Gibbs ProAXYZ 4AS 12-2005

ProAXYZ 4asby Productec

December 2, 2005

ProprietaryNoticeThis document contains propriety information of Gibbs and Associates and is to be used onlypursuant to and in conjunction with the license granted to the licensee with respect to theaccompanying Gibbs and Associates licensed software. Except as expressly permitted in the license, nopart of this document may be reproduced, transmitted, transcribed, stored in a retrieval system, ortranslated into any language or computer language, in any form or by any means, electronic,magnetic, optical, chemical, manual or otherwise, without the prior expressed written permissionfrom Gibbs and Associates or a duly authorized representative thereof.

It is strongly advised that users carefully review the license in order to understand the rights andobligations related to this licensed software and the accompanying documentation.

Use of the computer software and the user documentation has been provided pursuant to a Gibbs andAssociates licensing agreement.

©2005 Gibbs and Associates. All rights reserved. The Gibbs logo, GibbsCAM, GibbsCAM logo,CAM von Gibbs, Virtual Gibbs, Gibbs SFP, SolidSurfacer, MTM and “Powerfully Simple. SimplyPowerful.” are either trademark(s) or registered trademark(s) of Gibbs and Associates in theUnited States and/or other countries. Microsoft, Windows, and the Windows logo aretrademarks, or registered trademarks of Microsoft Corporation in the United States and/orother countries. All other brand or product names are trademarks or registered trademarks oftheir respective owners.

Written by Will Gaffga

Thanks to Bill Gibbs, Chris Romes, Bob Dunne and Bruce King for their input and assistance.

Printed in the United States of America

Gibbs and Associates323 Science Drive

Moorpark, CA 93021

Modified: December 2, 2005 2:04 pm

Table of Contents

Table of Contents

INTRODUCTION TO PROAXYZ 4AS 1

About ProAXYZ 4as . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3ProAXYZ 4as vs. Rotary Milling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Geometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9What is 4-Axis?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Toolpath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

PROAXYZ 4AS USE & INTERFACE 11

A Note About the Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Machining Icons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Contouring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Geometry for Contouring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Contouring Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Example 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Example 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Example 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Process Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

The Contour Process Dialog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17General Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Approach/Retract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Illustrated Example of the Clearance Planes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Lead In/Out. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Lead In/Out Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Approach Side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Roughing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Toolpath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Tool Shift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Segmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Understanding, Avoiding & Accepting Gouging with ProAXYZ 4as . . . . . . . . . . . . . . . . . . . . . . . 27

Pocketing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Approach/Retract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

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Spindle Feed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Toolpath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Segmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Custom Lead In/Out. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

PROAXYZ 4AS TUTORIALS 33

Basic Use. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Op 1 - Basic Contour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Op 2 - Inside Etching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Op 3 - Contour On Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Op 4 - Pocketing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Radial Tool On A Cam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Getting the Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Machining the Slot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Using Different Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46About the Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Operation 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Size of the Cam Shaft. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Making the Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Using Wall Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Cleaning the Toolpath . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Operation 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Setting up the Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Side Cut & Selecting Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53About the Pipe Cut Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

The Shape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Radial Lines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Operation 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Moving the Tool Relative to the Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56About the Ellipse part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56The operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Correcting the operations, part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Correcting the operations, part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Adding a Chamfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61About the Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Adding The Chamfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Operation 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Operation 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

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APPENDIX 65

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Helpful Formulas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Calculating Rotary Angles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

INDEX 71

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INTRODUCTION TO PROAXYZ 4AS

Introduction To ProAXYZ 4as

CHAPTER 2

: I n t r o d u c t i o n To P r oAXYZ 4a s

ABOUT PROAXYZ 4ASThe ProAXYZ 4as module by Productec provides simultaneous 4-axis machining of 3D geometryincluding support for Y-axis offsets. The Y-axis offset feature signifies the difference between ProAXYZ4as and the Rotary Milling module, which requires that the centerline of the tool passes through thecenter of the part. The ProAXYZ 4as module is compatible with the Mill, Rotary Milling, Mill/Turn,Advanced Milling and MTM™ modules.

If you will be working from solid models the Solids Import module is required for importing andextracting geometry to be cut. If you have either the 2.5D Solids or SolidSurfacer® module there isadditional ProAXYZ 4as functionality. These solids-based modules allow you to select faces andgeometry for controlling the tool axis.

Before continuing with this manual you should be familiar with, at a minimum, the Milling moduleand 2.5D Solids or SolidSurfacer modules if you will be using solids. This manual will not provide areview of how to use other GibbsCAM modules.

The ProAXYZ 4as module by Productec is activated with two DLLs (located in the plug-ins folder)and a hardware key or NLO license that has been configured for this feature. To support thesimultaneous 4-axis output your post processor must be upgraded. Please contact your reseller aboutupgrading post processors.

PROAXYZ 4AS VS. ROTARY MILLINGWhile both the ProAXYZ 4as and Rotary Milling modules program 4-axis milling the modules arevery different in their capabilities, the parts they can program, and the G-code they produce. Thechoice of which option to use is driven by the type of parts to be machined and how those parts aredefined.

!Please note that ProAXYZ 4as does not directly machine solids. Solids are used for extracting geometry and in some cases controlling the tool axis. ProAXYZ4as does not provide gouge protection on solids.

Function Rotary Milling ProAXYZ 4as

What it does Programs tool motion from “flat” geometry that is to be wrapped around a cylinder.

Programs tool motion from 3D geometry, as can be produced from solid models.

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Sources for Parts

Includes CAD features to create geometry either as flat or wrapped. It can import flat geometry through IGES, DXF, etc. It can convert 3D geometry into flat/wrapped or vice-versa, but is not well suited to this and is limited to a single 360 degree piece of geometry. As a result, Rotary Mill is a cumbersome tool for working on solid models or 3D geometry defined parts.

Can work from any imported solid, surfaces, or 3D wireframe geometry. It does not work with “flat” geometry. As such the modify, wrap and unwrap tools are available for wrapping geometry.

Depth and Tapers

Works well with constant depth milling, but not with tapered floors.

Works best with constant depth milling and also has a variety of tapered floor capabilities.

Wall Angles and Y Offsets

Works well with parts dimensioned with axial lengths and degrees of revolution. The tool is always a radial tool; there is no Y offset in the toolpath, restricting wall angle options.

Supports a variety of part wall angle orientations and Y offsets.

Y-Axis Compatibility

Works well with machines that do not have a Y-Axis, like some Mill-Turns and MTM machines.

Works well with Y-Axis machines and does not work well with machines that do not have a Y-Axis.

Types of Parts

Works very well with parts defined with flat geometry, like roller dies, or tool centerline grooves. It has Face and OD milling capabilities for Mill/Turns and MTMs.

The core technology is shared with ProAXYZ 5as, making it a 5-axis system at heart. While it gains a lot of capability from this, it is not optimized for the special cases where single-block multi-revolution output is created.

Post Compatibility

Requires a Rotary Mill option post processor, which can be combined with 3-axis Mill, Mill-Turns and MTM, but cannot be combined with an Advanced Mill post (5-axis positioning) or a TMS post.

Any GibbsCAM post can be upgraded for ProAXYZ 4as compatibility (or even 5as). ProAXYZ 4as can be combined into a TMS post processor, however you cannot program TMS operations and ProAXYZ 4as operations in the same part. You may do one or the other only.

Interpolation Options

Supports CNC Polar and Cylindrical Interpolation output options.

Does not support Polar and Cylindrical Interpolation output.


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TERMINOLOGYProAXYZ 4as introduces a number of new concepts to the GibbsCAM product line. While some ofthese concepts may be known to you, it is recommended that you read through the definitions toensure you understand how they are used with ProAXYZ 4as.

Prismatic Shape: A prismatic shape (surface or solid) is a 2D profile extruded along a depth axis, e.g., theshape can be 2D in XY, and extruded in Z. A 2-axis mill part is a combination of prismatic shapes.

Swept Surface or Swept Solid: A 3D shape that is created if a profile is moved around a closed shape. If theprofile is a line, the 3D shape is equivalent to a ruled surface. If the closed shape is 2D in XY, and theline is parallel to Z then a prismatic solid has been created.

Ruled Surface or Ruled Solid: A surface that is created by moving a line around a closed shape whilekeeping the other end of the line on a second shape. A ruled shape is a prismatic shape if the 2 HVshapes are identical, only offset in D. This causes the ruling line to always be parallel to D.

Radial: Radial refers to anything defined in relation to an axis of rotation.

Radial depth: The radial depth is the distance from the axis of rotation.

Radial line: A radial line is a line that passes through and is perpendicular to an axis of rotation.

Multi-revolution Output

Rotary Mill produces very optimal multi-revolution G-code output, creating unlimited revolutions on a single G-code line.

4as does not produce single line or single block multi-revolution output.


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Radial Shape or Radial Profile: A radial shape is a shape which lies on a cylinder around the axis of rotation.This is the radial equivalent to a 2D shape or profile.

Radial surface: A radial surface is a swept surface where the profile is a radial line. Typically the radialline sweeps around a radial shape. A radial surface is also any ruled surface where all the rule lines areradial lines.

Radially Prismatic: The radial equivalent to a prismatic shape.

Solids have walls and floors. A radially prismatic solid has walls that are radial surfaces and floors thatare cylinders, all from the same axis of rotation. Walls can be machined with the side of the tool, floorscan be machined with the bottom of the tool.

The big difference between 2-axis and 3-axis milling is that in 2-axis milling the walls are finished withthe side of the tool and the floors are finished with the bottom of the tool, while 3-axis milling cutseverything with the tangent point of tool contact. This same difference exists between radiallyprismatic rotary milling (the walls are finished with the side of the tool and floors with the bottom ofthe tool) and freeform rotary milling where everything is cut with the tangent contact point of thetool.

Freeform: Freeform refers to a solid of any shape. Rotary machining on a freeform shape is performedwith many passes, cutting with the tool's tangent point of contact.

Developable Surface: A developable surface is a surface that can be cut exactly with the side of a tool (acutting cylindrical shape). A developable surface is a ruled surface with constant normal vectors alongall ruled surfaces. Developable surfaces have parallel surface normal vectors along a surface line (notcurve) of tool cylinder contact. Prismatic surfaces are developable surfaces. Most radial surfaces, ruledsurfaces and swept surfaces are not developable surfaces. The safe way to cut non-developable surfacesis by using 3-axis or freeform rotary methods which is slow and expensive. If a surface is not

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developable there will be tool overcuts and undercuts that often can be “good enough” or withintolerance.

Many parts look like they can be cut on a rotary table with the side of a tool in a single pass. But canthey really be cut that way? Cut exactly that way? Frequently not. Usually the material can be cut closeenough or “within tolerance” to make a good part.

Further complicating the issue of cutting parts is the fact that CAD software and engineers frequentlydon't understand the geometric relationships of tool-to-part in rotary milling. Software and engineersoften are not very careful about how they model non-critical areas of the part. This can result in amodel that cannot be machined with radially prismatic 4-axis methods. As a result, most 4-axis rotarymilling is not about exactly machining a solid model. Most 4-axis machining is about understandingwhat the customer really wants in his part (which areas are critical, and which are not) and using goodmanufacturing judgment to apply 4-axis cutting methods to the part in a practical and efficient way.

The good news is that ProAXYZ 4as has been designed to give you the freedom to apply the cuttingmethods you choose to the model in the way you choose. ProAXYZ 4as does not force you to becontrolled by a poorly constructed solid model.

Transitional Element: A transitional element can be thought of as a patch between two surfaces, e.g. afillet. Transitional elements, when modeled, are rarely developable surfaces. Typically when a fillet isadded, the modeler does not specify a cone between two planes but rather a swept surface that is onlydefined along one side — usually the radius at the top.

Figure 1: A solid with a boss that is developable.

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Tool Interaction: A tool (a cylindricalshape) generally cannot cut a ruledsurface. The tool will attempt tofollow the curves of the surface,following the surface normals. Thesurface normals on a ruled surfacecan point in very differentdirections. The resulting point ofcontact is not a straight line.Different sections of the tool will be gouging or leaving excess material on the surface, resulting inan imperfect surface. The amount of the error is proportional to the size of the tool and how farthe normals are from each other.

Part-centric: The way GibbsCAM looks at parts. This means we think and talk about the part as if it isstationary and tools move around it. We do not think about machine motion. We think of cutting theway it is shown in CPR, so we say the tool is moving around the part, even though on a rotary tablemachine the part would be rotating.

4-axis Surface: A 4-axis surface is a surface that can be cut “good enough” with a 4-axis machine.

ProAXYZ 4as: The ProAXYZ module for machining 4-axis radially prismatic parts.

ProAXYZ 5as: The ProAXYZ module for machining 5-axis freeform parts.

Rotary Mill: The GibbsCAM option for wrapped geometry 4-axis milling.

MODELSGEOMETRYThe ProAXYZ 4as module by Productec uses selected geometry to control the cut shape anddirection. If you have a solid model simply extract the geometry you wish to machine. The geometryto be machined should be “radially prismatic” or radial around an axis. Radially prismatic shapes canbe finished with the bottom or side of a tool with lines and arcs. If a shape is not radially prismatic orneeds to be finished with a tangent point of the tool, it will have a lot of little moves and it likely needsto be cut on a 5-axis machine.

There are a number of problematic things to be aware of when cutting 4-axis parts, either from ablueprint, 2D geometry or solids. These include ruled surfaces, transitional features, fillet modelingand how the tool geometry interacts with the part. Because of ruled surfaces, transitional features,fillet modeling and tool interaction a model will often have a feature that cannot physically be cut asdesigned. In these cases a machinist needs to determine if “It is good enough”, which is to say withintolerance or the client’s needs.

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SOLIDSAs previously stated, ProAXYZ 4as supports solids and has additional functionality when creatingoperations using solids. Having said that, solids also present interesting difficulties, specifically in howthe solids were modeled. What may appear to be a 4-axis radially prismatic part on a blueprint mayhave been modeled such that it is not, particularly when dealing with “transitional elements”. Allinformation regarding ruled surfaces, developable surfaces, transitional elements and tool interactionstill apply when using solids.

What solids provide to ProAXYZ 4as is the ability to extract geometry and more importantly faceselection for controlling where the tool will go by controlling the tool axis. Of course if the surface isruled, the system will do its best to keep the output “good enough” based on your needs and input.

WHAT IS 4-AXIS?It is important to learn to differentiate between 4-axis capable parts and those that cannot be cut on a4-axis machine. Generally in a 4-axis part the lines that are perpendicular to the rotary axis (parallel tothe Y-Axis) must be overlapping when looking straight down on them. The following image is a valid4-axis part. The shape is fairly simple but it can be cut with ProAXYZ 4as. The walls of the bossoverlap each other. The angle of the boss may look strange since it is not radial but it can be cut with a4-axis machine. The walls along Y are radial and the tool angle can be changed to get into the corner.

TOOLPATHProAXYZ 4as produces two types of operations, Pocketing and Contouring. Pocketing clears an areawith radial walls. Contouring follows selected geometry, cutting with either the bottom of the tool orthe side of the tool. All clearance moves, entry/exit moves and cutting moves are defined andcontrolled by ProAXYZ 4as.

At this time ProAXYZ 4as is not capable of performing ID machining. This is an improvement for thefuture.

Figure 2: Example of a valid 4-axis part that may not appear to be machinable.

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10

PROAXYZ 4AS USE & INTERFACE

ProAXYZ 4as Use & Interface

CHAPTER 3

: P r oAXYZ 4a s U s e & I n t e r f a c e

A NOTE ABOUT THE INTERFACEProAXYZ 4as was developed as a GibbsCAM plug-in. Plug-ins are closely integrated into GibbsCAM,but often have minor differences in how they work. For example, the ProAXYZ 4as dialogs are modal,i.e. you can't change selections while they are up. Plug-ins don't use start point and end point markers.Plug-ins don't support transparency and other window and interface options.

MACHINING ICONSThe ProAXYZ 4as option adds two icons to themachining palette, one for 4-axis Contouring and onefor 4-axis Pocketing. Unlike other machining processes,it is recommended that you select the geometry (a pointand line or arc) to be machined before creating theprocess. This allows the process to properly setgeometry data (see “Curve” on page 23 for moreinformation). Beyond this, creating a ProAXYZ 4asprocess is identical to any other machining process, simply drag a Contouring or Pocketing icon to theProcess list and add a tool to the same tile. This opens a dialog where you set the parameters of theoperation.

CONTOURINGContouring has two basic objectives — control the path of the tool motion, and control the tool angle(the tilt) of the tool as it follows this path.

To give the user control over the path of the tool motion, contouring requires a geometry path asinput. Contouring calculates a sequence of tool movements based on a concept of a “controllingpoint”, which is a point that follows the geometric path from the start of the cut to the end of the cut.By default, contouring will position the tip of the tool on this controlling point throughout the cut. Anumber of user-specified parameters can cause the tool position to vary from this controlling point asthe tool travels along the path. The tool can be shifted up or down, left or right from the controllingpoint. Any variance in the tool position is calculated from the original path, and based on the travelingcontrolling point.

ContouringPocketing

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Similar to the “controlling point” concept, contouring also has away to control the tool angle, or tilt, of the tool as it cuts. A“controlling line” is calculated at every position of the tool as ittravels along the path. The controlling line is a “radial line”,meaning that it is a line that goes through the center of rotation ofthe machine’s rotary axis and also through the controlling point.Additionally, this line is always perpendicular to the machine’srotary axis. By default, the tool angle, or tilt, is set precisely parallelto this controlling line. A number of user-specified parameters cancause the tool tilt angle to vary from the controlling line, includingthe ability to use solid faces. The tool can lean forward orbackward, left or right, from the controlling line. Any variance inthe tool tilt angle is calculated from this traveling controlling line.

Additionally, it may be useful to consider a plane that goes through thecontrolling point, and is normal, or perpendicular to, the controllingline. This plane can be calculated at each position of the controllingpoint, as the controlling point travels along the geometrical path of thecut. Any left or right tool shift from the controlling point, is calculatedin this plane. And any up or down tool shift from the controlling point,is calculated normal to this plane.

Direction

Left

Lead

Lag

Right

Tool Axis

Figure 1: Tool Axis Control

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GEOMETRY FOR CONTOURINGThe geometry used for contouring operations should not have sharp corners. Internal corners(viewed in the cylinder tangent plane) should be larger than the Perp Cut/Dir value by more than alittle. External corners do not need a radius. The Tolerance value used should be smaller than theradius used. You may need to add fillets to a model before extracting your geometry, or select smallertools.

Contouring ExampleThis example uses a vertical mill 4-axis rotating A about X. Let’s consider a simple shape, a YZ planecircle centered on the rotary axis at Y0 Z0.

Example 1We have a 50mm diameter shaft and we need to cut a 6mm deep 13mm wide groove all the wayaround. There is a 38mm diameter circle geometry in the center floor of the groove. A 13mm tool willbe used to cut the groove. The geometry is selected and an operation is created with all optionsunchecked. The tool will cut the groove, and stay radial itself — centerline through rotary axis, 0 Yoffset.

Example 2The circle is not on the centerline of the groove floor, butrather on one floor edge. This time we specify a Tool Shift -Perp/Cut Dir (the same as a tool offset) of 6.5mm and cutalong the side of the geometry. The tool orientationmatches the radial angle through the prime point on thegeometry as it moves around.

Figure 2: Example of geometry in the center of a groove and the rendered operation.

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Example 3This time the circle is on the side of the groove at the OD.Example 2 is duplicated and a Depth - Constant value of -6.5from the geometry is specified.

Process SummaryYZ circles are quite simple but everything works off thesame principle. Create your geometry. Pick your startfeature and start point. Decide if you want the tool tofollow the geometry Z exactly, or use a Depth choice.Decide if you want the tool on center of the geometry inthe tangent cylinder plane, or shifted to the side with a ToolShift - Perp/Cut Dir value.

When cutting a wall, you will frequently have a tool radius value in the Perp/Cut Dir box. Plus valuesoffset to the left, minus values offset to the right. Even though the tool may move to one side, or upand down under Depth options, its radial alignment will be determined from a radial line through theprime point, at every position on the geometry. This will produce Y offsets in the toolpath and radialsurfaces on the part. This is a good choice for many parts.

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THE CONTOUR PROCESS DIALOGThe Contour dialog opens when a tool and process tile are combined. This dialog allows you to definehow a 4-axis contour will follow 3D geometry. Set the process parameters and click the OK buttonto set the process parameters and close the dialog. If you have not selected the geometry to machine,select a point and a line or curve (and perhaps faces of a solid) and then click Do It in the Machiningpalette. Click the Cancel button to close the dialog without making any changes.

General DataTolerance: This option allows you to set the accuracy of the toolpath alongthe selected geometry. This value is in part units.

Stock: Specify the thickness of material to be left on the part. The side ofthe material that stock is left on is defined by the Approach Side optionand will be measured from the Left or Right based on the Approach Sidesetting. This value is in part units.

Feedrate: Specify the cutting feedrate in millimeters per minute or inchesper minute.

Spindle RPM: Specify the rotation speed of the spindle in revolutions perminute.

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Lean Angle: This option is normally used with the abovealignment checkboxes unchecked. Using a Lean Angle value,you can cause the tool to be set to a particular angle in additionto the default radial angle. This is useful for cutting at aconstant angle such as an angled wall on a screw. The Toolpathoption “Progressive Lean Angle” can be used to move the toolback and forth to make a chamfer on a pocket.

Coolant Checkbox: If you wish to use coolant in this operationselect this option and select the type of coolant to use.

Approach/RetractThe Approach Retract values are basically thesame as any GibbsCAM process with theaddition of some data. All values entered hereare in part units.

Entry Clearance Plane: This value is not used byGibbsCAM.

Rapid Clearance: This value is an incrementaldistance measured up from the finish cutdepth. The resulting Z-axis rapid approachmove will always occur after the rotary axishas rotated to the correct starting angle. Therotary axis angle will be identical to the toolorientation at the first point of toolpath. The Z-axis approach move also occurs before any lead-inmoves. This item is similar to a Mill Contour or Pocketing Clearance Plane 2. This clearance valuecould be considered CP2a.

Feed Entry Clearance: This value is an incremental distance measured up from the finish cut depth. Thetool will rapid from the Rapid Clearance Z to the Z and will then feed to the cut depth. The rotaryaxis angle will be identical to the tool orientation at the first point of toolpath. The move occursbefore the Lead-in move. This item is similar to a Mill Contour or Pocketing Clearance Plane 2. Thisclearance value could be considered CP2b.

Feed Exit Clearance: This value is an incremental distance measured up from the finish cut depth. Therotary axis angle will be identical to the tool orientation at the last point of toolpath. This move occursafter the Lead-out move. This item is similar to a Mill Contour or Pocketing Clearance Plane 3. Thisclearance value could be considered CP3b.

Exit Clearance Plane: This value specifies the clearance plane for the operation. This value is an absoluteZ-value in the current CS (the machining CS). This item is similar to a Mill Contour or PocketingClearance Plane 3. This clearance value could be considered CP3a.

1 - Entry Clearance Plane2 - Rapid Clearance3 - Feed Entry Clearance

4 - Feed Exit Clearance5 - Exit Clearance Plane

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Illustrated Example of the Clearance PlanesThis example shows a part andhow the clearance values showup in a post. The top of this 4-axispart is at Z 2.5. The depth of cutset in the process dialog is 0.5, toa final depth of 2.0. The ClearancePlane set in the DocumentControl dialog (CP1) is 10. Theprocess clearances are as shownhere.

Below we can see the part (solid and geometry), the toolpath and the values of a few important points.The top of the part is at Z 2.5 (#1), the tool cuts 0.5 (#2) past that to 2.0. CP2a (#3) shows a depthvalue of 3, which is 1 above the finish cut depth. CP2b (#4) shows a value of 2.6, which is 0.6 above thefinish cut depth. The cut depth is 2.0 (#5). CP3b (#6) shows a value of 2.5, which is 0.5 above thefinish cut depth.

Let’s look at the posted code, important values have been highlighted.

Entry Values Exit Values

( TOOL 1 - .375 ROUGH ENDMILL )N5G0G90G54X-4.45Y-.25A37.8 (start angle)N6S5000M3N7G43Z10.H1 (CP1 from DCD)N8M8N9Z3. (CP2a)N10X-4.45Y-.25Z3.N11Z2.6 (CP2b)N12G1Z2.F50. (Cut Depth)

N1292X-4.2498Y-.25N1293G0Z2.5 (CP3b)N1294Z3.99 (CP3a)N1295Z10. (CP1 from DCD)N1296M9N1297G91G30Z0.N1298G90A0. (rotate back to straight)N1299G91G30Y0.N1300M30

CP2a

CP2b

CP2a

CP2b

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Lead In/OutLead In/Out ModeTangent Entry: This option sets atangent lead-in/out mode which isa linear move followed by a circularmove. When this option is selected,the Length, Radius and Angle fieldsare enabled and the Height field isdisabled

Ramp Entry: This option sets a Rampentry. When this option is enabledthe In Length, Height and Max RampAngle fields and the Out Heightfields are enabled.

Approach SideCenter: Select this option toapproach from on center. Whenused with Tangent Entry theapproach will move parallel to thefirst feature (in X, Y or XY) and will simultaneously move in Z. The rotary axis angle will already beidentical to the tool orientation at the first point of toolpath before the lead-in move begins. Also, therotary axis will not rotate during the lead-in move. I.e. this is a 2 - 3-axis simultaneous lead-in movethat does not use the rotary axis.

Alternatively, when used with Ramp Entry the approach will ramp parallel to the first feature (in X, Y orXY) and will simultaneously move in Z and also in the rotary axis. The rotary axis angle will beidentical to the tool orientation at the first point of toolpath where the lead-in ramp ends. I.e. this is a4-axis simultaneous lead-in move that uses the rotary axis.

Left: Select this option to approach from the left side of the shape. When used with the Tangent Entrythe approach will move parallel to the first feature (in X, Y or XY) and will not move in Z. The rotaryaxis angle will already be identical to the tool orientation at the first point of toolpath before the lead-in move begins. Also, the rotary axis will not rotate during the lead-in move. I.e. this is a 1 - 2-axissimultaneous lead-in move that does not use the rotary axis.

Alternatively, when used with Ramp Entry the approach will perform an XY-type zigzag whilesimultaneously rotating the rotary axis. The rotary axis angle will be identical to the tool orientationat the first point of toolpath where the lead-in zigzag ends. I.e. this is a 2 - 3-axis simultaneous lead-inmove that uses the rotary axis.

Right: Select this option to approach from the right side of the shape. This option behaves like Leftexcept that the lead-in moves are executed on the right side of the shape.

Center Left RightTangent Ramp

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RoughingSelect this option to define more thanone pass along the contour. The entrybehavior of the first pass is defined inthe main part of the dialog butsuccessive passes are defined in theRoughing dialog. Clicking theRoughing button opens a dialog whereyou can set the parameters.

Plunge: Select whether to plungeStraight into the material or to Rampinto the material. When Ramp is selected the Length and Angle fields are available to define the rampmotion.

Retract: This section allows you to define thetool motion between successive cuts.Selecting Full will cause the tool to rapid tothe operation’s Exit Clearance Plane. Thisoption is inactive when using Zig Zag.

The Height field is an extra option thatgenerates an incremental retract betweenroughing passes. If Full option is inactive thetool retracts by the Height value, move to thestart of the shape at the same height value andthen plunge to the first point of the new cut. With a closed shape this value is typically 0.

Using the Full option can be useful if you have an open shape. If the open contour starts on a cylinderat -90 and you cut all the way to +90, any retract along the tool axis will still see the tool going acrossthe part. If the Full option is used the tool will retract by the incremental value along the tool axis, thenwill move vertically (along the Z-Axis of the CS) to go to the absolute ZCP3 value, move across thepart staying at the ZCP3 value and then plunges back vertically (along the Z-Axis of the CS).

It is recommended that the Split Ops option is used if a process will use multiple shapes. This will causeeach disjoint shape to be its own operation. With machine-specific rotary head support built intosome GibbsCAM MDDs you will have more precise control over the retract moves betweenoperations. If you don’t use Split Ops, you don’t have any of these MDD-controlled clearance optionsavailable to help you control the moves, because the ops aren’t considered inter-operation moves.

Number of Cuts: Enter the total number of roughing passes to make.

Step: Enter the distance (step down) between each pass of the tool. This value is measured along thedirection of the tool axis. This is typically the depth of cut divided by the number of cuts.

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Zig Zag: Select this option to cause the tool to alternate its cutting direction between each pass.

Split Ops: This option can be used when there is more than 1 step taken to the final depth of theoperation. Selecting this option will break the single operation into an operation for each pass. This isparticularly useful when the start and end of each pass is not at the same angle. A retract from thiscondition might send the tool through the part. Since each pass is now a separate operation, a proper,safe retract can be generated.

ToolpathThe toolpath section controls tool behavior along geometry. You don't have to always have your toolaligned parallel to a radial line through the prime point on the geometry. You don't have to cut radialwalls. This section provides several options for other angles. There are 4 checkboxes to modify thetool angle (or “tool direction”) relative to the default radial alignment, and a Lean parameter foradjustment. Use a maximum of 1 option or you may use none if that suits your needs. If none of theoptions are selected then the system defaults to cut “radial walls”.

Except for the Radial Tool option, the prime point on the geometry is the pivot point for toolorientation changes. If you have lowered the tool tip below the geometry, don't be surprised to see itswinging back and forth with angle changes, creating retrograde (moving backward) tip motion. Thisis not invalid, but it can be undesired. Wall thicknesses will be most accurate at the geometry level.

4th Axis: This option is to define how the 4th axis is controlled duringthe operation. The tool orientation is defined by a radial direction atthe contact point on the selected shape. The rotary axis is defined bythe selected axis. Options include Around X, Y or Z (of CS1) andAround H, V or D of the current CS. Around X is typically used forvertical mills while Around Y is typically used for horizontal mills.

Radial Tool: This option forces the tool axis to be radial to the centerlineof rotation, eliminating Y offsets. The tool’s centerline will always go through the center line of thecurrent coordinate system. This is a good solution for machines without Y axes, as Y positions will notbe generated. This is similar to the GibbsCAM Rotary Mill option toolpath. The Radial Tool option isfrequently used for engraving. To support this, the tool will pivot around the center of a ball end mill,or otherwise the tool tip center for other tool shapes.

Tool Direction from Geometry: This option forces the tool orientation to be defined by the selected shape.This is intended for cutting cams with the bottom of the tool. Cams are non-circular. This choicekeeps the tool normal to the geometry in the rotary axis normal plane. The prime point on thegeometry is the pivot point which makes Depth shifts play a significant effect on tool motion. If thetool tip is on the geometry, with a Depth shift of 0.0, then the tip will follow the geometry, and all anglechanges occur above the tip (best results). If the geometry is above the tip and a Depth shift value is

!The system allows for more than one selection at a time. This is useful in ProAXYZ 5as but in ProAXYZ 4as only one option will work at a time.

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needed to lower the tip, you may get some tip swinging as the angles are pivoting at the geometrypoint level.

Side Cut: Select this option to cut the shape with the side of the tool rather than the bottom of the tool.This is useful when cutting the wall of a shape (not the floor or for solids). This option is typically usedin conjunction with face selections on a solid model. This option causes ProAXYZ 4as to get thenormal vector from the selected face at the prime point on the geometry and calculate the appropriate4-axis tilt at that point.

This works well with 4-axis surfaces, but can produce strange results from non-4-axis surfaces. In theexample of A-axis rotation about X starting on page 15, the circle examples produce a wall that issquare to the rotary axis, with no X variation — they are straight up and down. Picture this same wallwith a 5 degree draft angle or taper. This is no longer a 4-axis surface. The tool can't tilt in the Xdirection, only the Y direction. A 4-axis machine cannot cut this. Side Cut will produce strange results ifapplied to these surfaces. Side Cut pivots at the geometry level.

Progressive Lean Angle: This option will lean the tool overperpendicular to the geometry in the direction of the cut.The lean will change with the geometry. This option isnormally used with a Lean Angle value. It considersgeometry direction so that the tool will always lean to theleft, for example. It also adjusts the lean from full leanwhen moving parallel to the rotary axis, to 0 lean whenmoving perpendicular to the rotary axis. The value enteredis a maximum value.

CurveIf geometry was selected before the process wascreated the Full Shape field will display the length ofthe selected shape. The entire length of the selectedshape (open or closed) does not have to be machined.

Full Shape: Selecting the first Curve option will machinethe entire selected shape. This is the default selection.

Within the Shape: Selecting this option will allow you tomachine only a portion of the selected shape. The text boxes allow you to specify a distance (setbacks)from the start and end of the selected shape that will not be machined. The distance is measured alongthe shape.

Full Shape

Within the Shape

Shape Length

Full Shape

Start DistanceEnd Distance

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DepthIt is recommended that you examine a part’sgeometry in the rotary axis normal plane. Acommon mistake is to forget about geometry'sradial depth changes and wonder why the floor isbeing gouged.

Constant Depth: Specify the depth from the shape thatthe tool will cut. There is only a depth at start valuefor the constant depth. A positive or negativeincremental radial depth shift from the geometrymay be entered. The tool will still follow the radial depth of the geometry. A circle or cylinder aroundthe rotary axis has a constant radial depth.

Linear Variable Depth: This option generates toolpath that starts at one depth and ends at another. Thedepth along the cut shape will vary linearly (uniformly) from the Depth at Start to the Depth at End.This option still follows the geometry radial depth under the shifts.

Progressive Variable Depth: This option generates toolpath that starts at one depth and ends at another.The depth along the cut shape will vary progressively from the Depth at Start to the Depth at End beingtangent to a cylinder at the start and end. This option still follows the geometry radial depth under theshifts. This option is important for certain cam types. For this option to work properly theSegmentation values must not be “0”.

Constant Radius: This option will ignore the geometry's radial depth, and just cut the shape at a constantcylinder. The top of the tool will vary but the tip of the tool will remain at a constant radius value.This is useful when cutting tapered threads (you want to follow the top of the shape but doing so willgouge the part) or cutting flat geometry on a curved surface.

Profile: This option can control thedepth of the tool by with geometry in aworkgroup that gets revolved aroundthe rotation axis. This geometry worksas a guide that the tool will not violateif the cut geometry is below theprofile. To use this option draw a 2Dgeometry profile shape, it may be openand terminated or closed, that is in aworkgroup by itself. This geometry will control the Z depth of the tool while cutting anothergeometry shape in 4as. Be sure to select this workgroup in the workgroup selection menu next to theProfile option. Additionally, you can set an incremental value from the cut geometry in the Depth atStart box. Normally you'd cut with the tool at this depth using the R choice. Profile compares thisdepth (cut shape - Depth at Start) to the profile geometry and uses the profile geometry to calculatethe Z if it is higher.

Progressive Variable

ConstantLinear Variable

Constant Radius

Depth at Start

Depth at End

Profile

Workgroup

Profile Geometry

Toolpath

Helical Geometry

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Tool ShiftWhen cutting a wall, you will frequently have atool radius value in the Perp/Cut Dir box. Plusvalues offset to the left, minus values to theright. Even though the tool may move to oneside, or up and down under Depth options, itsradial alignment will be determined from aradial line through the prime point, at everyposition on the geometry. This will produce Yoffsets in the toolpath and radial surfaces on thepart. This is a good choice for many parts.

Along Cut Direction: This option modifies the position of the toolcontact point on the selected shape along the cut direction. Thisparameter is useful when cutting floors, not walls. Typically thisvalue is equal to the tool radius. In the following image we can seehow a tool is shifted along a shape so that the material is being cutwith the side of the tool rather than the bottom of the tool.

Along Cut Direction

Perpendicular to Cut Direction

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The example below shows the difference between a negative value (#1) and a positive value (#2)offset. If the toolpath were going in the opposite direction, the results would be the opposite, with anegative value outside the shape and a positive value inside the shape.

Perpendicular to Cut Direction: This option modifies theposition of the tool contact point on the selected shapeperpendicular to the tool axis and the cut direction. Thisparameter is useful when cutting walls. Typically thisvalue is equal to the tool radius. The example shows thedifference between a positive value (#1) and a negativevalue (#2) offset. In this situation the negative value isviolating the part. If the toolpath were going in theopposite direction, the results would be the opposite.

SegmentationMax Length: The Segmentation Max Length value is another term forthe toolpath’s chord height setting. Specify the maximum distancebetween 2 consecutive toolpath points along the contour. Thisvalue can be used to force the program to compute additionalpoints on near flat surfaces to get a smoother toolpath withouthaving to lower the machining tolerance. Setting this value to “0”turns the feature off. This can lead to a long, straight line between 2 points.

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Max Angle: Specify the maximum angle between the surface normals of 2 consecutive toolpath pointsalong the contour. This value can be used to force the program to compute additional points onsurfaces with high local curvatures to get a smoother toolpath without having to lower the machiningtolerance. Setting this value to “0” turns the feature off. Doing so allows the system to set the tool toany angle deemed appropriate. Entering an actual angle forces the tool to remain within that angle ofany selected geometry or faces.

UNDERSTANDING, AVOIDING & ACCEPTING GOUGING WITH PROAXYZ 4ASGouging is an undesirable thing to do, and the common result of incorrect use of ProAXYZ 4as.ProAXYZ 4as Contour cuts from geometry, and provides a lot of flexibility in controlling cuttingmotion and resulting part shapes. It doesn't know whether you are cutting a floor, a wall, or a wall anda floor. It is not cutting directly from a solid and has no knowledge of solid faces to avoid gouging. Itdoes not have a solid machining capability like SolidSurfacer and 2.5D Solids. It can certainly do a finejob machining geometry from solids, just not directly and automatically. Since it is driven bygeometry, the user is responsible for avoiding undesirable side effects of the tool geometry and toolmotion specified, just as in 2D or 3D programming from geometry.

A Conical Floor: The most common floor is a cylinder. Another is acone. A cone means that the floor's radial depth increases linearlyalong the axis of rotation. ProAXYZ 4as Contour does not have afloor face capability. The tool follows geometry. The cross section of acone is a circle in the rotary axis normal plane. If you program a toolto cut this circle, you will gouge the cone. ProAXYZ 4as places thetool tip on the geometry. Even a ball end mill will gouge, as the tip atgeometry depth is not the tool tangent point with the cone. A flattool will really gouge on the uphill side, and leave material on thedown hill side. On some parts this is ok and understood. On a recent large feedscrew part, thecustomer requested 3 passes with a 13mm flat end mill down the 35mm wide helix channel, with aconical floor. This left 3 big steps, each undercutting and overcutting. But it's what he wanted. Otherparts may require you to cut a precise conical floor. In this case you will want to adjust your toolpathto not gouge. For a constant angle cone, there is a single depth adjustment value that will raise thetool to not gouge. You can draw the geometry and calculate this adjustment, or you can set the finishsolid to act as the Stock Body, Zoom up on the part in CPR (or Flash CPR), and try different valuesuntil it looks good. You should be able to get within .005” or 0.1mm in just a few attempts.

Normal Plane Gouging: It is important to understand what a part’s geometry looks like in the rotary axisnormal plane, as an example, that being the YZ for the X-Axis. Parts with cylindrical floors look likecircles. Shapes that change radial depth will not look like circles.

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Lean/Tilt Gouging: Sincetools tilt away fromthe radial angle attheir geometry point,and if the tool tip is atthe geometry point indepth, it will lean/tiltabout its tip (RadialTool alignment isdifferent as notedabove). Even ifcutting a circle in thisview, tilting a ball endmill around its tip willgouge the circle. If you are not cutting a floor, this is not a problem. If you do have a floor, youneed to stop gouging. You can change your Depth option to Constant Radial Depth. This preventsgouging for a cylinder by adjusting the tool's depth automatically. But if your floor is not acylinder, you'll have to adjust the depth yourself, either by calculating the necessary adjustment,or eyeballing the necessary adjustment, as described in “A Conical Floor” above.

Geometry-Based Gouges: A flat tool following geometry will not gougea circle. But since it is keeping the center on the geometry, it willgouge any concave corner in this plane. So will a ball end mill. Theexception to this “always gouging” is when you are primarily cuttinga floor, and use the Tool Direction from Geometry option, which keepsthe tool normal to the geometry in this normal plane. Now a ballendmill will not gouge an inside fillet larger than the tool radius, butit will gouge a concave fillet smaller than the tool radius, or an insidesharp corner. None of this matters if you are not cutting a floor but itdoes matter if you are.

Tangent plane gouging: Visualizing your geometry as the tangent plane moves around the part allows youto think about it as if it were unwrapped and laid flat, like a 2D shape. If there is no Perpendicular to CutDirection value, there will be no geometric gouging, as the tool is on center. When you use aPerpendicular to Cut Direction value to offset the tool, your geometry must have radiuses, in the tangentplane, on the inside corners, larger than the Perp Cut/Dir value.

Depth gouging: Your tool follows the geometry depth in 3 of the 4 depth options. If you have a floor thatdoes not also follow the same depth changes, you will gouge the floor.

Flat Endmill Gouging Ball Endmill Gouging

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POCKETING4 Axes Pocketing supportsradial walls and cylindricalfloors, only. Pocketrequires a closed loop ofgeometry as its selection.This geometry should lieon a cylinder.Alternatively, you mayselect a cylindrical face asthe pocket floor. Pocketwill expand the tool out tothe centerline of the faceedge, or the centerline ofthe geometry. You can useStock to achieve a toolradius offset, if necessary.Pocket does not requirethat geometry haveradiuses on corners.Pocket produces radialwalls if you specify a tool radius value for Stock.

The Pocket dialog allows you to set the parameters for clearing out a 4-axis pocket. Click the Closebutton to close the dialog and save your process parameters. Select the shape you wish to cut and clickDo It in the Machining palette to create the operation.

APPROACH/RETRACTThe Approach/Retract values are basicallythe same as any GibbsCAM process with theaddition of some data. All values entered hereare in part units. For an illustrated example ofthese values and how they are output pleasesee page 19.

Entry Clearance Plane: This value is not used byGibbsCAM.

Rapid Clearance: This value is an incrementaldistance measured up from the finish cutdepth. The resulting Z-axis rapid approachmove will always occur after the rotary axis

1 - Entry Clearance Plane2 - Rapid Clearance3 - Feed Entry Clearance

4 - Feed Exit Clearance5 - Exit Clearance Plane

29


has rotated to the correct starting angle. The rotary axis angle will be identical to the tool orientationat the first point of toolpath. The Z-axis approach move also occurs before any lead-in moves. Thisitem is similar to a Mill Contour or Pocketing Clearance Plane 2. This clearance value could beconsidered CP2a.

Feed Entry Clearance: This value is an incremental distance measured up from the finish cut depth. Thetool will rapid from the Rapid Clearance Z to the Z and will then feed to the cut depth. The rotaryaxis angle will be identical to the tool orientation at the first point of toolpath. The move occursbefore the Lead-in move. This item is similar to a Mill Contour or Pocketing Clearance Plane 2. Thisclearance value could be considered CP2b.

Feed Exit Clearance: This value is an incremental distance measured up from the finish cut depth. Therotary axis angle will be identical to the tool orientation at the last point of toolpath. This move occursafter the Lead-out move. This item is similar to a Mill Contour or Pocketing Clearance Plane 3. Thisclearance value could be considered CP3b.

Exit Clearance Plane: This value specifies the clearance plane for the operation. This value is an absoluteZ-value in the current CS (the machining CS). This item is similar to a Mill Contour or PocketingClearance Plane 3. This clearance value could be considered CP3a.

SPINDLE FEEDSpindle RPM: Specify the rotation speed of the spindle in revolutions per minute.

Feedrate: Specify the cutting feedrate in millimeters per minute or inches per minute. For Inverse Timesimply enter the desired unit per minute feedrate and the post (if it supports inverse time) will convertthe value. For example, if the desired feedrate is 50 inches per minute then enter 50 in the dialog andthe post will convert “50” to the inverse time equivalent.

Plunge Feed: Specify the feedrate when plunging in millimeters per minute or inches per minute

Coolant Checkbox: If you wish to use coolant in this operation select this option and select the type ofcoolant to use.

CUTTINGStepOver: Specify the distance the tool will move over while pocketing. This should be less than orequal to the tool radius.

Stock: Specify the thickness of material to be left on the pocket. This value is in part units.

Tolerance: This option allows you to set the accuracy of the toolpath along the selected geometry. Thisvalue is in part units.

Depth: Specifies the depth above or below the selected geometry or solid face.

30


Reverse Tool Direction: This option generates identical toolpath but cuts in the opposite direction. It isdifficult for the system to predetermine whether the cut direction will be climb or conventional. If theresults are not what you want simply select this option and the toolpath will go in the oppositedirection.

Roughing: This option allows you to define thenumber of cuts (using N# Cuts) down the toolpathwill make to the final depth and the size of the Stepto take.

TOOLPATH4th Axis: This option is to define the 4th axis. The tool orientation isdefined by a radial direction at the contact point on the selected shape.The rotary axis is defined by the selected axis. Options include AroundX, Y or Z (of CS1) and Around H, V or D of the current CS.

Radial Tool: This option forces the tool axis to be radial.

SEGMENTATIONMax Length: Specify the maximum distance between 2 consecutivetoolpath points along the shape. This value can be used to force theprogram to compute additional points on near flat surfaces to get asmoother toolpath without having to lower the machiningtolerance. Setting this value to “0” turns the feature off.

Max Angle: Specify the maximum angle between the surface normals of 2 consecutive toolpath pointsalong the shape. This value can be used to force the program to compute additional points on surfaceswith high local curvatures to get a smoother toolpath without having to lower the machiningtolerance. Setting this value to “0” turns the feature off.

31


CUSTOM LEAD IN/OUTSelect the Custom Lead In/Out checkbox toenable an entry and/or exit move that is not astraight line. Click the Lead In/Out button todefine the moves. Click the OK button to saveyour changes or the Cancel button to close thedialog without saving your changes.

Spiral Lead In: Select this option to make thetool spiral down into the pocket. You candefine the size of the spiral (the Radius value)and how many times the tool will spiral (theTurns value) to the final depth. If a value of “0”is entered, the feature will not be output.

Last Cut Lead In/Out: Select this option to definea Line and/or 90˚ Radius move on the entry (Lead In) and exit (Lead Out) motion on the last pass of apocket. If a value of “0” is entered, the feature will not be output.

32

PROAXYZ 4AS TUTORIALS

ProAXYZ 4as Tutorials

CHAPTER 4 : P r oAXYZ 4a s Tu t o r i a l s

CreatingShapes

The ProAXYZ 4as tutorials provide an introduction to using the ProAXYZ 4as module. As with allGibbsCAM tutorials, the parts are in metric units and are set up with an Aluminum Alloy as theMaterial type. These tutorials assume you have existing knowledge of GibbsCAM Mill machining.As such, the parts have been simplified to focus only on what is important - ProAXYZ 4asinformation. The parts are already created and make extensive use of solids for the stock shape sothat we can focus on learning how to use ProAXYZ 4as, not focus on having to create geometryand make a lot of operations to make a “real” part. It is recommended that you have read or at leastperused the reference section of this manual so that you may complete and fully understand thesetutorials.

In some of these exercises we extract geometry from solids. If you do not have any solidscapabilities you may open the completed part files to work from geometry we have alreadyextracted.

BASIC USE

This purpose of this tutorial is tointroduce you to the ProAXYZ 4asinterface and its basic use. We willuse a single closed shape in orderto create three contour operationsand a pocketing op. Three separatecontour ops are being made toshow you how the various settingswill affect the toolpath.

� Open the part named Basic Use.vnc that is in the part files that came with the software.

Please note that the part geometry is not flat and it is not in a rotary mill workgroup. Thegeometry was created radially.

35

ProAXYZ 4as Tutorials – Basic Use

Op1

-BasicContour

OP 1 - BASIC CONTOURProAXYZ 4as Contouringrequires you to select apoint for the start locationand a feature that indicatesthe tool travel direction. Byselecting the geometrybefore creating the contourprocess, the system willcalculate the total shapelength, which can be veryuseful if you wish to entersetbacks for the toolpath,i.e. start and finish aspecified distance from thebeginning and end of theshape.

� Select point and line as shown.

We will start by etching outside the shape, offset by 5mm.

� Create contour process using Tool #1, the 13mm Spot Drill, using the parameters shown. Parameters that are particularly important in this situation are circled and explained below.

36


Op1

-BasicContour

1 - We have set the clearance plane to 85mm. The tool will rotate into position at 20mm abovethe part and rapid to 10mm above the part.

2 - We are ramping onto the part on the center of the shape.3 - We are rotating about X4 - The full shape is being cut.5 - We are cutting 1mm deeper than the shape.6 - We are offsetting the tool by 5mm to the right of the shape.

� Click OK to save the data and close the dialog.

� Click Do It to create the operation.

As it turns out, we don’twant to start in the cornerof the part so we need tomodify the geometry tohave a better startingpoint.

� Select the line we started the operation on and create a center point on it. Be sure to connect the geometry so that the new point is a part of the shape.

� Select the new point and the line to the right of it. Redo the operation.

Your results should look similar tothis image.

� Deselect this operation.

37


Op2

-InsideEtching

OP 2 - INSIDE ETCHINGWe will now create toolpath that is offset to the inside of the shape. We will use the same values asthe first operation except we will change a single value which will move the toolpath to theopposite side of the geometry by 10mm.

� Create a new contour operation using the same setup as the first operation but change the Perp Cut/Dir value to 10.

The results of this operation lookrather odd. In fact, the toolpath isviolating the shape to handle therotations we require. The largeoffset value is bigger than theshape can handle. Let’s changethis as the 10mm offset was usedas an example. Essentially wewere forcing the tool into a placeit could not fit.

38


Op2

-InsideEtching

� Change the Perp/Cut Dir value to 5 and redo the opertion.

If we render the part at this point it should look likethis image.

� Deselect operation #2.

39


Op3

-ContourOnCenter

OP 3 - CONTOUR ON CENTERWe will now machine a contour on the center of the geometry.

� Create a contour operation using Tool #2, the 5mm Finish Endmill, using the parameters shown. Parameters that are important to getting this operation right are circled.

We have specified that we are going tomachine on center (0 Perp/Cut Dir value) toa depth of 3mm below the geometry.

The results of the operation should looklike this image. This is the last of ourcontouring ops.

� Deselect this operation.

40


Op4

-Pocketing

OP 4 - POCKETINGWe will now pocket thissame geometry.

� Create a pocket operation using Tool #2 as shown.

We are leaving12mm of stock andcutting 8mm belowthe geometry.

� Click the Roughing button and set the values as shown. Then click OK.

� Click the Close button in the Pocket dialog to save the data and then click Do It to create the operation.

It seems we have made a mistake. The pocket isproduced but only in one step.

To get pocketing or contouring to actually make more than one pass youmust set the values and also select the Roughing checkbox.

� Open the Roughing process, select the Roughing checkbox and re-do the operation.

41


Op4

-Pocketing

The results should look like this. The roughing op leaves an obvious ledge, as would be expectedin a 4-axis operation. A contour operation would be needed clean this wall.

� Save this file as it is complete.

42

ProAXYZ 4as Tutorials – Radial Tool On A Cam

GettingtheGeom

etry

RADIAL TOOL ON A CAM

In this exercise we will force a tool to remain radial on a part.

GETTING THE GEOMETRY� Open the file “Barrel Cam.vnc” that is in the part files folder.

This is a barrel cam with a 6mm slot. We are going togenerate toolpath to cut this slot but the tool will remainradial as that is how the cam was designed.

� Extract edges to create the geometry shown.

Note that this does not include the rounded ends of the slot.You should select only three edges. We only want thegeometry that the tool will have to travel to create the shape.The end of the slot is a 3mm radius, the center of which goesthrough the center of the part. A 6mm tool can cut this slotand remain radial. This is illustrated in the following imagewhich has all of the geometry extracted from the shape.

43


MachiningtheSlot

MACHINING THE SLOT� Select the lowest point and arc on the slot geometry.

We do this so that the contour process knows the lengthof the geometry that will be cut. While we will not usethis data in this operation, always selecting yourgeometry first is a good habit to form when usingProAXYZ 4as. We also need to know how deep to cut.

� Select the Show Position item from the Plug-Ins menu.

� Switch the plug-in to determine thickness.

� Click anywhere near the slot on the curved surface of the barrel cam.

This will display the thicknessof the solid. We now know weneed to cut at least 8mm deep.

� Create a ProAXYZ 4as Contour process as shown using the 6mm Finish Endmill.

44


MachiningtheSlot

We have set the process to force the tool to remain radial (the Radial Tool option). If we did notselect this, the tool would simply follow the geometry and may generate moves in Y. We areoffsetting the depth by -9mm. This will ensure the tool clears the bottom of the slot. We havealso specified a Perp/Cut Dir value of 3mm. We are cutting a wall, so Perp/Cut Dir is a moreappropriate choice than Along Cut Dir. The 3mm value moves the 6mm tool off the geometry bya radius.

� Click OK to close the dialog and click Do It to create the Contour operation.

The results should look like the following image.

� Save the part as it is complete.

45

ProAXYZ 4as Tutorials – Using Different Geometry

AboutthePart

USING DIFFERENT GEOMETRY

This tutorial focuses on using the ConstantRadius option and how the walls of solids canhelp control the toolpath.

ABOUT THE PART� Open the file “Cam Shaft.vnc” that is in the part

files folder.

We have two parts in this file, both are thesame cam shaft but one has fillets(representing the final cut shape) and theother does not have fillets. The body withfillets is set as the stock shape. We havecreated two separate models todemonstrate different techniques you mayuse in ProAXYZ 4as.

The part also has two workgroupswith geometry extracted from themodels. The workgroup “TopProfile” contains geometryextracted from the outer edge ofthe “cam shaft” model. Theworkgroup “Bottom Profile”contains geometry extracted fromthe edges of the fillet on the“1.5mm fillet” model.

46


Operation1

OPERATION 1Size of the Cam Shaft

In the first operation we will machine the side ofthe cam that the geometry in workgroup 1 is on.The closed shape of the profile is fairly complex asits radial depth changes but we want to keep thetool tip at a constant depth, the depth of the shaft.We need to know what that depth is.

� Select the Show Position item from the Plug-Ins menu.

� Switch the plug-in to determine curvature.

� Activate face selection and click anywhere on the cam shaft near the origin.

This will display the radius ofthe solid. We now know weneed to cut to 12mm deep.

Making the Operation� Select the point and arc shown.

While we don’t have any lines to enterthe part on, this arc is fairly flat andstraight. It should work reasonablywell.

47


Operation1

� Create a ProAXYZ 4as Contour operation using Tool #1 as shown.

We have specified a Side Cut because we are concerned with cutting the walls of the cam. ThePerp/Cut Dir value is equal to the tool radius. The Depth is set to 12mm using the ConstantRadius setting. That means that the tool will follow the path of the geometry but the tool willnot adjust its depth.

� Click OK to save the data and close the Contour4 dialog.

� Create the contour operation and render the part.

Unfortunately this violates the part. We can see this clearly by looking at the left side of the part.The tool is doing what we asked; it is remaining normal to the geometry and is cutting the wall

48


Operation1

and is remaining radial. This is not good enough. To make it good enough, we can use the solidmodel to help control the 4th axis rotations.

Using Wall SelectionProAXYZ 4as does not work from solids, which would give us all the normal benefits thatmachining solids provides, such as gouge protection. Having said that, ProAXYZ 4as cantemporarily use a solid to control the tool’s angle. Basically the system makes virtual geometryfrom a selected face and aligns the tool to the virtual geometry. We are going to use thisfunction to avoid the gouge.

� Turn on face selection.

� Select any face of the cam that is enclosed by the geometry, i.e. the any of the faces we are attempting to cut.

� Right click on the face and choose Select Wall Faces from the menu.

This will select all of the faces that will bemachined. Please note that there are morethan the six arrows seen to the right.

� With the faces and geometry selected, redo the operation.

Cleaning the ToolpathIf we look at the concave corner near thetop of the part we can see that there is a

49


Operation1

small section where the tool goes backwards then forwards. This is due to the change in thetool’s angle based on the selected faces. We can make this a little cleaner by changing a fewvalues.

� Open the contour process and change the values as shown.

By providing a Max Angle value we will restrain the tool from going more than 1˚ past parallelwith a face and the tighter Tolerance will make cleaner toolpath.

� Redo the operation.

Now the part should be correct. The toolpathstill has a location where the tool cuts back, andthis is not entirely avoidable. This toolpathrepresents the tool tip, not the contact point soany location where the tool rapidly changes itsorientation can lead to a situation similar tothis. We have minimized the effect of this andwere we to use the Analyze Cut Part option inFlash CPR we would see that we are neither gouging nor leaving any material behind. If wereally did not want to have the tool cut back we could extract the geometry from the bottom ofthe shape and have the tool follow that curve rather than the top shape.

50


Operation2

OPERATION 2Setting up the Operation

The next operation will use thegeometry from the fillets on thesecond cam. The depth of the floorhere is 15mm. If you wish to confirmthis for yourself, use the Show Positionplug-in as we did earlier in the tutorial.

� Using the same selection technique as before, select the walls that need to be machined, but use the model with fillets.

� In addition to the faces, select the point and arc on the outer geometry as shown.

� Using Tool #1, create a contouring operation as shown.

The information is the same as before except we have changed the constant depth to 15mm.

� Click OK to close the dialog and then create the operation.

51


Operation2

This creates good toolpath that followsthe selected shape, does not gouge thewalls and remains at a constant depth.The nice thing is that it doesn’t matterwhich set of geometry we choose.

� If you deselected the operation, double click it.

� While holding down the Ctrl key, deselect the point and arc then select the matching point and arc on the geometry that represents the bottom of the fillet.


The toolpath is identical. The tooltip isgoing to be in the same location foreither set of geometry because we areusing selected walls and the Perp/CutDir value have not changed. If thegeometry was different, that is to say,not matching the fillet, then the toolpath would be different, but that would also be an entirelydifferent part.

� Save the part.

52

ProAXYZ 4as Tutorials – Side Cut & Selecting Faces

AboutthePipeCutPart

SIDE CUT & SELECTING FACES

ABOUT THE PIPE CUT PARTThis part has an existing Rotary Mill operation. We will see that this part cannot be properly cutusing the Rotary Mill option even though it looks like it can. We will create a ProAXYZ 4asoperation that properly cuts the part. As stated, this part can’t be cut with Rotary Mill — thegeometry goes through center and the tool must go through center for Rotary Mill.

� Open the file “Pipe Cut.vnc”.

� Select the body and run Flash CPR.

� When the operation is finished activate Analyze Cut Part and select the Undercuts on cut part option.

We can clearly see that the tool is cutting too deepat the bottom of the shape. Let’s look at why thisis happening.

The Shape� Switch to CS2 (the XY plane) and Workgroup 1.

� Turn on face selection and right click anywhere in the cutout section of the model. Then choose Select Tangent Faces.

Now that the loop of faces that define thecutout are selected we will extractgeometry and see what is going on.

� Open the geometry palette, click the Geometry From Solids button and finally the Geometry Extraction option.

� Extract the geometry with a tolerance of 0.

We will now create some lines throughpoints.

� Create lines through the two sets of points shown.

53


Operation1

Radial Lines� Switch to the Home view.

We can see that the lines run through X0Y0, i.e. the linesare radial. With Rotary Milling, the tool must be radial.That is why we are removing too much material.

Fortunately, ProAXYZ 4as handles Y offsets. We need torecreate this operation using ProAXYZ 4as.

OPERATION 1� Delete the existing operation 1.

We will use the geometry we just created as our contour shape with a mid-point added for thestart location.

� Create a mid-point on the line on the Y+ side of the outer profile geometry.

You will need to disconnect, create a duplicate line and reconnect geometry to complete this.

� Create a ProAXYZ 4as Contour process with Tool #1 as shown.

Be sure to set the 4th Axis to Around Z as this is on a Mill/Turn machine.

54


Operation1

� Create and render the operation.

If we run the cut part analysis we can see that thecorners are being cut too deep. We need to selectthe walls of the solid to control the tool’salignment.

� Using the same selection method as before, add the walls to

the selected geometry (hold down the key and select

the walls).


The rendered operation is good. You might bewondering about the little “hitches” near the corner of the toolpath. These are normal and to beexpected as tools swing around the transition from one wall to another. We have told the tool tomaintain its tip at -7mm and that is what it is doing during the transition.

� Save the part as it is complete.

55

ProAXYZ 4as Tutorials – Moving the Tool Relative to the Geometry

AbouttheEllipsepart

MOVING THE TOOL RELATIVE TO THE GEOMETRY

ABOUT THE ELLIPSE PARTIn this exercise we are going to experiment with theTool Direction From Geometry option and look atanother way to use Tool Shift.

� Open the file Ellipse.vnc.

We are only concerned with the ellipticalgeometry shapes around the profile of the part.While other sections of this part can be cut withProAXYZ 4as, we are focusing on these profiles tolearn more about controlling ProAXYZ 4astoolpath.

THE OPERATIONS� Select the point and line shown then create a ProAXYZ 4as Contour operation using Tool #1 and the process

parameters seen below.

� Repeat this process for the other open ellipse. Rather than starting at the top of the part, select the point and curve at the bottom of the part so that the tool will retract, reposition and then feed back onto the part.

56


Theoperations

The resulting toolpath should look like this image.

Correcting the operations, part 1Unfortunately when this isrendered, we see there is avery bad result. The toolstarts off tangent to thepoint selected and is radial.As the tool progressesaround the part it remainsradial and removes a lot ofmaterial it shouldn’t.

57


Theoperations

� Open Operation 1, set the Toolpath option to Tool Dir From Geometry then redo the operation and repeat this process for Operation 2.

Now when rendered wecan see that the tool doesnot gouge the part. Thetool orientation is definedby the geometry. The toolis kept normal to thegeometry and since theDepth setting is 0 the tooltip follows the geometryexactly and all anglechanges occur above thetip.

58


Theoperations

Correcting the operations, part 2We aren’t quite done with this part yet. You may have noticed that the part is being cut with thebottom of the tool. This is most noticeable as the tool goes around the apex of the open ellipses.Cutting with the bottom of the tool is not optimal so we are going to pull the tool back a little sothat it cuts with its leading edge.

� Open Operation 1, set the Along Cut Dir option to -25mm then redo the operation. Repeat this process for operation 2.

We can see that the toolpath is no longer exactly on the geometry. This is because the toolpathrepresents the tooltip. Looking at this image we can see that the center of the tool is exactly on

59


Theoperations

the toolpath. By offsetting the tool by a radius the leading edge of the tool is now cutting thematerial first. The leading edge of the tool is effectively following the geometry.

Modifying the Tool Shift along the direction of cut is also a very useful technique for cuttingthreads, see page 25 for more information and another example.

� Save this part as it is complete.

60

ProAXYZ 4as Tutorials – Adding a Chamfer

AboutthePart

ADDING A CHAMFER

ABOUT THE PARTIn this tutorial we are going to add two types of chamfersto an existing part. The first chamfer will simply use a spotdrill to create a 1mm chamfer around the top of the boss.The second chamfer will create a 30˚ chamfer on two sidesof the boss using the Progressive Lean Angle option.

� Open the file Progressive Lean.vnc.

This is a rather simple part with an existing ProAXYZ4as Contour operation that trims a little material off ofthe boss.

ADDING THE CHAMFERSOperation 2� Select the same geometry that is used in Operation 1.

Be sure to deselect operation 1 as it is required.

� Create a ProAXYZ 4as contour operation using Tool #2 as shown.

61


AddingTheCham

fers

This is a very basic operation where we are running the tool on the outside of the geometry,cutting 1mm deep. When rendered you should see the edge of the boss has been given achamfer. This is simple stuff that could be done with Rotary Mill.

Operation 3We will now make a chamfer that Rotary Mill cannot do. Let’s imagine that this part wasdesigned with a different chamfer. Rather than a standard 45˚ edge the sides of the boss have a30˚ edge. We need to be able to lay the tool over by 30˚. Using the Lean Angle we can lay the toolover but that fixes the tool to the angle specified. Fortunately the Toolpath section has aProgressive Lean Angle option. This option will progressively move the tool to the lean angle as itapproaches parallel to the rotary axis. As the tool moves towards perpendicular to the rotaryaxis the tool is moved back to 0˚.

� Select the point and line shown on the lower closed shape.

These are the same points as in theother operations, but using the lowerclosed shape. We are using a differentshape to set the bottom of the chamfer.

� Create a ProAXYZ 4as contour operation using Tool #1 as shown.

62


AddingTheCham

fers

The Depth could actually be set to adifferent value and we would get avirtually identical result. We used thisvalue so we can clearly see what ishappening. The Perp/Cut Dir value isthe same as is used in Operation 1.When rendered the part should looklike this image. Note how the toolchanges its angle. This is a very usefultechnique.

� Save the file as it is complete.

63


AddingTheCham

fers

64

APPENDIX

Appendix

CHAPTER 5 : App e n d i x

GLOSSARYProAXYZ 4as introduces a number of new concepts to the GibbsCAM product line. While some ofthese concepts may be known to you, it is recommended that you read through the definitions toensure you understand how they are used with ProAXYZ 4as. Italicized items may be found within theglossary.

4-axis Surface A 4-axis surface is a surface that can be cut “good enough” with a 4-axis machine.

4as The ProAXYZ module for machining 4-axis radially prismatic parts.

5as The ProAXYZ module for machining 5-axis freeform parts.

Developable Surface

A developable surface is a surface that can be cut exactly with the side of a tool (acutting cylindrical shape). Developable surfaces have parallel surface normalvectors along a surface line (not curve) of tool cylinder contact. Prismaticsurfaces are developable surfaces. Most radial surfaces, ruled surfaces and sweptsurfaces are not developable surfaces. The safe way to cut non-developablesurfaces is by using 3-axis or freeform rotary methods which are slow andexpensive.

Freeform Freeform refers to a solid of any shape. Rotary machining on a freeform shape isperformed with many passes, cutting with the tool's tangent point of contact.

Part-centric The way GibbsCAM looks at parts. This means we think and talk about the partas if it is stationary and tools move around it. We do not think about machinemotion. We think of cutting the way it is shown in CPR, so we say the tool ismoving around the part, even though on a rotary table machine the part wouldbe rotating.

Prismatic Shape A prismatic shape (surface or solid) is a 2D profile extruded along a depth axis,e.g., the shape can be 2D in XY, and extruded in Z. A 2-axis mill part is acombination of prismatic shapes.

Radial Radial refers to anything defined in relation to an axis of rotation.

Radial depth The radial depth is the distance from the axis of rotation.

Radial line A radial line is a line that passes through and is perpendicular to an axis ofrotation.

Radial Shape or Radial Profile

A radial shape is a shape which lies on a cylinder around the axis of rotation. Thisis the radial equivalent to a 2D shape or profile.

67

Appendix

HELPFUL FORMULASCALCULATING ROTARY ANGLESThe two formulas below are for determining an unknown angle or an unknown distance whenworking with wrapped and unwrapped geometry.

• If you have a known angle and need to determine what length it will be when unwrapped use thefollowing formula.

For example, we have a 2.5”cylinder and the angle is 60˚ wecan calculate the length of theline to be 2.618”.

Radial surface A radial surface is a swept surface where the profile is a radial line. Typically theradial line sweeps around a radial shape).

A radial surface is also any ruled surface where all the rule lines are radial lines.

Radially Prismatic The radial equivalent to a prismatic shape.

Rotary Mill The GibbsCAM option for wrapped geometry 4-axis milling.

Ruled Surface or Ruled Solid

A surface that is created by moving a line around a closed shape while keepingthe other end of the line on a second shape. A ruled shape is a prismatic shape ifthe 2 HV shapes are identical, only offset in D. This causes the ruling line toalways be parallel to D.

Swept Surface or Swept Solid

A 3D shape that is created if a profile is moved around a closed shape. If theprofile is a line, the 3D shape is equivalent to a ruled surface. If the closed shape is2D in XY, and the line is parallel to Z then a prismatic solid has been created.

LengthRadius Angle π××

180----------------------------------------------------=

2.5 60 3.1416××180

----------------------------------------------- 2.618=

68

Appendix

• If you have a known length and need to determine what angle it will be when wrapped use thefollowing formula.

For example, we have a line thatis 2.618” long that is going to bewrapped around a 2.5” cylinderwe can calculate the angle to be60˚.

AngleLength 180×( ) π÷

Radius---------------------------------------------------=

2.618 180×( ) 3.1416÷2.5

-------------------------------------------------------------- 60=

69

Appendix

70

Index

NUMERICS4 axis Surface: 8

defined: 674th Axis Selection: 22, 31

AAlong Cut Direction, Tool Shift: 25Approach: 20

CCenter Approach: 20Constant Depth: 24Constant Radius: 24Coolant Checkbox: 18, 30Custom Lead In/Out, Pocketing: 32

DDepth: 30Depth options: 24Developable Surface: 6

defined: 67

EEntry Clearance Plane: 18, 29Exit Clearance Plane: 18, 30

FFeed Entry Clearance: 18, 30Feed Exit Clearance: 18, 30Feedrate: 17, 30Freeform: 6

defined: 67

Full retract: 21Full Shape, Curve option: 23

HHeight retract: 21

IID machining: 9

LLast Cut Lead In/Out: 32Lead In/Out button: 32Lean Angle: 18, 62Left side approach: 20Linear Variable Depth: 24

MMax Angle, Segmentation: 27, 31Max Length, Segmentation: 26, 31

NNumber of Cuts, Roughing option: 21

PPart-centric: 8

defined: 67Perp/Cut Dir: 16Perpendicular to Cut Direction, Tool Shift: 26Plunge Feed: 30Plunge, Roughing entry option: 21Prismatic Shape: 5

defined: 67

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Index

ProAXYZ 4as: 8defined: 67

ProAXYZ 5as: 8defined: 67

Profile, depth control: 24Progressive Lean Angle: 23, 62Progressive Variable Depth: 24

RRadial: 5

defined: 67Radial depth: 5

defined: 67Radial line: 5Radial Shape

defined: 67Radial Shape or Radial Profile: 6Radial surface: 6

defined: 68Radial Tool: 22, 31Radially Prismatic: 6, 8

defined: 68Ramp Entry: 20Ramp, plunge entry: 21Rapid Clearance: 18, 29Retract full: 21Retract height: 21Retract, Roughing option: 21Reverse Tool Direction: 31Right side approach: 20Rotary Mill: 8

defined: 68Roughing: 31Roughing, Lead In/Out option: 21Ruled Surface

defined: 68Ruled Surface or Ruled Solid: 5

SSide Cut: 23Spindle RPM: 17, 30Spiral Lead In: 32Split Ops: 21Split Ops, Roughing option: 22Step, Roughing option: 21StepOver: 30Stock: 17, 30Straight, plunge entry: 21Swept Surface

defined: 68Swept Surface or Swept Solid: 5

TTangent Entry/Exit: 20Tolerance: 17, 30Tool Direction from Geometry: 22Tool Shift: 25Transitional Element: 7, 9

WWithin the Shape, Curve option: 23

ZZig Zag, Roughing option: 22

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Gibbs ProAXYZ 4AS 12-2005

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