1. CAM与自动编程
封志明

2. VIII、 Fixed-Axis Surface Contouring
--Chapter VIII--
Fixed-Axis Milling Overview
How to Create Planar Milling Operation
Fixed-Axis Milling Geometry
Fixed-Axis Milling Drive Method
Mechanical University

3. To be able to Create Fixed-axis contour Milling.
Chapter VIII
To understand the Fixed-axis milling.
To understand the Drive Methods of Fixed-axis Surface Contouring.
Objectives
To be able to Create Fixed-axis contour Milling.

4. 8.1 Surface Contouring Overview
8.1.1 Surface Contouring Introduction
Fixed-axis Surface Contouring operations and Variable-axis Surface Contouring operations finish areas on contoured surfaces by removing material along the part contours. You can control the Tool Axis and Projection Vector options to create tool paths that follow the contours of very complex surfaces.
Surface Contouring
For Fixed-axis Surface Contouring operations , the tool axis remains parallel to a specified vector.
For Variable-axis Surface Contouring operations, the tool axis constantly changes orientation as it moves along the tool path.

5. 8.1 Surface Contouring Overview
8.1.1 Surface Contouring Introduction
To create a Surface Contouring operation, you should specify:
Part Geometry (optional) 1
Drive Geometry 2
Projection Vector (required if Part Geometry is specified) 3
Tool Axis 4

6. 8.1 Surface Contouring Overview
8.1.1 Surface Contouring Introduction
Drive Geometry can include part geometry or geometry that is not associated with the part. The software creates drive points from the specified Drive Geometry to control the tool position.
When Part Geometry is not specified, the software positions the tool directly on the drive points.
When Part Geometry is specified, the software positions the tool where the drive points project onto the Part Geometry.
The selected Drive Method determines how you define the drive points required to create a tool path.

7. 8.1 Surface Contouring Overview
8.1.1 Surface Contouring Introduction
The selected Drive Method determines how you define the drive points required to create a tool path. Some Drive Methods create a string of drive points along a curve while others create an array of drive points within an area.
The Projection Vector defines how the drive points project to the Part Surface, and which side of the Part Surface the tool contacts.
The selected Drive Method determines which Projection Vectors are available.

8. 1. Fixed-Axis Milling Overview 8.1 Surface Contouring Overview
8.1.1 Surface Contouring Introduction
Mill
Fixed Axis
Variable Axis
Planar Mill
Contour Mill
Surface Contour
Sequential Mill
Cavity Mill

9. 1. Fixed-Axis Milling Overview 8.1 Surface Contouring Overview
8.1.2 Fixed-axis Surface Contouring Operation Subtypes

10. 1. Fixed-Axis Milling Overview 8.1 Surface Contouring Overview
Suitable Occasion
Drive Geometry
Tool axis remains parallel to a specified vector.
Define the drive Points required to create a tool path
Complex surfaces finishing

11. 1. Fixed-Axis Milling Overview
8.2 Valid geometry for Fixed-axis Surface Contouring
Geometry
Tab.8-2 Valid geometry for Fixed-axis Surface Contouring

12. 1. Fixed-Axis Milling Overview
8.2 Valid geometry for Fixed-axis Surface Contouring
Geometry
The specified part geometry works in combination with the drive geometry (usually a boundary) to define the cut region.
You may specify Bodies (sheet or solid), Faceted Bodies, Surface Region features, or Faces as Part Geometry.

13. 1. Fixed-Axis Milling Overview
8.3 Drive Methods
Drive Method
Drive methods define the Drive Points required to create a tool path. It allow you to create a string of Drive Points along a curve or an array of Drive Points within a boundary.

14. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
10 Methods
Method
Definition 1
Curve/Point
Defines Drive geometry by specifying points and selecting curves 2
Spiral
Defines Drive Points that spiral outward from a specified center point 3
Boundary
Defines cut regions by specifying Boundaries and Loops 4
Area Milling
Defines cut regions by specifying Cut Area geometry. Drive geometry isn't required. 5
Surface Area
Defines an array of Drive Points that lie on a grid of Drive Surfaces

15. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
10 Methods
Method
Definition 6
Streamline
Builds an implied drive surface from the selected geometry 7
Tool Path
Defines Drive Points along the tool path of an existing CLSF to create a similar Surface Contouring tool path 8
Radial Cut
Generate Drive Paths perpendicular to and along a given boundary, using a specified Stepover distance, Bandwidth and Cut Type 9
Flow Cut
Generates Drive Points along concave corners and valleys formed by Part Surfaces 10
Text
Select annotation and specify a depth to engrave text on the part.

16. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
① Curve/Point
When specifying points, the Drive Path is created as linear segments between the specified points.
When specifying curves or edges, Drive Points are generated along the selected curves and edges.
The curves may be open or closed, contiguous or noncontiguous, planar or non-planar.
Points for Open Path
Points for Closed Path
Drive geometry defined by curves

17. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
① Curve/Point
Custom Cut Feed Rate
add custom feed rate values to each set of curves.
Cut Step
Number : Controls the number of points placed on each curve or edge
Tolerance : Specify the maximum allowable chordal deviation between the Drive Curve and the line extending between two consecutive Drive Points.

18. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
② Spiral
The drive points are created within the plane normal to the projection vector and containing the center point.
It maintains a constant cutting speed and smooth motion, so it is useful for high speed machining applications.
The Center Point defines the center of the spiral and it is where the tool begins cutting.
Spiral Drive Method

19. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
② Spiral
Max Spiral Radius
Limits the area to be machined by specifying a Maximum Radius

20. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
② Spiral
Stepover
Specifies the distances between successive cut passes
Stepover Distance for Spiral Drive

21. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
② Spiral
Cut Direction
Defines the direction the Drive Path cuts in relationship to the spindle rotation
Climb Cut and Conventional Cut

22. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
③ Boundary
Cut regions are defined by Boundaries, Loops, or a combination of both.
It works in much the same way as Planar Milling.
Boundaries may be created from a sequence of curves, an existing permanent boundary, points, or a face.
Boundary Drive Method

23. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
③ Boundary
Tolerance
Specify the inside and outside tolerance values for the boundary
Offsets
Specify how much material to leave along the boundary
Containment
Defines cut regions by creating loops along exterior edges of selected part

24. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
④ Area Milling
It’s similar to the Boundary Drive Method, but requires no drive geometry.
Cut Area may be defined by selecting Surface Regions, Sheet Bodies, or Faces.
You may further constrain the cut regions by Steep Containment.
You should use the Area Milling Drive Method in place of the Boundary Drive Method whenever possible.
Boundary Drive Method

25. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
④ Area Milling
Steep Containment
restricts the cut area based on the steepness of the tool path
Non-steep
Directional Steep

26. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
④ Area Milling
Stepover
specifies the distances between successive cut passes
The 1 indicates the scallop height, and the 2 indicates the stepover

27. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑦ Radial Cut
The Radial Cut Drive Method enables you to generate Drive Paths perpendicular to and along a given boundary, using a specified Stepover distance, Bandwidth and Cut Type.
This drive method is useful in creating cleanup operations.
Radial Cut Drive Method
Direction is Defined by Boundary Indicators

28. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑦ Radial Cut
Band on Material/ Opposite Side
Defines the total width of the machined area measured in the plane of the boundary.
Path Direction
Determines the direction the tool travels along the boundary.

29. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑨ Flow Cut
It is used for Removing excess material in corners prior to finishing or Removing the uncut material left behind by a previous, larger ball cutter.
It generates tool paths one level at a time along the concave corners and valleys formed by part surfaces.
It avoids embedding the tool when it moves from one side to the other.
Flow cut

30. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑨ Flow Cut
Maximum Concavity
determine which sharp corners and deep valleys will be cut
Concavity Angle

31. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑨ Flow Cut
Concavity of 179 Degrees
Concavity of 160 Degrees

32. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑨ Flow Cut
Flowcut type
Single Pass
Multiple Passes
Reference Tool Offsets
Reference Tool

33. 4. Fixed-Axis Milling Drive Method
8.3 Drive Methods
⑨ Flow Cut
Reference Tool Diameter specifies the width of the finishing cut region based on the diameter of the roughing ball cutter. The software calculates the bi-tangency contact points from the specified Reference Tool Diameter and then uses these points to define the cut region for the finishing operation.
Reference Tool

34. 4. Fixed-Axis Milling Drive Method
8.4 Drive Methods
Projection Vector enables you to define how the Drive Points project to the Part Surface, and the side of the Part Surface the tool contacts.
The types of Projection Vectors available depend upon the Drive Method. The Projection Vector option is common to all Drive Methods except Flow Cut.
Drive Point Projects to Part Surface

35. 4. Fixed-Axis Milling Drive Method
8.6 Create a Fixed Contouring operation
Steps
① On the Insert toolbar, click Create Operation    , or choose Insert→Operation.
② In the Operation Subtype group, click FIXED_CONTOUR
③ In the Location group, select the following:
Program
PROGRAM
Tool
MILL
Geometry
WORKPIECE
Method
MILL_FINISH
④ Click OK, the Fixed-Contour Mill dialog box is displayed.
⑤ Select Drive Method.
⑥ Click Generate  .

36. 4. Fixed-Axis Milling Drive Method
8.7 Fixed Contouring operation Example
Flowcut Multiple operation Path
Fixed Contouring Operation Model
Area Milling Drive Method

37. THANKS
封志明/机械工程学院
2019年4月27日