. Maitra, Gitin (2000). Practical Engineering Drawing. 4835/24, Ansari Road, Daryaganj, New Delhi - 110002: New Age International (P) Express, Publishers. pp. 2–5, 183. ISBN81-224-1176-2. {{cite book}}: CS1 maint: location (link)
^ ^a ^b Rolt 1957, pp. 29–thirty.
^ French & Vierck 1953, pp. 99–105
^ ^a ^b ^c French 1918, p. 78.
^ ^a ^b ^c French & Vierck 1953, pp. 111–114
^ French & Vierck 1953, pp. 97–114
^ French & Vierck 1953, pp. 108–111
^ French & Vierck 1953, p. 102.
^ Bertoline, Gary R. Introduction to Graphics Communications for Engineers (4th Ed.). New York, NY. 2009
^ The states Bureau of Naval Personnel. "Engineering Aid 1 & C.". 1969. p. 188.
^ Andres G. Embuido. "Engineering Aid i & C". 1988. p. 7-10.
^ "Farm Planners' Engineering science Handbook for the Upper Mississippi Region". 1953. p. ii-5.
^ Farhad Ghorani. "Title Cake". 2015.
^ Paul Munford. "Technical cartoon standards: Grid reference frame".
^ Brian Griffiths. "Engineering science Drawing for Manufacture". 2002. p. 1 and p. 13.

Bibliography [edit]

French, Thomas E. (1918), A manual of engineering science cartoon for students and draftsmen (second ed.), New York, New York, Us: McGraw-Hill, LCCN 30018430. : Engineering science Cartoon (book)
French, Thomas E.; Vierck, Charles J. (1953), A manual of engineering science drawing for students and draftsmen (8th ed.), New York, New York, USA: McGraw-Hill, LCCN 52013455. : Engineering Drawing (book)
Rolt, L.T.C. (1957), Isambard Kingdom Brunel: A Biography, Longmans Green, LCCN 57003475.

External links [edit]

Examples of cubes drawn in different projections
Animated presentation of drawing systems used in technical drawing (Flash animation) Archived 2011-07-06 at the Wayback Automobile
Design Handbook: Engineering science Drawing and Sketching, past MIT OpenCourseWare

brooksbuffe1981.blogspot.com

Source: https://en.wikipedia.org/wiki/Engineering_drawing