Chapter 2 Sketching, Constraining & Dimensioning

1. Chapter 2Sketching, Constraining & Dimensioning

2. Chapter 2 - Objectives • After completing this chapter, you will be able to • Change the sketch and part options as needed • Sketch an outline of a part • Create geometric constraints • Dimension a sketch • Create dimensions using the automatic dimensioning tool • Change a dimension’s value in a sketch • Import AutoCAD DWG data

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

4. 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 • 3D Sketch

5. Part - Application Options • Sketch on New Part Creation • Parallel view on sketch creation • Auto-hide in-line work features • Construction

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

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

8. Creating a Part • New icon • Part environment • Creating a Part • Standard.ipt icon • File menu • Shortcut key

9. 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

10. 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 it simple • Closed vs. Open shape • Sketch Tools • Sketching tools • Expert mode on/off

11. 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

12. Sketch the Outline of the Part • Automatic Constraints • Constraint symbols • Scrubbing • different constraint applied • move the cursor so it touches • Precise Input • specified length or angle • Selecting Objects • individually objects • multiple objects • color change • Deleting Objects • right-click

13. Measure Tools • Analyze • Sketch • Part • Assembly models • Measure • Distances • Angles • Loops • Area

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

15. Exercise 2-1 • Creating A Sketch With Lines Exercise 2-2 • Creating a Sketch With Tangencies

16. Constraining the Sketch • Step 2 - Geometric Constraints • Apply behavior • Create relationships • fully constrain • fix constrain • Constraint Types • 11 geometric constraints

17. Constraining the Sketch • Geometric Constraints • Adding Constraints • Applying • Over-constrain • Duplicate “Adding this constraint will over-constrain the sketch” • Snap • Midpoint, center & intersection • Coincident constraint

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

19. Exercise 2-3 • Adding and Displaying Constraints

20. 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

21. 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

22. 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

23. 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

24. 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

25. Exercise 2-4 • Dimensioning A Sketch

26. Opening/Importing AutoCAD Files • Opening/Importing AutoCAD Files 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)

27. Summary

28. Summary

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