AutoCAD 3D Fundamentals Engineering 22 AutoCAD 3D Fundamentals Bruce Mayer, PE Licensed Electrical & Mechanical Engineer BMayer@ChabotCollege.edu

Learning Goals Draw Right Hand Coord System Distinguish between ACAD World CoOrd System (WCS) and User CoOrd Systems (UCS) In ACAD Create and Save and UCS’s Use UCS, elev, and thickness to draw “Extruded” Shapes Use ACAD ViewPorts to Show Orthographic Views from a 3D View

AutoCAD CoOrdinate Systems AutoCAD system maintains a 3D database World Coordinate System X,Y as top (plan) view (civil engineering) Z axis vertical User Coordinate System (UCS) may be aligned with features (name and save) Icon shows current coordinate system

RIGHT Hand CoOrd Systems The CoOrd TriAd is Defined by Your RIGHT Hand → Rt-Hand Rule

Right-Hand Rule Thumb points in the positive x direction Index finger points in the positive y direction Middle finger points in the positive z direction Used to define positive rotation Point thumb in the positive direction along the axis which is perpendicular to the plane of rotation The fingers point in the direction of positive rotation

World Coordinate System The Default 3D Coord Base System is the World Coordinate System, or WCS The Orientation of the WCS relative to the Default Screen We Can find the WCS Icon in the Lower Left

WCS Note that the “Z” Axis for the WCS comes OUT of the Screen Looking “Straight Down” on the Z-axis gives us the familiar “Plan View” 2D Orthographic Drawing System World Co-ordinate System Set to Origin - Origin is OFF screen World Co-ordinate System Set to Origin - Icon displayed AT origin

View Point Can Change the “Point of View”, or Viewpoint, for the Object in 3 Ways WCS View Point

Changing ViewPoints By PullDown Menu

The “SW” IsoMetric

View Command view brings up ViewPoint Dialog Box

The ViewPoint ToolBar Can Also Change ViewPoint with The “View” ToolBar To RETURN to PLAN View in the WCS Use the PullDown Menu

Local (User) Coord Systems The WCS can be MODIFIED to fit the needs of the USER For Drawing in Orientations OTHER than the Plan View Modify the WCS to a UCS: Define new origin (with existing axes) Rotate existing Coordinate System about X, Y, or Z Axis Define new origin and axes (3-Point option) NAME and SAVE the UCS

User (Local) CoOrd Systems WCS → (1,4,-3) UCS → (3, 3.5, 0) UCS WCS + (1,4,-0) (4,1,-3) + (4,1,0)

Making a UCS by Command Ln Specify an Origin UCS /New /orthoGraphic (specify the origin relative to the current coordinate system) Reorient the axes UCS /New /Zaxis (choose the direction of the Z axis) /3point (choose the origin and the positive X and Y direction) /Z (specify the angle of rotation about the Z axis) Save and Restore the UCS UCS /Save and UCS /Restore

Example → Make a UCS Make a UCS Called “slant” using the CoOrd from 2-Slides Back Know origin and pts in WCS space Start w/ WCS Use UCS → NEW → 3Point Commands Invoke UCS/3p to Set Origin to (4,1,0) Set Points to Define X & Y Axes

Result → Make a UCS View from WCS Plan View Invoke UCS/3p to Set Origin to (4,1,0) x-Axis INTO Paper

Save and Use New UCS Give the New UCS a NAME with the Save command Change to Plan View for UCS Command: ucs Current ucs name: *NO NAME* Enter an option [New/Move/orthoGraphic/Prev/Restore/Save/Del/Apply/?/World] <World>: s Enter name to save current UCS or [?]: slant

Plan View in “slant” UCS Plumbing Fitting Shows Up as Edge View → Not too interesting Lets Make “twist” UCS by ROTATING the WCS

Command History for twist Command: ucs Current ucs name: *WORLD* Enter an option [New/Move/orthoGraphic/Prev/Restore/Save/Del/Apply/?/World] <World>: n Specify origin of new UCS or [ZAxis/3point/OBject/Face/View/X/Y/Z] <0,0,0>: x Specify rotation angle about X axis <90>: 41 Command: UCS Current ucs name: *NO NAME* Specify origin of new UCS or [ZAxis/3point/OBject/Face/View/X/Y/Z] <0,0,0>: y Specify rotation angle about Y axis <90>: 67 Specify origin of new UCS or [ZAxis/3point/OBject/Face/View/X/Y/Z] <0,0,0>: z Specify rotation angle about Z axis <90>: 13 <World>: s Enter name to save current UCS or [?]: twist Use command TEXTSCR to show command history in a separate window

Draw Heptagon in twist UCS Put Dwg-Space into Plan View for twist Draw a Heptagon in twist-space

Drawing in UCS Can ONLY Draw in the CURRENT UCS WCS Current → PLAN View To Change UCS Use the Dialog Box Invoked by PullDown Tools → Named UCS

Elev and Thickness Time For Live Demo 300 high The Elev Command Can Be used to “Extrude” Basic Shapes Demonstrate by Constructing the Object at Left Time For Live Demo

EX14-14 → 1 Start new Dwg using acadiso.dwt Locate and draw the 50x50 “bases” for the “towers” Change to SE Isometric view Construct the Tower Using Elev Thickness line

EX14-14 → 3 Command: _-view Enter an option [?/Categorize/lAyer state/Orthographic/Delete/Restore/Save/Ucs/Window]: _seiso Regenerating model. Command: elev Specify new default elevation <0.0000>: Specify new default thickness <0.0000>: 300 Command: l LINE Specify first point: Specify next point or [Undo]: Specify next point or [Close/Undo]: Specify next point or [Close/Undo]: c Command: Command: z ZOOM Specify corner of window, enter a scale factor (nX or nXP), or [All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: e Regenerating model.

EX14-14 → 4 Move UCS to Top Corner by Picking Point w/ Mouse Draw CrossBar using Osnap Elev Thickness Enter an option [New/Move/orthoGraphic/Prev/Restore/Save/Del/Apply/?/World] <World>: n Specify origin of new UCS or [ZAxis/3point/OBject/Face/View/X/Y/Z] <0,0,0>:

EX14-14 → 5 Commands to Construct CrossBar Command: z ZOOM Specify corner of window, enter a scale factor (nX or nXP), or [All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: w Specify first corner: Specify opposite corner: Command: elev Specify new default elevation <0.0000>: Specify new default thickness <300.0000>: 50 Command: l LINE Specify first point: Specify next point or [Undo]: Specify next point or [Close/Undo]: Specify next point or [Close/Undo]: c

EX14-14 → 6 Move and Rotate UCS so that the XY plane Resides on the inside of the 1st tower Z-axis extend toward 2nd Tower The Command History (pts Picked) Command: ucs Current ucs name: *NO NAME* Enter an option [New/Move/orthoGraphic/Prev/Restore/Save/Del/Apply/?/World] <World>: n Specify origin of new UCS or [ZAxis/3point/OBject/Face/View/X/Y/Z] <0,0,0>: 3p Specify new origin point <0,0,0>: Specify point on positive portion of X-axis <1.0000,50.0000,0.0000>: Specify point on positive-Y portion of the UCS XY plane <0.0000,51.0000,0.0000>:

EX14-14 → 7 Draw Connecting Cylinder using elev → 0 Thickness → 110 Circle → Ø50 EX14-14 → 7 Use xline and offset to Locate Cyl Ctr

EX14-14 → 8 Expand Limits, zoom → 1 to fit

EX14-14 → 9 Commands to Construct OrthoViewPorts Command: limits Reset Model space limits: Specify lower left corner or [ON/OFF] <0.0000,0.0000>: Specify upper right corner <210.0000,330.0000>: 210,360 Command: z ZOOM Specify corner of window, enter a scale factor (nX or nXP), or [All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: 1 Command: -view Enter an option [?/Categorize/lAyer state/Orthographic/Delete/Restore/Save/Ucs/Window]: o Enter an option [Top/Bottom/Front/BAck/Left/Right]<Top>: r Regenerating model.

All Done for Today The AME and Bonus Tol. 3D Orbit Command http://www.tec-ease.com/tips/august-97.htm Calculating Additional Tolerance Permitted when a Position Tolerance is Modified at MMC.  An additional tolerance, often called Bonus tolerance, is permitted when a position tolerance is modified at maximum material condition (MMC) and the actual mating envelope of the feature has departed from the MMC.  In these illustrations, the part is black and the actual mating envelope is red.

Licensed Electrical & Mechanical Engineer BMayer@ChabotCollege.edu Engr/Math/Physics 25 Appendix  Time For Live Demo Bruce Mayer, PE Licensed Electrical & Mechanical Engineer BMayer@ChabotCollege.edu

Rotate Axis OnScreen

EX14-5

EX14-5 → zoom → 1

EX14-5