Chapter 2 Sketching, Constraining & Dimensioning

Chapter 2Sketching, Constraining & Dimensioning

Chapter 2 - Objectives • After completing this chapter, you will be able to do the following: • Change the sketch and part options • Sketch an outline of a part • Create geometric constraints • Use construction geometry to help constrain sketches • Dimension a sketch • Create dimensions using the automatic dimensioning tool • Change a dimension’s value in a sketch • Import AutoCAD DWG data

Sketch & Part - Application Options • Options • Customized your preferences • Settings are global • Affects all open & new Inventor documents

Sketch - Application Options • Constraint Placement Priority • Display • Overconstrained Dimensions • Snap to Grid • Edit dimensions when created • Autoproject edges during curve creation • Autoproject edges for sketch creation and edit • Autoproject part origin on sketch create • 3D Sketch

Part - Application Options • Sketch on New Part Creation • Construction • Auto-hide in-line work features • Auto-hide in-line work features • Auto-consume Work Features and Surface features

Part - Application Options • 3D Grip Dimensional Constraint Relocation • 3D Grip Geometric Constraint Relocation

Units • Units • Default unit of measurement • Part, Assembly & Drawing files • Template file • Changing - Overridden • Edit dimension

Templates • Templates • New files created from a template • Add or Modify templates • Template directory • Subdirectory • New Tab

Creating a Part • From the Open dialog box click the Standard.ipt icon in the Open dialog box • From the New file drop list on the Standard toolbar

Creating a Part • Sketches & Default Planes • Sketch plane • 2D objects are sketched • Active sketch • Three planes • XY,YZ, and XZ • Three Axes • X, Y, and Z • Center • Origin - point at the intersection • Browser • New Sketch • Active sketch

Sketch the Outline of the Part • Step 1 - Sketches Overview • Sketching strategies, tools, & techniques • Outline • Draw to finished size/shape • Visual Guide – distance & angle • No overlaps & gaps • Keep shape simple • Closed vs. Open shape • Sketch Tools • Sketching tools • Expert mode on/off

Sketch the Outline of the Part • Using the Sketch Tools • Visual feedback • Line Tool • Powerful tool • Endpoint - Arc • Inferred Points • Dashed lines • Endpoints • horizontal • vertical • perpendicular

Sketch the Outline of the Part • Automatic Constraints • Constraint symbols • Scrubbing • different constraint applied • move the cursor so it touches • Selecting Objects • individually objects • multiple objects • color change • Deleting Objects • right-click

Measure Tools • Measure • Distances • Points • Edges • Faces • Parts • Angles • Loops • Area • Region Properties

Analysis Tools • Measure • Additional Options • Click the arrow in the Measure dialog box

Exercise 2-1 • Creating A Sketch with Lines Exercise 2-2 • Creating a Sketch with Tangencies

Constraining the Sketch • Step 2 - Geometric Constraints • Apply behavior • Create relationships • Status Bar • Fully constrain • Fix constrain • Constraint Types • 11 geometric constraints

Constraining the Sketch • Geometric Constraints • Adding Constraints • Applying • Over-constrain • Constraint Visibility

Constraining the Sketch • Geometric Constraints • Dragging a Sketch • Constrained or Not • Geometry stretches • Showing Constraints • Show all & Hide all F8 and F9 • To see applied constraints • Objects change color • Deleting Constraints • Right-click or Delete key

Construction Geometry • Standard toolbar • Add dimensions and constraints • Not visible when a feature is created • Always available in the sketch

Exercise 2-3 • Adding and Displaying Constraints

Adding Dimensions • Step 3 – Adding Dimensions • All dimensions created are parametric • Control & change size of geometry • General Dimensioning • Create linear, angle, radial, or diameter • Automatically snap • Extension lines • Preview image • Dimensioning Lines • Endpoints - two • Length • Dimensioning an Angle • Two lines

Adding Dimensions • Dimensioning Arcs and Circles • Circumference • Arc = radius • Circle = diameter • Diametric Dimensions • Revolved part • Represent a quarter outline • Linear diameter • Axis of rotation • Dimensioning to a Tangency • Arc or circle • Constraint symbol changes • Two quadrants

Adding Dimensions • Entering and Editing a Dimension’s Value • Automatically appear • Change the value • Edit Dimension option • Default value • To change double-click • Enter exact value • Accurate to six decimal places • Smallest dimensions first

Adding Dimensions • Entering and Editing a Dimension’s Value • Repositioning a Dimension • New location • Origin points cannot be moved • Over-Constrained Sketches • Inventor will not allow • over-constrain • duplicate constraints • conflict with another constraint • Driven dimension • Reference dimension • Parentheses • Over-constrained dimensions option

Adding Dimensions • Auto Dimension • Automatically apply • Dimensions • Constraints • State number of dimensions or constraints required to fully constrain the sketch • First apply critical constraints and dimensions • Will not override or replace existing constraints or dimensions

Exercise 2-4 • Dimensioning A Sketch

Opening/Importing AutoCAD Files • Copy to clipboard within AutoCAD and Paste in Inventor • Open/Import AutoCAD & AutoCAD Mechanical Files • New Drawing • New Part • Title Block • Border • Symbol • 2D and 3D • Import 2D geometry to an active sketch (part or drawing)

Move and Scale Tools • Move • Move the objects to another location • Scale • Scale sketch

Importing Other File Types • SAT • STEP • PRO/E up to Version 20 • DXF • IGES • Construction Environment • Toolset

Exercise 2-5 • Inserting an AutoCAD File

Applying Your Skills • Skill Exercise 2-1 • Skill Exercise 2-2

Chapter 2 Sketching, Constraining & Dimensioning