1. Two-Dimensional Sketching
Using Autodesk® Inventor™

2. Chapter Objectives Introduce the 2D sketch commands
Sketch an outline of a part
Create geometric constraints
Use construction geometry to help constrain sketches
Dimension a sketch
Show how to edit 2D shapes
Change a dimension’s value in a sketch
NOTE: When you get to a slide with blue background, complete the task identified using the Autodesk Inventor software.

3. Part Browser and Origins Folder

4. Creating a Part New Sketch Sketches & Default Planes Active sketch
Origin Folder in Browser Bar
Three planes
XY, YZ, and XZ
Three Axes
X, Y, and Z
Center Point
Origin – coordinates are 0,0,0
TECHNICAL NOTES
Settings specified on the application options and document settings dialog boxes determine orientation of the sketch objects and default sketch plane.

5. STEP #1: Sketch the basic shape of the object, keep it simple.
TIPS FOR SKETCHING
STEP #1: Sketch the basic shape of the object, keep it simple.
Geometry should not overlap.
Geometry should form a closed region.
STEP #2: Add constraints.
STEP #3: Add dimensions.
STEP #4: Select “Finish Sketch” from the ribbon.

6. Use the 2D Sketch Tab on the Ribbon
Draw Panel
Pattern Panel
Modify Panel
Format Panel
Exit Panel

7. Sketching Tools & Command
Spline
Ellipse
Rectangle
Chamfer
Polygon
Mirror
Rectangular Pattern
Circular Pattern
Offset
Trim
Extend
Move
Rotate
Scale
Text

8. Geometric Constraints

9. Geometric Constraint Symbols
Geometric constraints control the relationship between the geometric entities that make up a sketch.
When you sketch using tools such as the Line command, geometric constraint symbols appear on the screen as applicable.
A geometric constraint symbol is a visual clue that shows alignments, perpendicularities, tangencies, and other commonly used relationships.

10. Constraints
The Constraints tool contains 12 tools that can be used to change and define the shape of a sketch.
Status Bar (bottom right of the graphics window) shows the number of dimensions & restraints remaining to be applied.

11. Constraints The Constraints are: Perpendicular Parallel Horizontal
Vertical
Equal
Tangent – indicates a curve or line touching without overlapping another geometric element.
Symmetric – indicates lines or curves to by bisect around a selected line.
Concentric – indicates centers of circles share the same centerpoint.
Colinear – causes two or more line segments to align with one another.
Coincident – indicates endpoints are aligned with other geometric elements.
Smooth – applies a curved conditions to a spline.
Fix – locks geometry in place relative to the UCS.
TEACHER NOTE
Encourage students to view the Learn About Constraints video on the Getting Started screen. Click File>Getting Started>Learn About Constraints.

12. Show Constraints
The Show Constraints command will show the constraints applied to a sketch.
Show all F8
Hide all F9
Selecting - objects change color
Deleting – right click or delete key
Base sketches should always be fully constrained.
Click and drag the sketch

13. Line & Fillet Sketch Tools

14. Line Line Tool Inferred Points Straight Lines Endpoint – Arc
Dashed lines
Endpoints
horizontal
vertical
perpendicular

15. Fillet
A fillet is a rounded edge or corner that is added to an existing entity

16. Chamfer
A chamfer is a beveled edge or corner added to an existing entity.
Chamfers may be defined in one of three ways
With two equal distances
With two distances that are not equal
With a distance and an angle

17. Chamfer

18. Chamfer

19. Chamfer

20. Parametric Modeling: Overview
Start a new part file and create a rough sketch of the basic shape show below on the XY plane. This will be the base feature.

21. Dimensions

22. Adding Dimensions All dimensions created are parametric
Dimensions control & change the size of geometry
General Dimensioning
Create linear, angle, radial, or diameter
Automatically snap
Extension lines
Dimensioning Lines
Touch endpoints – two clicks
Touch line length – one click
TECHNICAL NOTE
Sketch tab of the Application Options dialog box: select Edit dimension when created option to immediately open the edit dimension box. To edit dimensions later, clear the check box.

23. Adding Dimensions Over-Constrained Sketches Driven dimension
Inventor will not allow
over-constrain
duplicate constraints
conflict with another constraint
Driven dimension
Reference dimension
Parentheses
Can be added manually
Sketch tab, format panel

24. Adding Dimensions
Auto Dimension
DO NOT USE!!!

25. Parametric Modeling: Overview
Apply and modify constraints and dimensions to the 2D sketch shown below. You should have two equal constraints and two dimensions ONLY!

26. Extrusion Feature Tool

27. Parametric Modeling: Overview
Extrude the parametric 2D sketch to create the base solid feature of the design below.

28. Parametric Modeling: Overview
Add parametric features to complete the design.
Use the top plane to create a new sketch, add dimensions and constraints, ensure the sketch is fully constrained, and extrude it the same distance as the overall height of the object. Use the “TO” EXTENTS option and select the bottom of the object..

29. Circle & Arc Sketch Tools

30. Circle There are two ways to sketch a circle using Inventor
Select a center point then define a diameter
Define three tangent points

31. Arc There are three ways to draw arcs using Inventor
Select three points
Define a tangent
Select a center point

32. Parametric Modeling: Overview
Add holes to complete the design. Ensure all sketches are fully constrained. Save as EX2-EMB.

33. Spline The Spline tool command is a flyout from the Line command
An open spline is a curved line
A closed spline is an enclosed curved line on which the start and end points are the same point

34. Ellipse The Ellipse tool is a flyout from the Center point circle tool
A centerline defines the first axis of the ellipse
The cursor is then moved above the centerline to define the elliptical shape

35. Rectangle There are four ways to sketch a rectangle using Inventor
By selecting two points
By selecting three points
By selecting a center and two points
By selecting a center and three points

36. Start a new part file and create a rough sketch of the basic shape show below on the XZ plane. Ensure the viewcube is rotated to the correct orientation (“TOP” reads left to right). Finish the sketch and Extrude the object .25”.

37. Rectangular Pattern, Circular Pattern, & Mirror Sketch Tools

38. Rectangular Pattern

39. Rectangular Pattern
The Rectangular Pattern command is used to create rectangular arrays of rows and columns

40. Rectangular Pattern

41. Create a new sketch on the top view and create a circle concentric to one of the fillets using the dimension below.

42. Using the Rectangular Pattern (on the Sketch Tab), pattern the circle using the specifications below and click OK.

43. Use the Extrude Cut feature, ALL Extents to complete the holes.

44. Circular Pattern
The Circular Pattern tool is used to array an object around a common center point

45. Circular Pattern

46. Circular Pattern

47. Circular Pattern

48. Circular Pattern

49. Mirror
The Mirror command creates a reverse copy (mirror image) of an existing sketch
Mirror is helpful when creating symmetrical images

50. Extend, Trim, & Offset Sketch Tools

51. Extend and Trim
The Extend command is used to lengthen an existing line
The Trim command is used to shorten an existing line

52. Offset
The Offset command is used to create lines parallel to existing lines at a specified distance
Circles and curves may also be offset

53. Complete the part by creating a new sketch on the top plane
Complete the part by creating a new sketch on the top plane. Draw three circles, dimension only one circle using 2.5 diameter, and use the EQUAL constraint for the other two. Use a HORIZONTAL constraint to align the circle center points. Use the TRIM command to create the feature below. Ensure your sketch is fully constrained and finish the sketch.

54. Extrude/Cut the sketch using the ALL extents. Save the file as EX2-PPT.

55. Polygon Sketch Tool

56. Polygon
The Polygon command can be used to sketch either an inscribed or a circumscribed polygon
Polygons can be measured in one of two ways
Distance across flats (circumscribed)
Distance across corners (inscribed)

57. Inscribed Polygon

58. Circumscribed Polygon

59. Move, Copy, Rotate, & Scale Sketch Tools

60. Move The Move command is used to reposition an existing sketch
It can also be used to copy an existing sketch

61. Rotate
The Rotate command is used to rotate a sketch about a point

63. Scale
Change the size of an entity or sketch.

64. Text
The Text command is located on the Draw Panel and is used to add text to a sketch

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

66. Construction Geometry Sketch Tools

67. Construction Geometry
Sketch Tab – Format Panel
Not visible when a feature is created
TECHNICAL NOTES
Constraints are automatically inferred as you sketch. Add only the minimum number of constraints needed to control the sketch shape.
Use Show All Constraints to identify which constraints have been inferred. If you want geometry to have a different constraint, delete the unwanted constraint and reapply a different constraint.

68. Selection Options Selecting Objects Deleting Objects
Crossing vs Selection
Color change
Selection – left to right, red
Crossing – right to left, gree
Deleting Objects
Right-click
TECHNICAL NOTES
Scrubbing: Brush the cursor along the line or curve you want to constrain to, then move the cursor into the approximate desired position. In cases where more than one constraint is possible, this technique overrides a default constraint in favor of the constraint you selected.
Precise input: enter exact coordinates for sketch geometry as you sketch.
Selecting geometry:
Click and drag left to right to select all geometry completely enclosed in the selection window.
Click and drag right to left to select geometry enclosed and intersected by the selection window.

69. Sketch Doctor & Open Loops