INTRO TO DESIGN] technical drawing types

Why are isometric and axonometric projection more useful for functional drawings rather than perspective drawings?

- Isometric and axonometric drawings use parallel projection, which means objects remain at the same size, no matter how far away they are - This makes them more useful for functional drawings that are used to explain how something works, whereas perspective drawings are typically used to give a more sensory idea of an object or space.

points to be considered when drawing orthographic views

- dimensions which are parallel to the direction of viewing will not be seen - edges which are parallel to the direction of viewing are seen as points - surfaces which are parallel to the direction of viewing are seen as lines - visible edges and intersections are shown by object lines - hidden edges are shown by dashed lines - the center lines of the symmetrically curved parts like cylinders etc. should be clearly shown

A pictorial drawing of an object that creates a sense of depth through the use of a vanishing point is called a(n):

1-Point Perspective

The edges of a cube in isometric projection make angles of this many degrees with each other:

120

In an isometric drawing, ________ axes are used as guidelines to mark object measurements

3

Which triangle should you use when creating an isometric projection?

30-60-90 triangle

Which triangle should you use when creating an axonometric projection?

45-45-90 triangle

The appropriate angle(s) used to draw the axes on an orthographic projection drawing are:

90 & 180

What are axonometric and isometric projections used for in real life?

Axonometric and isometric projections are used for technical drawings in real life such as designs of houses, floor plans, certain designs for a specific product, etc.

Do the axonometric projections have to be drawn at a 45 degree angle or can it be a different one?

Axonometric drawings do not have to be drawn at 45 degree angles, but the x and y axes must be orthogonal (at 90 degrees to each other)

Are axonometric and isometric drawings drawn to scale?

Both axonometric and isometric projections are drawn to scale. The difference is that axonometric projections have accurate angles, and isometric projections do not.

Why are isometric drawings still drawn?

Sometimes the 30 degree angle of the isometric drawings are able to compensate for the lack of visual distortion when axonometric projections are drawn

projection

a figure formed when various points on the contour of an object are "thrown forward" onto a plane by means of straight lines or visual rays; flattens the object but still allows the drawing to maintain accurate dimensions

orthographic projection

a method of projection in which an object is depicted or a surface mapped using parallel lines to project its shape onto a plane; 2D views for a 3D object

isometric drawing

a type of 3D drawing that is set out using 30-degree angles; the three coordinate axes appear equally foreshortened and the angle between any two of them is 120 degrees; drawn at 30 degrees, less distorted but requires the plan to be redrawn at the 30 degree angle

axonometric projection

a type of projection used for creating a pictorial drawing of an object, where the object is rotated around one or more of its axes to reveal multiple sides; do not have vanishing points like the conventional perspective drawings; all lines on a common axis are drawn as parallel; drawn at 45 degrees, a bit distorted whereby horizontal planes get more emphasis, easier to create because the plan does not need to be redrawn

In an axonometric view, which lines will be drawn exactly to scale or measurement?

all of them

In orthographic projection, an object is represented by one or more views on different planes which:

are mutually perpendicular projection planes

In orthographic projections, a object is represented by one or more views on different planes which:

are mutually perpendicular projection planes

extension lines

are short, solid lines used to show the limits of dimensions; they may be placed inside or outside the outline of an object; they extend from an outline or surface, but do not touch it​

phantom lines

are thin lines used to show a part of an object that is absent, or indicate an alternate position for the parts of an object

In which of these drawings includes an exact copy of the top orthographic projection of the same object?

axonometric projection

When the receding lines are true length, and the projectors are at 45-degrees to the plane of projection, the drawing is called this:

axonometric projection

In which of these drawings are the X & Y axes orthogonal to each other?

axonometric projection, orthographic projection

how are objects represented in orthographic projections?

by a one or more views on different planes which are perpendicular to each other; gives up to 6 different views (front and back view in the x-direction, top and bottom view in the y-direction, and side views in the z-direction) which are mutually perpendicular.

hidden lines

consist of short evenly spaced dashes that outline hidden or invisible surfaces.

where are axonometric projections used?

construction, engineering, manufacturing, and everyday application such as computer games

Center lines are helpful for interpreting certain 3D objects. Which one of these would benefit most from the inclusion of a center line?

cylinders

Hidden lines represent edges and boundaries that cannot be seen. They are represented by a:

dashed line

what are the different views of orthographic projections?

front, top (plan), side

The front and side views are aligned horizontally and share the same:

height

When an edge is not visible from that view, it is a _____________________ line.

hidden

break line

indicate that a part is broken out or removed either to (1) show more clearly the part or parts that lie directly below the broken out part (2) to reduce the size of the drawing of a long part so that it can be shown on a smaller sheet.​

leaders

indicate the part or area of a drawing to which a number, note, or other reference applies; they are thin, solid lines and usually terminate in a single arrowhead.

orthogonal

involving right angles

A three dimensional view of an object that simulates perspective through foreshortening and accurately conveys measurements along the X, Y, and Z axis is called a(n):

isometric projection

What is the purpose of the 45 degree projection line?

it accurately transfers dimensions from the top view to the side view

center line

marks the center of the object and consist of alternating long and short evenly spaced dashes, with a long dash at each end and short dashes at point of intersection

The reason we do not include the left and right side views in orthographic projections is because they are usually:

mirrow views

Where a curved surface meets a plane, no line is drawn. When a curved surface intersects a plane a(n) ____________is drawn.

object line

parallel projection

objects remain at the same size, no matter how far away they are

A two dimensional view of one side of an object that accurately conveys measurements along two axes (i.e. x & y, or y & z, etc.) is called a(n):

orthographic projection

the glass box theory

projections of the object are made onto the surfaces that make up a box

dimension lines

short, solid lines that indicate the distance between two point on a drawing; they terminate with arrowheads at each end, and are broken to insert dimension

An isometric view would be used to _____.

show a reasonably accurate view of a three-dimensional object

object line

thick, solid lines that outline all surfaces visible to the eye

Isometric and axonometric drawings show _________ of objects.

three dimensions

What is the primary purpose of technical drawings like orthographic projections?

to communicate the accurate details of an idea, plan, or object to some other person

What is the function of the "projectors" (aka projection lines) that are drawn between each view and erased at the end?

to make sure all views are aligned and consistently sized

The top and front views are aligned vertically and share the same:

width