MECHANICAL DRAWINGMECHANICAL DRAWING

Why do we draw?Why do we draw?

To communicate!!!To communicate!!!

Why does it matter?Why does it matter?What’s the use of a great What’s the use of a great idea if you cant convey it to idea if you cant convey it to any one else.any one else.

No one is an expert at No one is an expert at everything, so we must everything, so we must collaborate to reach a collaborate to reach a common goal.common goal.

Communication with Communication with DrawingDrawing

(things to consider)(things to consider)Subject – what you are trying to

convey (Process, structure, function,

material, etc….)

Audience – who you are communicating with

(designer, client, manager, public, other engineers)

Types of Mechanical Types of Mechanical DrawingDrawingDrawing types we will explore

today◦Sketches◦Isometric Drawings◦Orthographic Projections

When is a sketch useful?When is a sketch useful?

Think about◦What (subject)◦Who (audience)

SketchinSketchingg

– – look and feellook and feel

SketchiSketchingng

– – to show to show processprocess

SketchinSketchingg

– – to explore formto explore form

When is a technical drawing When is a technical drawing useful?useful?

Think about◦What (subject)◦Who (audience)

Technical Drawing - Technical Drawing - IsometricIsometric

Technical Drawing – Technical Drawing – Orthographic Orthographic

Technical Drawing – Technical Drawing – Assembly sectionAssembly section

Technical Drawing – More Technical Drawing – More SectionsSections

Isometric DrawingIsometric Drawing

Isometric DrawingIsometric Drawing

Isometric DrawingIsometric Drawingfront corner is

centered and vertical

bottom edges slant up at a 30 degree angle from horizontal

(You should be viewing 3 of the 6 faces of a cube)

30° 30°

ISOMETRIC DRAWINGISOMETRIC DRAWINGheight (“vertical”) lines are

always drawn vertically in at their true (or scaled) length

width and depth (“horizontal”) lines are drawn 30 degrees from the horizontal at their true (or scaled) length

all lines parallel to the height, width or depth are at their true (or scaled) length

lines not parallel to these axes are not drawn at their true length

height

width depth

Isometric Drawing - Isometric Drawing - DimensionsDimensions

Isometric Drawing - Isometric Drawing - DimensionsDimensions

Identify line to dimension

Isometric Drawing - Isometric Drawing - DimensionsDimensions

Draw extension lines

Isometric Drawing - Isometric Drawing - DimensionsDimensions

Draw dimension lines

Isometric Drawing - Isometric Drawing - DimensionsDimensions

draw as many dimensions as you would need to make the part (no more no less)

did anyone have an object did anyone have an object that couldn’t be fully that couldn’t be fully expressed with a single expressed with a single isometric drawing?isometric drawing?

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

Isometric Drawing

Orthographic Projection

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC PROJECTIONORTHOGRAPHIC PROJECTION

ORTHOGRAPHIC DRAWING – ORTHOGRAPHIC DRAWING – PLANNING PLANNING

what is the minimum number of views required to capture every object feature? often the answer is three, but it could be less or more!

what is the best way to lay out these drawings ◦ best use of paper, should drawings be scaled up or

down?we will be dimensioning drawings, so

leave enough space around each view to add dimensions

think about the order of inking to avoid smudging

ORTHOGRAPHIC DRAWING – ORTHOGRAPHIC DRAWING – LINEWEIGHTS AND STYLESLINEWEIGHTS AND STYLES thick continuous line – used for

visible edges and outlines

thin continuous line – hatching, short center lines, dimensions or projection lines

thin dash-dot line – center lines, to identify the center of a circle or a line of symmetry

thin dashed line – used for important hidden detail, such a hole in a solid or a wall thickness

How do I bring this to the How do I bring this to the classroom??????classroom??????Use sketching for general design,

planning and idea sharing◦Look and feel◦Form ◦process

Use technical drawing for final details such as assembly or part drawings for fabrication◦Isometric◦Orthographic◦Assembly