ARCH GRAPHICS PART 2 SEM 1

Why are multiple views required in orthographic projection

• To show all dimensions and details.

• To represent hidden and visible features.

• To avoid misunderstanding.

• To provide complete information about the object.

projection plane

• An imaginary flat surface.

• The view of an object is projected on it.

types of projection plane

• Vertical plane.

• Horizontal plane.

• Profile plane.

vertical plane view

horizontal plane

profile plane

• Front view/ elevation.

top view

side view

two advantages of orthographic projection.

• Accurate representation of dimensions.

• Clear communication of technical information.

principle of orthographic projection

• Based on projecting imaginary lines called projectors.

• Projectors are parallel to each other.

• Projectors are perpendicular to the projection plane.

orthographic drawing importance

• Provides accurate dimensions and proportions.

• Guides construction.

• Aids communication among architects, engineers, and contractors.

• Forms essential professional documentation.

front view (elevation) show

• Shows height and width.

• Represents major features.

• Shows the appearance of the object.

How is the top view obtained and what does it show?

• Obtained by looking at the object from above.

• Shows length and width.

• Represents the layout of the object.

What does the side view show and why is it important?

• Shows height and length.

• Reveals side details.

• Completes the description of the object.

an ellipse in geometric terms

• A closed curve.

• Has two fixed points called foci.

• Sum of distances from any point on the curve to the two foci remains constant.

parabola eg

• Satellite dish.

• Reflector.

hyperbola

• A curve with two fixed points called foci.

• The absolute difference of distances from any point to the two foci remains constant.

vanishing point in perspective drawing?

• A point on the horizon line.

• Receding parallel lines appear to meet there.

horizon line represent in perspective drawing

• Represents the eye level of the observer.

• Contains the vanishing points.

development of surfaces

• Process of unfolding a 3D object.

• Converts it into a flat 2D pattern.

• Done without distortion.

angle between two isometric axes

• 120°

three advantages of isometric drawings

• Represents 3D objects on a 2D surface.

• Provides better visualization.

• Makes objects easy to interpret.

isometric projection show

• Shows length, width, and height simultaneously.

• Uses three principal isometric axes.

• Axes are equally inclined to each other

use of isometric scale

• Converts true lengths into isometric lengths.

• Maintains accurate dimensions.

• Ensures proper proportion.

three isometric axes?

• Vertical axis.

• Left isometric axis – 30° to horizontal.

• Right isometric axis – 30° to horizontal.

first step in converting an orthographic view into an isometric view

• Study the front view.

• Study the top view.

• Study the side view carefully.

Orthographic Drawing:

• Uses multiple 2D views.

• Provides accurate technical and construction information.

• Easier for direct measurement.

Isometric Drawing:

• Shows a 3D object in a single pictorial view.

• Provides better visualization.

• Easier for understanding the overall shape.

pictorial projection

• Represents a 3D object on a 2D drawing sheet.

• Shows length, width, and height in a single view.

three types of pictorial projection.

• Isometric projection.

• Oblique projection.

• Perspective projection.

Cavalier Projection: and Cabinet Projection:

• Depth shown at full scale.

• Object may appear elongated in depth.

• Depth shown at half scale.

• Gives a more realistic appearance.

characterizes oblique projection

• One face is drawn in true shape and size.

• Depth is represented by receding lines.

• Receding lines are commonly drawn at 45°.

• Easy to construct and understand.

one-point perspective?

• Uses one vanishing point.

• Vanishing point lies on the horizon line.

• Receding parallel lines converge toward one point.

• Used when the front face directly faces the observer.

two-point perspective

• Uses two vanishing points.

• Both vanishing points lie on the horizon line.

• Receding lines converge toward two separate points.

• Used when an object is viewed at an angle.

station point in perspective drawing

• Position from which the observer views the object.

foreshortening in perspective drawing?

• Apparent shortening of objects or dimensions.

• Occurs due to perspective and distance from the observer.

What does perspective drawing help achieve in architectural graphics?

• Realistic representation.

• Better visualization.

• Easy understanding of buildings and spaces.

• Effective presentation to clients.

line of intersection

• Common boundary where two solids meet or penetrate each other.

• Important for accurate fabrication.

• Useful in construction.

prism

• A solid with two equal and parallel polygonal bases.

• Bases are connected by lateral faces.

pyramid

• A solid with a polygonal base.

• Has triangular faces.

• Faces meet at a common point called the apex.

lateral surface

• Side surface of a solid.

• Excludes the bases.

• In a prism or cylinder, it excludes the top and bottom bases.

two applications of development of surfaces

• Sheet metal work – ducts, tanks, and containers.

• Architectural models – building and roof models.

intersection of surfaces importance

• Shows where two solids meet.

• Provides accurate cutting lines.

• Helps in fabrication and construction.

• Reduces construction errors.

• Used in pipes and ducts.