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Engineering Drawing Types My name is Gary and I’d like to welcome you to this lesson on understanding and teaching the principles associated with Engineering Drawing Types.

Purpose Universally accepted Efficient Multi-functional What purposes do engineering drawings serve? ** A variety of engineering drawings are used the world over to communicate pictorial information between individuals. These drawings use commonly accepted formats for view layout and annotations. Use of common formats are a result of the need for individuals from other departments, companies, or even countries to be able to quickly view and understand detailed visual information from any source. ** Well laid out drawings are an efficient means of communication because they provide greater information in less time for everyone involved in the development of a product. Appropriate use of 2D or 3D images, notes, and annotations saves time and money at every step. ** Engineering drawings are also multi-functional in that they can be used simultaneously by all departments in a business such as design, drafting, prototyping, production, or even advertising. Departments don’t necessarily need their own specialized views to be productive in the overall design process.

Basic Engineering Drawing Types Freehand Sketch Orthographic or Multi-view Sketch Pictorial Sketch Oblique Sketch Isometric Sketch Perspective Sketch Generally speaking, engineering drawings can be separated into two types, basic and advanced. These categories are based on the needs of the intended audience and the information the drawings provide. First, let’s identify the basic types of drawings. ** We’ll start with the most common form of communication in the engineering field, freehand sketching. It is the easiest, the quickest, and it requires minimal tools. It can be used any time and anywhere there is a need. ** The next type is the orthographic sketch. These are sometimes called multi-views. They provide a perpendicular or straight-on view of each side of an object. Most drawings will show as many as three sides. ** Pictorial sketches encompass a broad range of layouts that show three sides of an object in one view. ** The 1st type of pictorial is the oblique sketch. Oblique sketches are usually simple to draw, but not the most realistic looking when finished. ** The 2nd type of pictorial is the isometric sketch. Isometric sketches are used often because they are the most accurate as far as dimension, scale, and proportion. ** The last type of basic pictorial is the perspective sketch. This type is more difficult to draw, but is more realistic looking than the others when created correctly.

Freehand Sketch Drawing Add Views as needed Annotations Notes Title Now let’s look at the basic types of engineering drawings. The freehand sketch can be quick, accurate, and detailed if needed. It can be done in most any environment as long as one has a surface to draw on. ** Objects can be displayed in any type of view that shows the details of the design so that others can understand it. Multiple views can be drawn and annotated as needed. A basic sketch would include one or more pictures, ** notes about finishes, materials, or assembly, ** and annotations of the design laid out in an organized fashion. Other items to include would be a ** drawing title, ** the designer’s signature, and ** the date the sketch was created. Initials Date

Orthographic or Multi-view Drawing Top Top Add Notes as needed Dimensions Front Right Side Orthographic or multi-view drawings are usually displayed with one to three views, but can incorporate up to 6 views. Imagine the object placed inside a glass box and then viewed from each side of the box, including the top and bottom. This will show you what each of the six views will look like. The upper right corner of this drawing has a picture of what the object would look like inside a box and what three typical views would look like as they are projected out onto the surface of the box. ** These three standard views of front, ** top, and ** right side are then projected at right angles from each other onto the paper, with the front view usually acting as the base or first view. These views incorporate the three true lengths for height, width, and depth, and are aligned vertically and horizontally to help in grasping visibility and proportion. ** Hidden lines are used to show features that are not visible from that viewpoint, but are added as visual aids. ** Again, don’t forget the other important components such as annotations, ** notes for finish, materials, ** drawing title, author’s name, date, and scale. Hidden Lines Front Title Right Side Scale Your Name

Oblique Pictorial Drawing Full Depth Half Depth Any Standard Angle True length The next type of pictorial view is the oblique. Oblique views are generally easy to draw and understand. ** The front surface of the object is drawn facing the viewer straight on and has true lengths for height **and width. ** The depth is drawn back at a standard angle, usually of 30 or 45 degrees. ** If the object is drawn at what is considered full size and proportion, it is called a cavalier oblique. ** The other type, a cabinet oblique, is drawn just like a cavalier except the depth is drawn at half the proportion so larger objects can fit in a smaller space or if less detail needs to be displayed. Hidden lines are not usually drawn in oblique views. 30 True length

Isometric Pictorial Drawing True Length The isometric pictorials are commonly used because the designer can use true lengths for ** width, ** depth, and ** height. It is also generated automatically by most 3D modeling software. The isometric pictorial is probably the best pictorial for displaying objects in scale and proportion. The width and depth are drawn at 30 degree angles from horizontal, and height is measured vertically. Hidden lines are not typically used in these views. True Length True Length 30 30

1 Point Perspective Pictorial Drawing True Length One-point perspective drawings are pictorials that are easy to draw. They use the concept of convergence on the lines showing depth. ** The front view of the object is facing the viewer straight on and has true lengths for height**and width. ** The lines for depth are drawn so they converge at the vanishing point located somewhere on the horizon line. This convergence of the lines gives the object its perspective as if it is disappearing into the distance. The horizon line, which can be located above or below the ground line, is drawn at the height of the viewer’s eye. The object’s frontal plane appears to rest on the ground line. The lines for depth are not true length and should be stopped where the person drawing the view believes the correct proportion is achieved. There are usually no hidden lines used in one-point perspective views. True Length

2 Point Perspective Pictorial Drawing True Length Two-point perspective pictorial drawings are more difficult to draw than one point, but the outcome is more realistic. ** The only true length is height, which is located on the front corner of the object closest to the viewer. ** There are now two vanishing points located on the horizon line. All of the lines traveling in the width direction converge at the left vanishing point.** The lines for depth converge at the right vanishing point. The lines for width and depth are not true length and can be stopped when the appropriate proportion is achieved. Hidden lines are not used in the two-point perspective pictorial view.

Advanced Engineering Drawings Renderings Auxiliary Sections Assembly Exploded Animation Our second classification of engineering drawings, which we’ll call “Advanced”, are used in combination with the basic drawing types shown previously to give the target audience a better idea of the overall concept and application of a design. ** First on the list are renderings, which can be thought of as pictorial sketches with colors. Colors are used to make the object “pop” from the paper and look more finished or professional. ** Next are auxiliary views, which are used when the object has an inclined surface as part of the general shape. ** Section views are used to show hidden or minute details not seen in other standard views. ** Next are assemblies, which are used to show how a design with multiple parts looks when everything is attached. ** Exploded views appear as if the object has been pulled apart piece by piece. Each part is identified, and trails are used to show locations of each piece. ** An animation can show how parts move in relation to each other or steps in the assembly of an object.

Rendering Pictorial Drawing The rendering is basically a colored view of some type of pictorial. Any type of pictorial view and coloring medium can be used. The intent is to have the design “pop” from the picture and make it more appealing to the viewer. This view is commonly used in advertising or in its intended application to make the design look more finished.

Auxiliary Drawing TLs True Lengths 90 Auxiliary views are displayed when the object to be drawn has an inclined surface as part of the general shape. ** The auxiliary view is drawn perpendicular to the inclined surface ** and shows the details of the surface in true length and shape. ** The surface of the plane can be annotated in the auxiliary view, but the rest of the object is usually of less importance and is not necessarily complete or included. The dimensions should be aligned to the view. Hidden lines are usually not included unless needed for clarity.

Section Drawing Cutting Plane View remaining part from this direction Ortho view of sectioned part Solid Material The next advanced engineering drawing is the section view.** The section view is used to show internal or hidden features which are not clearly seen in other views. It is also used to show minute details which can’t be seen in the regular views because of the small scale of the display. ** A cutting plane line is drawn in the view to be sectioned. This line shows where the object will be cut ** and from what direction the ** remaining part will be viewed. The section view itself uses various line types such as ** diagonal lines to show where and what type of solid material was cut through. Hidden lines are not usually displayed in the actual section view. Removed Part

Assembly Drawing Assembly type drawings encompass any views that show the object after assembly and can be used to show overall dimensions, proportion, color coordination, or how the design fits into its intended application.

Exploded Drawing Balloons Parts List Exploded view drawings are usually pictorial views of all of the parts of a product pulled apart and visible as separate entities. Tweaks and trails are used to show the relationship between parts for location and fit. These drawings can also be used to show the steps of the assembly process.** Balloons reference each part to a parts list **that displays specifications for each part of the assembly. Parts List

Animation Video Animation views are videos of the designs shown in movement. The animations demonstrate how the parts move in relation to each other. **(Link to Exploded Bracket Assembly Video) These views are also commonly used for advertising or to show the steps used to assemble the product.

References: Madsen, D., Folkestad, J., Schertz, K., Shumaker, T., Stark, C., & Turpin, J. (2004). Engineering Drawing and Design (3rd ed.), Albany, NY: Thompson Learning, Inc. / Delmar. Title is blue 44 pt. Arial Text black 24 pt. Arial Refer to APA 5th edition if you have questions regarding citations

Credits: Writer: Gary Platt Content Editor: Sam Cox & Wes Terrell Production Work: CJ Amarosa We would like to thank you for joining us for this lesson on Engineering Drawing Types. We hope it was helpful and your Virtual Academy learning experience was enjoyable.