ENGR-22_Lec-06_AdvanCmd-2.ppt 1 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Bruce Mayer, PE Registered Electrical.

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Presentation transcript:

ENGR-22_Lec-06_AdvanCmd-2.ppt 1 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Bruce Mayer, PE Registered Electrical & Mechanical Engineer Engineering 22 AutoCAD© Advanced Cmds-2

ENGR-22_Lec-06_AdvanCmd-2.ppt 2 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Learning Goals  Use the ACAD “Osap” tools to facilitate point selection  Use ACAD “Grips” to facilitate entity modification  Create and Use ACAD “Blocks”  Create & Modify ACAD “Layers”  Use Geometric Construction to Bisect a Line or an Angle

ENGR-22_Lec-06_AdvanCmd-2.ppt 3 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layers  Probably the most important object property to understand well is the LAYER property.  Experienced AutoCAD users use layers all the time that is why the Object Properties toolbar contains so many layer functions. Layers ToolBarProperties ToolBar

ENGR-22_Lec-06_AdvanCmd-2.ppt 4 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layers Concept  Basically, layers are the computer equivalent of TRACING OVERLAYS on a drawing board  A Drawing can Have MANY Layers Could be up to one for EACH Part  You can control the Visibility, Color and Linetype of layers independently These Three Properties form a ShortHand for line meaning

ENGR-22_Lec-06_AdvanCmd-2.ppt 5 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layer Utility  Layers are effectively a way of ordering a CAD drawing e.g.; You could create a layer called "Construction" and use this for your construction lines. When the drawing is complete, you could simply TURN OFF this layer off so that it can't be seen  Good & Consistent use of layers is the MOST Important aspect of good CAD drawing practice

ENGR-22_Lec-06_AdvanCmd-2.ppt 6 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layer Management  Layers are Typically Defined Based on Some Combination of these Criteria By Line-Type or Line-Usage By Part or Component By Material or Form; e.g. –On a Construction dwg Layers might be defined by Materials: Steel, Wood, Concrete –On a Piping Design Dwg Layers Defined by Fluid: ColdWater, HotWater, NatGas, Sewer –On Landscape Design by main elements: Trees, Scrubs, Grass, FlowerBeds

ENGR-22_Lec-06_AdvanCmd-2.ppt 7 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Standard Lines  Line Patterns Communicate What The Line Represents In The Drawing  Line Patterns Tell You Information Such As Whether The Line Is Hidden, Visible, Or A Centerline  Line Precedence: Visible → Hidden → Center Visible line Hidden line Hatching Centerline Dimension Extension Leader Cutting Plane Viewing Plane Short break Long break Phantom Stitch Chain

ENGR-22_Lec-06_AdvanCmd-2.ppt 8 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layers By Line-Type One FUNCTIONAL Layer

ENGR-22_Lec-06_AdvanCmd-2.ppt 9 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layers by Function Several LineType Layers

ENGR-22_Lec-06_AdvanCmd-2.ppt 10 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Layers by Part or Component

ENGR-22_Lec-06_AdvanCmd-2.ppt 11 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Make A Layer  Let’s Make a New Layer for HIDDEN LINES Color → Red LineType → Hidden (Evenly Spaced Dashes) LineWidth → ACAD default 1.Start at new acad.dwt Drawing 2.Activate Format Layer Dialog Box

ENGR-22_Lec-06_AdvanCmd-2.ppt 12 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Make A Layer cont 3.Click on the New Layer icon 5.Select Color 4.Name the Layer as “Hidden” 6.Pick Red from DB

ENGR-22_Lec-06_AdvanCmd-2.ppt 13 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Make A Layer cont 7.Select Linetype 8.Don’t See the “Hidden” type so click Load → DB Activates the Loaded Linetypes Dialog Box (DB) Find HIDDEN; click OK

ENGR-22_Lec-06_AdvanCmd-2.ppt 14 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Make A Layer cont 9.With Hidden Loaded, Pick it from Select Linetype DB 10.Rt-Click on Status Column and Select Current Click OK

ENGR-22_Lec-06_AdvanCmd-2.ppt 15 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Make A Layer cont 11.Click OK on Last dialog Box  Draw a Pentagon with the Hidden Layer

ENGR-22_Lec-06_AdvanCmd-2.ppt 16 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Draw with Hidden Layer

ENGR-22_Lec-06_AdvanCmd-2.ppt 17 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Draw on Different Layer  Start with “OBJ” layer Draw a Nice Circle  Activate Layer PullDown on the Layers ToolBar  Click on the “DIM” Layer to make it the “Current” Layer

ENGR-22_Lec-06_AdvanCmd-2.ppt 18 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Draw on Different Layer CONT  Layer-Status Window on Layers ToolBar Now shows “DIM” as current  The Heptagon will then Reside on the Current Layer “DIM  Draw a Nice Heptagon Next to the “OBJ” Layered Circle

ENGR-22_Lec-06_AdvanCmd-2.ppt 19 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Entities on Different Layers

ENGR-22_Lec-06_AdvanCmd-2.ppt 20 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Move Entity to Different Layer  Lets Move the Circle to the “PHANTOM” Layer  Click to Circle to activate the Grips  With the Handles Active PullDown the Layer-Status Menu  Click on “PHANTOM”

ENGR-22_Lec-06_AdvanCmd-2.ppt 21 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Move Entity to Different Layer  Deactivate the Grips by Hitting Esc key

ENGR-22_Lec-06_AdvanCmd-2.ppt 22 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics LineType Scale  The distance between Line Dashes does NOT change with the Drawing Scale  Hidden lines?  Pick the TOP one, and Rt-Click to Turn on Properties Menu

ENGR-22_Lec-06_AdvanCmd-2.ppt 23 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics LineType Scale cont  Properties Menu Active  Change Linetype scale to and close Prop Menu  Can Change GLOBALLY with LTSCALE comand

ENGR-22_Lec-06_AdvanCmd-2.ppt 24 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Match Properties Tool  MATCHPROP is a quite convenient tool  Example – Want the Ellipse to be on Same Layer as Heptagon  Click the MatchProp Tool  Click the SOURCE Object

ENGR-22_Lec-06_AdvanCmd-2.ppt 25 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Match Properties Tool cont  Mouse Pointer takes PaintBrush Form  Click Target Object  The Result  MatchProp Invocation  Hit the Esc Key to Deactivate the format Painter

ENGR-22_Lec-06_AdvanCmd-2.ppt 26 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics More Editing Commands  Polyline Edit Can Turn an Object INTO a PLine  Spline Edit  Text Edit

ENGR-22_Lec-06_AdvanCmd-2.ppt 27 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Geometric Construction  Geometric Elements Point –Specifies An Exact Location In Space –Dimensionless Line –Has Length And Direction But No Width –Straight Line  Shortest Distance Between 2 Points Curve –Locus Of Connected Pts That are Not Straight-Collinear  Direction Changes Constantly Plane –A Two Dimensional Slice Of Space –No Thickness (2-D Characteristic)

ENGR-22_Lec-06_AdvanCmd-2.ppt 28 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Geometric Construction  Geometric Elements Closed 2-D elements –Edges May be  Straight Lines → Polygons  Curved Lines → e.g., Circles, Ellipses Surfaces –Do Not Have Thickness –Two Dimensional At Every Point  No mass or volume Solids –3D Forms with Mass & Volume

ENGR-22_Lec-06_AdvanCmd-2.ppt 29 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Construction: Math vs. Engrng  Mathematical Geometric Construction “Allows” Only Two Instruments Straight Edge; i.e., NOT a Ruler/Scale Compass  No MEASUREMENTS Are Made  Engineering Starts with Geometry and Builds for Practical Application Triangles, Circle Templates, Scales, Etc.

ENGR-22_Lec-06_AdvanCmd-2.ppt 30 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Line Perpendicular Bisection  By Compass  By CAD

ENGR-22_Lec-06_AdvanCmd-2.ppt 31 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Angle Bisection  By Compass  By CAD

ENGR-22_Lec-06_AdvanCmd-2.ppt 32 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics All Done for Today The Venerable Drawing Compass

ENGR-22_Lec-06_AdvanCmd-2.ppt 33 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Bruce Mayer, PE Licensed Electrical & Mechanical Engineer Engr/Math/Physics 25 Appendix 

ENGR-22_Lec-06_AdvanCmd-2.ppt 34 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Bruce Mayer, PE Licensed Electrical & Mechanical Engineer Engineering 20 GeometricConstruction

ENGR-22_Lec-06_AdvanCmd-2.ppt 35 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Geometric Elements  A Point  A Line  A Curve  A Plane  Closed 2-D elements  Surfaces  Solids

ENGR-22_Lec-06_AdvanCmd-2.ppt 36 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Point  Specifies An Exact Location In Space Dimensionless –No Height –No Width –No Depth  Always Show With Crossed Lines Do Not Use a “Dot”

ENGR-22_Lec-06_AdvanCmd-2.ppt 37 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Line  Has Length And Direction But No Width  Straight Line  Shortest Distance Between 2 Points The Common Definition of a Line

ENGR-22_Lec-06_AdvanCmd-2.ppt 38 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Line cont.1  May Be Infinite At Least One Point Must Be Specified Direction May Be Specified With A Second Point Or With An Angle A “RAY” is Semi-Infinite (End-Pt & Direction)  May be finite Defined By Two End Points Defined By One End Point, A Length, And Direction

ENGR-22_Lec-06_AdvanCmd-2.ppt 39 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Lines – Special Cases  Two Intersecting Lines Form an ANGLE Symbol =  Measured in –Degrees; 0-360,  36.87° –Radians; 0-2 ,  rad or   Perpendicular Lines Intersect at Equal  s 4, 90° Intersections; Symbol =   Parallel Lines  Lines in a Plane That do Not Intersect Symbol = 

ENGR-22_Lec-06_AdvanCmd-2.ppt 40 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Curve  Locus Of Pts Along A Curve That are Not Collinear  Direction Changes Constantly  Single Curved Lines All Pts On The Curve Lie in A Single Plane  Regular Curve The Distance From A Fixed Point To Any Point On The Curve Is A Constant –e.g., Circle, Arc

ENGR-22_Lec-06_AdvanCmd-2.ppt 41 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Plane  A Two Dimensional Slice Of Space  No Thickness (2-D Characteristic)  Any Orientation Defined By: 3 Points 2 Parallel Lines Line And A Point 2 Intersecting Lines  Appears As A Line When The Direction Of View Is Parallel To The Plane

ENGR-22_Lec-06_AdvanCmd-2.ppt 42 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Closed 2-D Elements (Planar)  Edges May be Straight Lines → Polygons Curved Lines → e.g., Circles, Ellipses  Triangles St-Lines on 3-Sides Part of the Polygon Class Basis of Trigonometry

ENGR-22_Lec-06_AdvanCmd-2.ppt 43 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics 4-Sides Polygons  Quadrilateral  Straight-Line Bounded on Four Sides Important Special Cases –Rectangle –Square

ENGR-22_Lec-06_AdvanCmd-2.ppt 44 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Regular Polygons  Regular Polygons Have Equal Angles And Equal Sides  Often Created And Described By Inscribing Them In A Circle Circumscribing Them About A Circle

ENGR-22_Lec-06_AdvanCmd-2.ppt 45 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Circle  A Circle Is A Closed Curve, All Points Of Which Are Equally Distant From The Center  Primary Descriptors Radius, R Diameter, D = 2R Circumference, C = 2  R =  D

ENGR-22_Lec-06_AdvanCmd-2.ppt 46 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Most Important Closed Elements  Circle Nature’s Favorite Shape –Minimum Energy Geometry  Sharp Angles Exist in Nature (e.g. Crystal Structures), but Not many Easy to Fabricate by “Spinning” –e.g., Drill, Lathe, Pottery Wheel, etc  Rectangle Simplest “Human-Made” Form –Fabricate With Rectilinear motion (XY-Table)

ENGR-22_Lec-06_AdvanCmd-2.ppt 47 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Surface  Does Not Have Thickness  Two Dimensional At Every Point No mass No volume  Generally 3-Dimensional May Be Planar  May Be Used To Define The Boundary Of A 3-D Object Defines the “Skin” of the Object

ENGR-22_Lec-06_AdvanCmd-2.ppt 48 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Solids  3D Forms with Mass & Volume

ENGR-22_Lec-06_AdvanCmd-2.ppt 49 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Construction: Math vs. Engrng  Mathematical Geometric Construction “Allows” Only Two Instruments Straight Edge; i.e., NOT a Ruler/Scale Compass  No MEASUREMENTS Are Made  Engineering Starts with Geometry and Builds for Practical Application Triangles, Circle Templates, Scales, Etc.

ENGR-22_Lec-06_AdvanCmd-2.ppt 50 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Instrumental Drawing Tips  GEOMETRIC-CONSTRUCTION And PROJECTIONS Form the Heart of Instrumental and CAD Drawing  Accuracy is Critical Suggest Making “GuideLines” with 4H-6H Lead –Draw Construction/Guide Lines Very Lightly  Later Fill-in “Drawing Lines” at Standard Darkness 2X-Check Measurements

ENGR-22_Lec-06_AdvanCmd-2.ppt 51 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Line Bisection  Preferred Methods → More Accurate Compass or Triangle  Scaling OK → Quick; Less Accurate HORIZONTAL & VERTICAL Lines

ENGR-22_Lec-06_AdvanCmd-2.ppt 52 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Angles – Bisect, Transfer  Protractors Can Be Cumbersome for These Tasks Use the Compass-Based Techniques

ENGR-22_Lec-06_AdvanCmd-2.ppt 53 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Parallel Lines (||)  Compass Techniques Are Accurate But Cumbersome → Use Sliding Triangles  ||-Line Thru a Given Pt  Line || to Given Distance CD

ENGR-22_Lec-06_AdvanCmd-2.ppt 54 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Divide Line into Equal Parts  Division by the Higher Prime Numbers (e.g., 7, 13) Results in Irrational Values Very Difficult To Scale Accurately  Use “Tilted Scale” With Integral Values

ENGR-22_Lec-06_AdvanCmd-2.ppt 55 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Proportional Division  Again, Scaling Can Be Inaccurate  Since Drawing Vertical & Horizontal Lines Is Most Convenient, Method (a) is Preferred (Others are Fine) Ratio: 2:3:4

ENGR-22_Lec-06_AdvanCmd-2.ppt 56 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Drawing Perpendiculars (  )  Compass Methods Most Accurate  Sliding Triangles Preferred Due to Speed with Acceptable Accuracy Rt-Triangle is Useful In Construction –Most Convenient for Tape-Measures Pt-P Off line Pt-P On line

ENGR-22_Lec-06_AdvanCmd-2.ppt 57 Bruce Mayer, PE Engineering 22 – Engineering Design Graphics Triangles  It’s Very Difficult to Close a Triangle WithOUT Using the Compass  Swing-Arcs Ensures a Nicely Closed 