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Getting Started with VisualMill Version 4.0

The Solid/Surface/STL Model Manufacturing System

VisualMill

MecSof

0

t Corporation

End-User Software License Agreement

This MecSoft Corporation's VisualMill End User Software License Agreement that accompanies the VisualMill(TM) software product (“Software”) and related documentation ("Documentation"). The term "Software" shall also include any upgrades, modified versions or updates of the Software licensed to you by MecSoft.

MecSoft Corporation grants to you a nonexclusive license to use the Software and Documentation, provided that you agree to the following:

1. USE OF THE SOFTWARE.

You may install and use one copy of the Software on a single computer in a single location on a hard disk.

2. COPYRIGHT.

The Software is owned by MecSoft Corporation and its suppliers. The Software’s structure, organization and code are the valuable trade secrets of MecSoft Corporation and its suppliers. The Software is also protected by United States Copyright Law and International Treaty provisions. You must treat the Software just as you would any other copyrighted material, such as a book. You may not copy the Software or the Documentation, except as set forth in the "Use of the Software" section. Any copies that you are permitted to make pursuant to this Agreement must contain the same copyright and other proprietary notices that appear on or in the Software. You agree not to modify, adapt, translate, reverse engineer, de-compile, disassemble or otherwise attempt to discover the source code of the Software. Trademarks shall be used in accordance with accepted trademark practice, including identification of trademark owner’s name.

Trademarks can only be used to identify printed output produced by the Software. Such use of any trademark does not give you any rights of ownership in that trademark. Except as stated above, this Agreement does not grant you any intellectual property rights in the Software.

3. TRANSFER.

You may not rent, lease, sublicense or lend the Software or Documentation.

4. LIMITED WARRANTY.

MecSoft Corporation warrants to you that the Software will perform substantially in accordance with the Documentation for the thirty (30) day period following your receipt of the Software. To make a warranty claim, you must notify MecSoft Corporation within such thirty (30) day period. If the Software does not perform substantially in accordance with the Documentation, the entire and exclusive liability and remedy shall be limited to either the replacement of the Software or the refund of the license fee you paid for the Software.

MECSOFT CORPORATION AND ITS SUPPLIERS DO NOT AND CANNOT WARRANT THE PERFORMANCE OR RESULTS YOU MAY OBTAIN BY USING THE SOFTWARE. THE FOREGOING STATES THE SOLE AND EXCLUSIVE REMEDIES FOR MECSOFT CORPORATION’S OR ITS SUPPLIERS’ BREACH OF WARRANTY. EXCEPT FOR THE FOREGOING LIMITED WARRANTY, MECSOFT CORPORATION AND ITS SUPPLIERS MAKE NO WARRANTIES, EXPRESS OR IMPLIED, AS TO THE NON-INFRINGEMENT OF THIRD PARTY RIGHTS, MECHANTABILITY, OR FITNESS FOR ANY PARTICULAR PURPOSE. IN NO EVENT WILL MECSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE TO YOU FOR ANY CONSEQUENTIAL, INCIDENTAL OR SPECIAL DAMAGES, INCLUDING ANY LOST PROFITS OR LOST SAVINGS, EVEN IF A MECSOFT CORPORATION REPRESENTATIVE

Getting Started with VisualMill

HAS BEEN ADVISED OF THE POSSIBLITY OF SUCH DAMAGES OR FOR ANY CLAIM BY ANY THIRD PARTY.

Some states or jurisdictions do not allow the exclusion or limitation of incidental, consequential or special damages, or the exclusion of implied warranties or limitations on how long an implied warranty may last, so the above limitations may not apply to you. To the extent permissible, any implied warranties are limited to thirty (30) days. This warranty gives you specific legal rights. You may have other rights which vary from state to state or jurisdiction to jurisdiction. For further warranty information, please contact MecSoft Corporation’s Customer Support.

5. GOVERNING LAW AND GOVERNING PROVISIONS.

This Agreement will be governed by the laws in force in the State of California excluding the application of its conflicts of law rules. This Agreement will not be governed by the United Nations Convention on Contracts for the International Sale of Goods, the application of which is expressly excluded. If any part of this Agreement is found void and unenforceable, it will not affect the validity of the balance of the Agreement, which shall remain valid and enforceable according to its terms. You agree that the Software will not be shipped, transferred or exported into any country or used in any manner prohibited by the United States Export Administration Act or any other export laws, restrictions or regulations. This Agreement shall automatically terminate upon failure by you to comply with its terms. This Agreement may only be modified in writing signed by an authorized officer of MecSoft Corporation.

6. U.S. GOVERNMENT RESTRICTED RIGHTS

Use, duplication, or disclosure by the government is subject to restrictions as set forth in subparagraph (c) (1) (ii) of The Rights in Technical Data and Computer Software clause at DFARS 252.227-7013 or subparagraphs (c) (1) and (2) of Commercial Computer Software – Restricted Rights at 48 CFR 52.227-19, as applicable. Manufacturer is: MecSoft Corporation, 17905, Sky Park Circle, Suite N, Irvine CA – 92614-6386, USA.

Unpublished - rights reserved under the copyright laws of the United States.

MecSoft Corporation 17905, Sky Park Circle, Suite N Irvine, CA 92614-6386

VisualMill is a registered trademark of MecSoft Corporation © 1998-2003, MecSoft Corporation

Trademark credits

Windows is a registered trademark of Microsoft Corporation Pentium is a registered trademark of Intel Corporation Parasolid is a registered trademark of Unigraphics Solutions SolidWorks is a registered trademark of SolidWorks Corporation Solid Edge is a registered trademark of Unigraphics Solutions Rhino is a registered trademark of McNeel & Associates.

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Table of Contents Welcome to VisualMill ............................................................................................................................. 6

About This Guide................................................................................................................................... 6

VisualMill Configurations ..................................................................................................................... 6

Computer Requirements ........................................................................................................................ 7

Installing VisualMill .............................................................................................................................. 7

Installing the VisualMill Security Key.............................................................................................. 7

Security Key Problems...................................................................................................................... 8

VisualMill Installation Folder ........................................................................................................... 8

Running VisualMill................................................................................................................................ 9

Registering VisualMill ...................................................................................................................... 9

VisualMill Display .......................................................................................................................... 10

VisualMill User Interface ....................................................................................................................... 12 Typical Scenario .................................................................................................................................. 14

Programming the Workflow ................................................................................................................ 14

Machining Operations ............................................................................................................................ 15 3 Axis Operations................................................................................................................................. 16

2½ Axis Operations.............................................................................................................................. 26

Drilling Operations .............................................................................................................................. 31

Fourth Axis Operations ........................................................................................................................ 33

Tutorial 1: 3 Axis Milling ....................................................................................................................... 35 The File Toolbar................................................................................................................................... 35

Loading a Part Model........................................................................................................................... 35

View Toolbar ....................................................................................................................................... 37

Creating the Stock................................................................................................................................ 38

Browser ................................................................................................................................................ 40

Geom Tab........................................................................................................................................ 41

Mops Tab......................................................................................................................................... 42

Tools Tab......................................................................................................................................... 42

Creating Tools...................................................................................................................................... 43

Setting Feeds and Speeds ..................................................................................................................... 47

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Customizing Feeds and Speeds ....................................................................................................... 48

Status Bar ............................................................................................................................................. 51

Creating the Horizontal Roughing Toolpath........................................................................................ 51

VCR Toolbar........................................................................................................................................ 55

Simulating the Horizontal Roughing Toolpath.................................................................................... 56

Creating the Pre-Finish Toolpath ......................................................................................................... 58

Creating the Pencil Tracing Toolpath .................................................................................................. 60

Creating the Finish Toolpath................................................................................................................ 62

Post-Processing .................................................................................................................................... 65

Set Post Options .............................................................................................................................. 66

Post Processor Generator ................................................................................................................ 67

Post-Processor Problems ................................................................................................................. 69

Tutorial 2: 2½ Axis Milling Operations................................................................................................ 70 Creating Tools and Stock..................................................................................................................... 70

Creating Regions.................................................................................................................................. 73

Selecting Regions................................................................................................................................. 78

Multiple Regions ............................................................................................................................. 79

Creating Toolpaths ............................................................................................................................... 79

Clearance Plane.................................................................................................................................... 84

Adjusting the Regions.......................................................................................................................... 92

Replacing the First Toolpath................................................................................................................ 94

Modifying Toolpath Parameters .......................................................................................................... 96

Toolpath Editing .................................................................................................................................. 99

Tutorial 3: Drilling Operations ........................................................................................................... 109

Tutorial 4: 4th Axis Machining Operations ........................................................................................ 115 Creating Fourth Axis Toolpaths......................................................................................................... 115

Cutting Strategy ................................................................................................................................. 115

Measurement Toolbar ........................................................................................................................ 116

Setting the Machine Zero ................................................................................................................... 117

Setting the Rotation Axis ................................................................................................................... 119

Creating the Parting Plane.................................................................................................................. 120

Creating 3 Axis Roughing Toolpaths................................................................................................. 125

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Creating 4th Axis Indexed Mode Finishing Operations ..................................................................... 131

Creating 4th Axis Continuous Mode Finishing Operation ................................................................. 135

Additional Topics .................................................................................................................................. 138 Creating Surfaces ............................................................................................................................... 138

Knowledge Base ................................................................................................................................ 139

Where to go for more help ................................................................................................................... 139

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Welcome to VisualMill

Welcome to VisualMill and thank you for choosing one of most powerful and easy to use Solids/Surface/STL manufacturing packages on the market today.

VisualMill is a unique, Windows-based, CAM product that seamlessly integrates toolpath generation and cutting simulation/verification, in one package that is both easy and fun to use. VisualMill’s machining technology capabilities enable you to produce toolpaths that you can send to the machine with utmost confidence. A simple and well-planned user interface makes VisualMill suitable for use on the shop floor, working in conjunction with your existing CAD/CAM/CNC system.

Solid models, surface models and faceted models can be imported into VisualMill, and a wide selection of tools and toolpath strategies to can be defined when generating toolpaths. These toolpaths can then be simulated and verified, and finally post-processed to the controller of your choice.

About This Guide

This guide is designed to introduce first-time users to VisualMill 4.0. The first part describes aspects of the user interface, machining strategies, and milling types. This is followed by several tutorials designed to familiarize you with the main features of VisualMill.

In addition to the information provided in this guide, see the context-sensitive online help for more comprehensive explanations. You can also look at the models included in the Tutorials folder.

VisualMill Configurations

VisualMill 4.0 comes in two configurations - VisualMill Basic and VisualMill (standard configuration).

VisualMill Basic is a general-purpose machining program targeted at the typical machinist. It is ideal for the rapid-prototyping, general machining, hobby and educational markets. The standard product is an advanced version, suitable for mold, die and tool making, woodworking, and other complex applications. This configuration is suitable for machinists with sophisticated manufacturing requirements.

Both configurations support 2½ and 3 axis milling, as well as drilling. The standard version also supports 4th axis milling. In addition, both versions can import Rhino, STL, IGES, DXF/DWG, VRML, and Raw Triangle files.

The Parasolid interface add-on module includes the Parasolid kernel. This enables you to import Parasolid geometry data from the native design files of any Parasolid-based CAD system, as well as SolidWorks and Solid Edge files.

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Computer Requirements

Intel Pentium compatible computer

Windows NT, 95, 98, 2000, ME, or XP with at least 64 MB RAM.

OpenGL-compatible graphics card, displaying at least 64,000 colors

Approximately 50 MB of hard disk space.

Installing VisualMill

To install VisualMill software, follow these instructions: Windows NT

1. Insert the CD-ROM into the CD_ROM drive.

2. Go to the Program Manager and select Run from the File menu.

3. In the Command Line box, enter D:\setup (where D is the letter of your CD-ROM drive) and follow instructions.

Windows 95, 98, 2000, ME, and XP

1. Insert the CD-ROM Disk into the CD_ROM drive.

2. The setup program will automatically launch once the computer detects the CD.

3. Follow the setup instructions.

Installing the VisualMill Security Key

VisualMill 4.0 ships with a hardware security device called the security key (or “dongle”). This is either a 25-pin connector that connects to the parallel port of your computer, or a USB key that plugs into any USB port on your computer. If you have any other device, such as a printer, connected through the parallel port, disconnect it and connect the VisualMill security key. Then reattach the connector of the original device on top of the security key; the device will continue to operate as before.

VisualMill will not operate correctly if the security key is not connected to the computer!

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Security Key Problems

If you have installed the dongle but VisualMill is not running properly, try restarting your computer. If that still does not work do the following:

1. For Windows NT / 2000 / XP, double-click on the setupx86.exe icon found in the Win_NT folder in the VisualMill installation folder (see the section below that describes the installation folder). For Windows 95 / 98 / ME, double-click on the sentw9x.exe icon in the Win_9x folder.

2. Select Functions / Remove Sentinel driver and click OK.

3. Double-click on the RainbowInstaller.exe icon in the VisualMill 4.0 folder, then click OK.

4. Restart your computer.

You can also download the Combo Installer from the Rainbow website (http://www.rainbow.com/support/eu_support.htm) and run the installation program. This will automatically install the drivers necessary for the proper operation of your security key.

If the above method does not work, download the Sentinel Medic from the Rainbow website (http://www.rainbow.com/support/eu_support.htm). Install it and run SproMedic.exe. Click Find SuperPro and send the following information that appears on the screen to [email protected], so that we can locate and fix your specific problem:

1. System Driver Info 2. Status 3. Description 4. Medic Says

VisualMill Installation Folder

VisualMill installation creates a main installation folder whose name and location you can specify during the installation process (or accept the default location of C:\Program Files\MecSoft Corporation\VisualMill 4.0). This folder contains the VisualMill executable and *.dll files. There are also several subfolders in the installation directory:

Data: Contains tool library files - DefaultEnglishTools.txt and DefaultMetricTools.txt. These files can be used as they are, or you can use them as templates and customize them with your own data. You will also find a speeds/feeds & material library file called FEEDSPEEDS. For more information on how to modify these tool library files, please refer to VisualMill’s online help.

Examples: Contains various example files that you can experiment with. There are files from other CAD systems you can import, as well as VisualMill files (*.vmp). The *.vmp files contain saved machining operations that you can study and modify.

Help: Contains the online help files used with VisualMill. You can open these files directly from this folder, or access them within VisualMill.

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http://www.rainbow.com/support/eu_support.htmhttp://www.rainbow.com/support/eu_support.htmmailto:[email protected]

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Posts: Contains the standard set of post-processor (*.spm) files. Additional post-processor files can be obtained from MecSoft Corporation. If you receive additional *.spm files, be sure to place them in this folder, so that VisualMill will recognize them.

Schema: Contains all the necessary files for loading Parasolid and Parasolid-based products, such as SolidWorks and SolidEdge files.

Tutorials: Contains a tutorial and several part files to help first-time users get familiar with VisualMill. These are similar to the tutorials presented in this guide, in onscreen format. To launch these tutorials, open the VisualMill4.0Tutorials.chm file, and use the table of contents or arrows to browse through the steps.

WIN_9x and WIN_NT: Contains the necessary files for the proper functioning of the hardware security key (dongle).

Running VisualMill

Click on the Windows Start button and select Programs. Point to the program group containing VisualMill. The name of this program group will be VisualMill 4.0, unless you specified otherwise during setup. Once you locate the program group, select it and then select VisualMill 4.0.

Registering VisualMill

After installation, you can run the full VisualMill version 50 times or for 30 days without registering the product. After this period, VisualMill will operate only in demo mode, without the ability to save part files or output toolpaths.

When VisualMill is invoked, you will see the Enter License Code window.

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The Tries Left field indicates the number of times you can run VisualMill before it starts operating in demo mode.

To obtain license codes you must register the product using the Web form available at www.mecsoft.com/register.htm. If you have purchased the product directly from MecSoft Corporation, you will have to provide the purchase invoice number before you can be licensed. If you have purchased the product through an authorized VisualMill reseller, please obtain the license codes from your reseller. In addition to this information make sure you also provide the Dongle ID that is shown on the registration screen. You can also access this form from within VisualMill by selecting Help / Register VisualMill.

VisualMill Display

If you are experiencing problems with the way VisualMill appears on the screen, try the following:

For Windows 98, ME, 2000 and XP:

1. Right-click anywhere on the desktop and select Properties from the menu.

2. Open the Settings tab and click Advanced.

3. Open the Troubleshoot or Performance tab and set Hardware acceleration to None.

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If you are still having problems, reinstall the video drivers of your video card. Or you can try another video card to see if the problem is specific to your card.

If VisualMill opens as a minimized window and closes when maximized (this happens on rare occasions, typically on computers with defective display cards), it is probably due to bad window coordinates stored in your computer’s registry. Try the following to eliminate this problem:

1. Press Windows + R button.

2. Type in regedit and click OK.

3. In HKEY_CURRENT_USER / Software, delete the VisualMill4.0 entry.

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VisualMill User Interface

VisualMill adheres to the Windows standard for user interface design. All functions can be accessed from the menus, and common functions are accessible via toolbar icons. Most user interface settings are modal - VisualMill “remembers” these settings and they remain active in subsequent operations unless you change them.

The main VisualMill user interface objects are described below:

File toolbar: Loads and saves part files

Machining toolbar: Provides steps to create toolpaths

Input toolbar: Used when yoto enter values manually

View toolbar: Tools to show and hide components, change view, zoom, pan, etc.

Browser: Displays geometry, machining operations, and tools

Notes: There are additional toolbars you can display by selecting V

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VCR toolbar: Simulates materialremoval

u need

Status Bar: Displays status of tool, units, snaps, and cursor location

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VisualMill Workflow The manufacturing process aims to successively reduce material from the stock model until it reaches the final shape of the designed part. To accomplish this, the typical machining strategy is to first use large tools to perform bulk removal from the stock (roughing operations), then use progressively smaller tools to remove smaller amounts of material (pre-finish operations). When the part has a uniform amount of stock remaining, a small tool is used to remove this uniform stock layer (finish operations).

This macto visuafeedback

Load Part & Stock

Create Roughing Operations

Simulate Material Removal

Create Pre-Finish Operations

Create Finishing Operations

Output Toolpaths to Machine

hining strategy is what you program using VisualMill. You can also simulate material removal lize how the stock model will look at any time during the process. This provides valuable that can help you choose the most appropriate machining strategy.

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Typical Scenario

Rough machining can be done by Horizontal Roughing (3 axis) or Pocketing (2½ axis) operations, using a relatively large flat end mill or an end mill with a corner radius. These rough operations can be followed by subsequent roughing operations, either using the same tool or a smaller tool.

The part can then be pre-finished by using Parallel Finishing or Horizontal Finishing (3 axis) or Profiling (2½ axis). Pre-finishing and finishing operations typically use ball end mills, with or without a side angle.

For complex 3D parts, additional finish operations may be necessary. For example, Parallel Finishing operation can be defined using a small ball tool with a fine stepover value.

Once all of the operations are completed, you can go back and review the operation sequence, re-order and/or change operations if desired, simulate the material removal, and post-process the toolpaths. The browser can be used to manage these operations.

Another powerful feature included in VisualMill is that of a Knowledge Database or K-Base. After creating an operation sequence for one part, you then save the operations and apply the same set of parameters and operation sequence to another part. This feature allows even novice users of VisualMill to machine parts quickly and easily.

Programming the Workflow

Once the part is loaded, the typical workflow is reflected in the layout of the icons in the Machining toolbar.

Note: This toolbar is slightly different in VisualMill Basic.

The steps are described below, and are demonstrated in the tutorials.

Set Cutting Direction: Defines the side of the geometry to cut.

Set Machine Zero: Aligns the part and stock geometry relative to the machine coordinate system.

Set Table Rotation Parameters: Defines machine table rotation axis and rotation center for use in 4th axis milling.

Create/Load Stock: Provides several methods for creating (or loading) the geometry representing the raw stock from which the part will be machined.

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Locate Part Within Stock: Positions the part geometry within the stock. For example, you can align the top face of the part with the top face of the stock.

Create/Select Tool: Opens a window in which you can define all the tools that will be needed in the machining operations.

Set Feeds/Speeds: Defines the feed and speed rates for cutting, rapid, engage, and retract tool motions.

Clearance Control: Sets the level above the part for safe rapid tool motion.

Select Regions: Provides several methods for selecting curves that will act as machining boundaries.

3 Axis Machining: Operations in which the tool can move in all three directions.

2½ Axis Machining: Operations in which the tool can move in X and Y only, at set Z levels.

Drilling: Drilling, tapping, and boring operations.

4th Axis Machining: Operations in which the tool can move in all directions, and the machine table can rotate. Not available in VisualMill Basic.

Toolpath Editor: Opens a window in which you can edit any line of toolpath code, insert special machine control commands, and make changes on groups of tool motions. Not available in VisualMill Basic.

Post Process: Sends the toolpath code to the machine.

Machining Operations

There are two major classes of machining operations that can be created in VisualMill - milling and drilling. Milling operations are used to mill out material to form shapes. Drilling operations are used to create holes. Both classes are essential in any manufacturing industry.

Milling operations can be categorized as 3 axis, 2½ axis, and 4th axis milling.

• 3 Axis: The tool can move simultaneously in all three directions.

• 2½ Axis: The tool can move in X and Y directions, while the Z level is fixed at set locations.

• 4th Axis: Rotates the machine table in order to machine parts that cannot be machined with simple 2½ axis or 3 axis operations.

These categories, and the available operations, within them are described in the sections to follow.

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3 Axis Operations

In this type of machining, the tool can move simultaneously in all three axes. This is appropriate for parts that have complex, curved, and non-vertical surfaces.

A typical machining scenario would be to first use Horizontal Roughing, the pre-finishing using Parallel Finishing and/or Horizontal Finishing. Once the part is at near net shape then fine detailed finishing could be performed by any of the re-machining or the region-based projection methods.

The available 3 axis operations are shown and described below.

Note: Only Horizontal Roughing and Parallel Finishing are available in VisualMill Basic.

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Horizontal Roughing

This is VisualMill’s principal method of roughing, also knows as waterline or constant Z cutting, in which the material is roughed out in horizontal layers. This type of machining is very efficient for removing large volumes of material, and is typically performed with a large tool. Roughing is typically followed by semi-finishing or finishing toolpaths.

Both part and stock geometry are used to determine the regions that can be safely machined. Three types of cutting patterns are available: Linear (parallel, zigzag lines), Stock Offset (spiral pattern within stock and part), and Part Offset (spiral pattern outside the stock and outside the part). Tool motions are shown for single Z levels in the pictures below.

Horizontal Roughing – Linear

Horizontal Roughing – Stock Offset (Pocketing)

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Horizontal Roughing – Part Offset (Facing)

Plunge Roughing

Not available in VisualMill Basic

Sometimes called drill roughing, the tool can cut in the Z direction only, not in X and Y. The tool makes a series of overlapping plunges to remove cylindrical plugs of material.

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Horizontal Re-roughing


This is used to create toolpaths in areas that were not machined by previous operations. Unmachined areas are determined by comparing the part to the stock remaining after the previous operation. Machining is performed in constant Z levels, one of which is shown below:

Plunge Re-roughing


Similar to Horizontal Re-Roughing, this method uses plunge motions to machine areas that were not machined by previous operations.

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Parallel Finishing

This is an efficient method of finishing or pre-finishing, typically used when part surfaces are relatively flat. A 2D linear zigzag pattern is generated on the XY plane above the part geometry. The tool moves along this cut pattern, following the contours of the part geometry below.

Pocket Finishing


This method is used for pre-finishing and finishing of pockets with sculpted bottoms and/or sides. The pockets are defined by regions, and successive inner offsets of these outer regions are generated. The tool moves along these offset curves while following the contours of the part below.

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Horizontal Finishing


This method is used for pre-finishing or finishing in constant Z levels, typically used when the part has large vertical surfaces and when Parallel Finishing will not yield satisfactory results.

Pencil Tracing


Used either for roughing, re-machining, or cleanup, the tool is driven along valleys and corners of the part. The system identifies all double contact or bi-tangency conditions based on the tool radius. It then creates cutting paths along these locations.

When used as a roughing operation, valleys and corners are relieves so that subsequent operations will not encounter large amounts of material in these regions, thereby reducing tool deflection and wear. When used as a cleanup operation, scallops that remain after finishing operations are removed.

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Valley Re-machining


This is used to machine corners and valleys that were inaccessible in previous finishing operations.

Plateau Machining


This method machines the tops of flat areas – areas that are within a specified angle from horizontal. This is typically used to re-machine areas that remain unmachined after a Horizontal Roughing or Horizontal Finishing toolpath.

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Parallel Hill Machining


This method machines steep areas. These are areas that are within a specified angle from vertical. This method is typically used when a Parallel Finish toolpath leaves scallops on steep areas. The cut angle is adjusted so that machining is always normal to the steep areas, thereby leaving minimal scallops.

Horizontal Hill Machining


Similar to Horizontal Finishing, this method machines in constant Z levels. However, machining can be restricted only to areas in the part that are steeper than a user-defined steepness angle.

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Radial Machining


This method is used as a finishing operation for areas that have annular pockets. You must specify one or more machining regions; the tool moves radially from the centroid of these regions.

Spiral Machining


This method is used for finishing areas that have circular or near-circular characteristics, such as pocket bottoms. You must specify one or more machining regions; the tool moves in a spiral pattern based on the centroid of these regions.

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Curve Machining


Suitable for machining isolated areas or shapes, this method machines along a curve. You must specify one or more machining regions, direction and cut pattern. The tool simultaneously follows the region and the contours of the part below.

Between 2 Curves Machining


Sometimes called flowline machining, this method machines between two open or closed curves. Using a pattern either parallel or normal to the curves, the toolpath makes a gradual transition from one curve to the other. This creates a blended toolpath that can be used to efficiently finish complex shapes.

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Reverse Post Milling


This feature loads toolpaths from APT CL files and ISO standard G Code files. You can use these toolpath motions to project the tool onto part surfaces. You can also load an existing toolpath in order to simulate it in VisualMill.

2½ Axis Operations

In 2½ axis toolpath, the tool can move in X and Y directions, but Z movements are limited to set levels. Because 2½ toolpaths do not relate to either part or stock geometry, machining regions must be selected; these define the boundaries of tool motions.

This type of machining is useful for machining prismatic parts – extrusions of curves along the Z axis. Because of its straight sides, a prismatic part can be machined by locking the tool at the first Z level, performing XY motions, then repeating for subsequent Z levels.

Using this class of machining, you can machine parts that are defined only by 2D curves. 3D part geometry can be present, though it is not necessary.

As with 3 axis operations, a typical machining operation would involve roughing then finishing. Unlike the more complex 3 axis parts, detailed finishing is typically not necessary for prismatic parts. Roughing

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is typically performed using a combination of Facing and Pocketing operations, and Profiling is used for finishing.

The available 2½ axis operations are shown and described below.

Note: Facing is not available in VisualMill Basic.

Facing


This method machines closed regions as if they were completely enclosing material to be removed. This means that the tool can approach the material from outside the outer regions, creating reverse pockets.

This example uses multiple regions – the rectangle is the outer region, and each letter is an inner region. Some letters have nested regions; these are treated as islands (areas to avoid).

Note: The outer region should encompass the stock. You can easily create this type of region by selecting Curve / Bounding Region / Stock Bounding Region.

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The toolpath looks like the following:

The stock simulation:

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Pocketing

This method machines closed regions as if they were pockets - completely enclosed by inner and outer regions. The tool cannot go beyond the outer region, and cannot go within inner regions. This is unlike Facing, in which the outermost region is considered to enclose material to be removed.

This example uses similar regions as the previous Facing example, but the outer region is within the stock limits.

The toolpath looks like the following:

The stock simulation:

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Profiling

This method machines open and closed regions by tracing along one side of their contours. You can define offsets so that the tool makes multiple passes relative to the regions.

Profiling can be used as a finishing operation after a Pocketing or Facing toolpath, or it can be used alone.

Engraving

Typically used for engraving text or logos on a finished mode, this method machines open or closed, 2D or 3D regions by tracing along the contours. This method is similar to Curve Machining, in which the tool is projected onto the part surfaces below the regions being followed. You can use a conical tool such as a drill tool for engraving.

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Drilling Operations

These operations are used to create holes in the part, including drill holes, counter sunk holes and through holes. Tapped and bored holes can also be created.

The following drilling operations are available:

Note: Tapping, Boring, and Reverse Boring are not available in VisualMill Basic.

Drilling

The following drill cycles are available:

• Standard: Used for holes whose depth is less than three times the tool diameter.

• Deep: Used for holes whose depth is greater than three times the tool diameter, especially when chips are difficult to remove. The tool retracts completely to clean out all chips.

• Counter Sink: Cuts an angular opening at the end of the hole.

• Break Chip: Similar to Deep drilling, but the tool retracts by a set clearance distance.

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Tapping


A Tap cycle is used to drill threaded holes in the part, clockwise or counter-clockwise.

Boring


A Bore cycle is used to form shapes inside a hole. The following boring cycles are available:

• Drag: The tool is fed to the specified depth at the controlled feed rate. Then the spindle is stopped and the tool retracts rapidly.

• No Drag: The tool is fed to the specified depth at the controlled feed rate. It is then stopped to orient the spindle, moved away from the side of the hole and then retracted.

• Manual: The tool traverses to the programmed point and is fed to the specified depth at the controlled feed rate. Then the tool stops and is retracted manually.

Reverse Boring


This is simply a Bore cycle in the reverse direction. The spindle is oriented to the specified angle and moves rapidly to the feed depth and moved to the part. The spindle is turned on and the cycle is started.

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Fourth Axis Operations


Fourth Axis operations are used to machine parts that cannot be machined with simple 2½ axis or 3 axis operations. During 2½ and 3 axis milling, the tool remains vertical and the table is fixed. This means that areas of the part that cannot be accessed from above cannot be cut.

There are generally two ways to use 4th axis operations – indexed or continuous mode. The Set Table Rotation Params command enables you to set the rotation axis and origin for the table.

• Indexed mode: Use 3 axis operations to mill one half of the part, flip the table using a Rotate Table command, and then mill the other half. You are not restricted to 180-degree rotations.

• Continuous mode: The part is rotated continuously so that the tool is always normal to the axis of rotation. This is useful for machining multi-sided parts.

The available 4th axis operations are shown and described below.

4th Axis Parallel Finishing

In this method, the tool is always normal to the axis of table rotation (continuous mode). The tool can move in all directions while the table rotates continuously. The tool motions can be parallel to or normal to the rotation axis.

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4th Axis Engraving

Similar to 3 axis engraving, this method machines text or logos by following the contours of the selected regions. Continuous mode is also used here.

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Tutorial 1: 3 Axis Milling

In this tutorial, you will create 3-axis milling toolpaths to manufacture a designed part.

The stepped instructions are accompanied by explanatory and introductory text. Reading this text will help you understand the tutorial methodology and provide information about additional options available. However, if you prefer to work straight through the steps without any additional reading, look for the following symbol:

Don’t forget to save your work periodically! You may want to save the file under a different name so that the original file will be preserved.

The File Toolbar

Before beginning, the first commands you should know are on the File toolbar. These commands are used to load and save files, and can also be accessed from the File menu.

New: Creates a new file.

Open: Loads part geometry into VisualMill. This geometry is typically imported from other CAD formats.

Save: Saves the current file as a *.vmp file. We recommend saving your work periodically, to avoid losing data.

Loading a Part Model

“Part” refers to the geometry that represents the final manufactured product. You can create parts within VisualMill, but it is more typical to import geometry created in another CAD system.

You can import solid models of standard Parasolid XT format, or Stereo-Lithography (both ASCII and binary) format files. Surfaces can be imported from IGES or Rhino 3DM. Faceted (triangulated) models can be imported from VRML, Raw Triangle, DXF / DWG facet data, or Rhino Mesh. Non-faceted geometry, once imported, is immediately converted and stored as triangulated data.

Imported geometry is stored internally as a VisualMill part file. This allows for much faster part loading time.

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To load a part: 4. Select File / Open, or click the Open Part File icon from the File toolbar.

5. From the Open dialog box, select the dumbells.vmp file from the Tutorials folder in the VisualMill installation folder.

The imported part appears as shown below.

Note: Depending on your settings, you may also see the browser, construction grid, coordinate axes, and/or regions. You can use the options in the View menu or View toolbar to adjust what appears. You can change the background color and color of the part by selecting Preferences / Color Preferences and clicking the relevant color box. The browser can be displayed or hidden by selecting View / Toolbars / Browser.

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View Toolbar

The View toolbar is used for view and display manipulation. By default, it appears vertically along the left side of the screen, but you can dock it anywhere.

Each of the view functions is described below:

Zoom In: Doubles the displayed size.

Zoom Out: Halves the displayed size.

Zoom Box: Zooms in on an area you specify by defining a rubber-banded rectangle.

Center View: Centers the view about a selected point.

Fit View: Fits the entire part into display extents.

Repaint View: Repaints, or refreshes, the view.

Dynamic Pan View: Pans the view by holding and dragging the mouse.

Dynamic Zoom View: Zooms the view by holding and dragging the mouse. Move the mouse up to zoom in, move the mouse down to zoom out.

Dynamic Rotate View: Rotates the view by holding and dragging the mouse. The rotation follows the mouse movements as if there were an imaginary trackball at the center of the view.

Dynamic Rotate View About Z: Rotates the view about the Z axis and the origin point, by holding and dragging the mouse.

Top View: Displays the top view - the XY plane.

Right View: Displays the right view - the YZ plane.

Front View: Displays the left view - the XZ plane.

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Iso View: Displays the model in isometric projection.

Hide Part Model: Toggles the display of part geometry.

Shade Part: Toggles the display of part geometry between shaded and wireframe modes.

Hide Stock: Toggles the display of the stock geometry.

Reset Stock Color: Resets the stock color after simulation to the original color of the stock. During simulation, the cut stock takes on the Cut Stock color (defined in Preferences / Color Preferences). If you reset the stock color, only the results of the next toolpath simulation will be shown in the Cut Color.

Hide Machining Regions: Toggles the display of regions.

Display Grid: Toggles the display of the construction grid.

Hide Toolpath: Toggles the display of the toolpath associated with the current machining operation.

Display Next Z: Displays the toolpath for each level. This button is only active for horizontal milling operations.

Hide Coordinate Axis: Toggles the display of the coordinate axes.

Creating the Stock

“Stock” represents the raw stock from which the part will be manufactured. Stock geometry can either be created within VisualMill or imported from an external file.

You can import Parasolid XT solid models and STL solid models (ASCII and binary) for stock geometry. Surfaces can be imported from IGES or Rhino 3DM. Faceted (triangulated) models can be imported from VRML, Raw Triangle, DXF / DWG facet data, or Rhino Mesh.

Stock can also be created within VisualMill by entering coordinates or as the bounding box of the part or a toolpath. You can also define stock as a uniform offset of the part geometry, to simulate casting or forging raw stock model.

Note: You must define a stock model before creating Horizontal Roughing and Plunge Roughing operations. All other operations can be created without first creating a stock model.

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To create the stock: 1. Select Stock / Part Box Stock, or click Create/Load Stock from the Machining toolbar and

select Part Box Stock.

This option enables you to create a stock box that encloses all of the part geometry (bounding box).

2. In the Part Bounding Stock Box window, you can expand the bounding box by entering offset values. For the purposes of this exercise, do not enter any offsets. Click OK.

3. If you are asked whether you want to display the stock, click Yes.

4. The stock model is created. To display the stock, make sure the Hide Stock toggle icon in the View toolbar is not pressed.

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The stock is displayed as a box over the part. Its color can be set in the Color Preferences.

Tip: Stock is used for simulation, and its display involves data-intensive rendering. This can slow down VisualMill’s performance. Therefore, we recommend turning off the stock display when not needed.

Browser

The browser appears to the left of the screen by default, and can be displayed or hidden by selecting View / Toolbars / Browser. Like all toolbars, you can drag it to another location by clicking and dragging it by one of its corners. You can also resize it by dragging one of its sides.

Standard Windows operations can be used here, when appropriate. You can drag and drop items to change their order, and Ctrl+C (copy), Ctrl+X (cut), and Ctrl+V (paste) can be used. Dragging an item outside the browser will delete it. Items can be renamed here as well.

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The browser contains the following three tabs:

Geom Tab


The geometry manager displays the three types of geometry that can be created and manipulated in VisualMill: Part, Stock and Regions.

The first icon represents the Part. For an imported part, the full path is indicated. If the part consists of surfaces, each surface is represented as a Mesh. You can click on each mesh name to highlight its corresponding surface.

The Stock icon indicates the type of stock. You can double-click to create a different type of stock, or right-click to or delete the stock or export it to an *.stl file. A red star next to this icon indicates that the work-in-progress stock model corresponding to this operation needs to be created.

The last section is Regions. These are curves in the model that are used to define machining boundaries. You will work with regions in the next tutorial.

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Mops Tab

“Mops” stands for Machining Operations. All toolpaths you create are listed here, in order of creation.

Within each toolpath folder you can edit its various components, such as tool, regions, or cut parameters, by double-clicking the relevant icon. Right-clicking on a toolpath name provides several options, including simulation, generation, and post-processing.

If you make any changes to a toolpath’s parameters, the yellow folder icon for that toolpath will turn red. This indicates that the toolpath needs to be regenerated.

Tools Tab

This tab lists all tools currently defined in the file.

If you have created machining operations, the toolpath will appear in the Tools tab underneath the tool it uses.

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You can rename and delete tools, but you cannot delete a tool that is used in a toolpath. Double-click a tool icon to edit its parameters.

Creating Tools

VisualMill supports ball mills, flat end mills, corner-radius or bull nose, and taper end mills, in addition to drills, taps and bores. For each tool you can specify standard APT parameters: diameter, corner radius, taper angle, flute length and tool length. Flute length is the cutting length, and Tool Length is the total length of the tool up to the tool holder. All defined tools can be viewed in the Tools tab of the browser. You can also save a set of tools to an external folder that can be loaded in other files.

To create the roughing tool: 1. Select Tool / Create/Select Tool, or click the Create/Select Tool icon on the Machining

toolbar.

2. In the Select/Create Tools window, click the Flat End Mill tab.

Note: This window looks slightly different in VisualMill Basic.

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Leave the default values as they are and click Save as New Tool. The tool will be created and its name (FlatMill1, by default) will be displayed in the tool list.

To create the pre-finishing tool: 1. In the Select/Create Tools window, click the Ball End Mill tab.

2. Again, accept the default tool parameters and click Save as New Tool.

You have created the BallMill1 tool that has a diameter of 0.5 inches.

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To create the pencil trace tool: Pencil tracing is usually performed with a bull nose tool with a smaller diameter than the pre-finish tool.

1. While still in the Ball End Mill tab, change the tool diameter from 0.5 to 0.25 inches.

2. Change the tool name to BallMill2.

3. Click Save as New Tool.

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To create the finishing tool: Finishing is typically performed using a ball mill with a diameter much smaller than that of the pre-finishing tool.

1. While still in the Ball End Mill tab, change the tool diameter to 0.125 inches.

2. Change the tool name to FineFinisher.

3. Click Save as New Tool.

4. Click OK to close the window.

5. Now that all tools have been created, click the Tools tab in the browser. All the tools are listed.

If the file had tools already defined, they will be displayed here as well. But only the four tools you just created will be used.

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Note: You can double-click on any tool to open its definition window. This is an easy way to make changes, if needed.

6. A group of tools can be saved to a library file for future use. Select Tool / Save Tool Library.

7. In the default folder (should be Tutorials, which contains the part file), assign the name Dumbells_Tools. The default extension is *.csv (comma-separated values), which means the file can be opened and edited as a spreadsheet or in a text editor. Click Save.

8. Right-click on the Tools header in the browser and select Delete All.

9. To replace the tools, select Tool / Load Tool Library. Select the *.csv file you just saved, and the tools reappear in the file.

Setting Feeds and Speeds

You can set toolpath feeds and speeds and customize these settings for later use. The Set Feeds / Speeds icon on the Machining toolbar accesses these parameters.

You can assign values for the following:

Spindle Speed: The rotational speed of the spindle, in RPM.

Cut Feed: The feed rate used when the tool is cutting, in inches per minute.

Engage Feed: The feed rate used when the tool is approaching the part. By default this value is 75% of the Cut Feed.

Retract Feed: The feed rate used when the tool is retracting from the part. By default, this is equal to Engage Feed.

Transfer Feedrate: Specifies the feedrate of transfer motions (air motions). You can either use the Rapid setting of the tool, or set a custom feed rate.

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Customizing Feeds and Speeds

You can customize the feeds and speeds based on the stock material, tool material, and operation type. Then your settings can be saved to a file for future use.

A default feed / speed table is in the FEEDSPEEDS file (no extension), located in the Data folder. You can edit this file and then store your values in an ASCII external file. The format for this file is shown below:

TYPE

{

STOCK_MATERIAL TOOL_MATERIAL SURFACE_SPEED UNITS FEED/TOOTH UNITS MACHINABILITY UNITS

STOCK_MATERIAL TOOL_MATERIAL SURFACE_SPEED UNITS FEED/TOOTH UNITS MACHINABILITY UNITS

......

}

Example:

FaceMilling

{

aluminum-cast carbide 900 fpm 0.0200 in 4.0 ci/min/hp

aluminum-cast hss 650 fpm 0.0160 in 4.0 ci/min/hp

aluminum-plate carbide 900 fpm 0.0200 in 4.0 ci/min/hp

aluminum-plate hss 650 fpm 0.0160 in 4.0 ci/min/hp

}

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You can load values from this table by selecting Feeds/Speeds / Load Feeds/Speeds.

Type, Stock Material, and Tool Material are parameters in the external file. The Surface Speed and Feed/Tooth values are calculated based on these fields. Tool Diameter and # of Flutes are taken from the currently active tool (if any) and are used to calculate Spindle Speed and Cut Feed. By changing parameters of the active tool, you can use this window as a feed/speed calculator.

The current Cut, Engage, Retract, and Transfer Feeds are displayed in the top-right box. If you want to modify these values based on the calculated values on the left side, copy the values to the relevant fields on the right side and click OK to update.

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To set feeds and speeds: 1. Select Feeds/Speeds / Set Feeds/Speeds or click the Set Feeds/Speeds icon on the Machining

toolbar.

2. Leave the spindle speed as is and change the Cut Feed to 30 in/min. Set the Engage Feed and Retract Feed to 20 in/min. Click OK.

These feeds and speeds will be used during the post-processing of the toolpath.

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Status Bar

The Status Bar, located at the bottom of the screen, is used to display information about the current activities.

The left-most field displays the current command and any prompts or help information associated with this command. If you place the cursor over an icon, its description will appear here.

The next field indicates the active tool, if any. The name of the tool, followed by the diameter and corner radius, is displayed.

The next field indicates the progression of toolpath simulation (“Goto”), displaying the number of the motion being simulated. When the simulation is complete, the last motion number will be displayed.

The next three fields (Snap, Ortho, and Osnap) display snap modes for point input. These fields can be turned on and off by clicking in them.

• Snap: Toggles the ability to snap to grid points.

• Ortho: In Ortho mode, all lines are horizontal or vertical.

• Osnap: Object snap - toggles the ability to snap to points on the model and on regions and curves.

The second to last field displays the work units – inches or mm.

The last field shows the current location of the cursor as X, Y, Z coordinates. These values update as the cursor moves.

Creating the Horizontal Roughing Toolpath

In this type of toolpath, VisualMill uses stock geometry and part geometry to determine the safe machining region at each user-specified Z level. The safe machining region is the region in which the tool can safely traverse removing stock. Once this machining region is determined, a tool traversal pattern such as a zigzag or offset machining cut pattern can then be applied to remove stock.

Note: For 3 axis milling, you can also create and activate regions that act as machining boundaries. An example would be if you wanted to machine only one surface; you could define a region around that surface so that no other areas will be milled.

Regions are curves that already exist in the model, or curves you create within VisualMill. In the Geom tab of the browser, you will see that one region already exists in this file. Regions will not be used in Tutorial 1, since they are not required for 3 axis milling. However, they are required for 2½ axis milling, so you will learn about them in Tutorial 2.

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To create the horizontal roughing toolpath: 1. First you must activate the tool to be used. Select Tool / Create/Select Tool or click the

Create/Select Tool icon on the Machining toolbar.

2. Select the Flat End Mill tab, pick FlatMill1 and click OK. FlatMill1 is now the active tool, and is listed in the Status Bar.

3. Select 3-Axis Milling / Horizontal Roughing, or click the 3-AxisMaching icon on the Machining toolbar and select Horizontal Roughing.

The Horizontal Roughing window opens, in which you can set various parameters for the toolpath.

4. Click the Cut Parameters tab. At the top of the window are Global Parameters – Intol, Outol, and Stock.

• Stock: The thickness of the layer that will remain on top of the part after the toolpath is complete. Roughing operations generally leave a thin layer of stock, but for finishing operations this value is zero.

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Intol and Outol are allowable deviations (tolerances) from the actual part geometry plus the Stock layer (if any).

• Intol: Inward tolerance - the maximum thickness of material that can be removed from the Stock layer.

• Outol: Outward tolerance - the maximum thickness of material that can remain above the Stock layer.

5. Leave the Global Parameters as they are, but change the Cut Direction to Mixed. This enables the tool to cut either up or down, so that the tool does not have to retract each time the direction changes. Minimizing the number of tool retractions creates a cleaner toolpath.

6. Click the Cut Levels tab and set the Bottom cut level to 0.0. (You must first check the box in order to activate the field.)

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7. Leave the remaining parameters in the other tabs as they are, and click Generate, located at the bottom of the window.

The window will disappear and an hourglass cursor will appear on the screen. When the calculation is complete, the roughing toolpath will appear.

In this toolpath there are so many cut levels that the display is too dense for you to decipher much detail. It is helpful to view the toolpath one level at a time.

8. Click Display Next Z on the View toolbar. All Z levels are listed, and you can click the desired level to see its tool movements.

9. Close the Z Level Display window.

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10. Look in the Mops tab of the browser, where you can see the toolpath you just created.

VCR Toolbar

The VCR commands are used for toolpath simulation.

The VisualMill simulator enables you to view your toolpath in action, reflecting what the actual model would look like after machining. Simulation can also be used to catch errors.

The cut stock can also be visually compared with the part model to indicate any areas of uncut or overcut material.

For simulation to work, you must have stock geometry defined, and the stock must be displayed.

Simulate: The simulation will be run for the entire toolpath, and the end result of the material removal will be displayed.

Simulate Until: Shows removed material for all operations up to and including the currently selected one.

Step Increment: Controls the number of steps that are simulated each time you click Simulate Each Step. You can choose one of the numbers in the drop-down list or enter a number.

Simulate Each Step: The simulation will be performed for a specified number of toolpath motions, specified in the Step Increment box.

Simulate with Display: The entire simulation will be run in animation, including a symbol for the tool.

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Simulate with Display Each Z Level: Simulates the toolpath for each successive Z level. This is applicable only for machining methods that use multiple Z levels for machining, such as Horizontal Roughing and Pocketing.

Compare Part/Stock: Performs a visual comparison of the stock model against the part model. You can color-code areas based on the amount of material remaining or overcut.

Note: You can press the Esc key to interrupt the simulation.

Simulating the Horizontal Roughing Toolpath

Now that the first toolpath has been created, you can simulate it.

There are two simulation models in VisualMill – 3 axis and 4 axis. You can choose the simulation model by selecting Preferences / Machining Preferences.

The 3 axis model is very fast. It uses a grid to represent the stock, so it can only be used for 2½ and 3 axis simulations (in which the bottom of the part is squared off). The 4 axis simulation is a true simulation (uses the true stock shape), and may therefore be slower than the 3 axis model.

To simulate the toolpath: 1. Be sure you are using the 3 Axis Simulation Model. Verify this in Preferences / Machining

Preferences.

2. Click Hide Toolpath on the View toolbar to clear the toolpath from the display.

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3. On the View toolbar, make sure the Hide Stock icon is not pressed. You need to see the stock in order to see the simulation.

4. On the VCR toolbar, click the Simulate icon.

This will start the simulation, which will stop when all of the tool motions have been processed. During the simulation you will see the count of the toolpath motions dynamically displayed in the Status Bar.

Note: You can also try clicking Simulate Each Step to simulate smaller numbers of motions at once, Simulate with Display to see the tool moving while removing material, or Simulate with Display Each Z Level to see levels removed one at a time.

Once the simulation is complete, the cut stock model will be displayed. This cut model can be used as input stock geometry for simulating the toolpath of subsequent machining operations.

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Tips: To get a better view during simulation, you can also turn off the display of the part. You can change the color of the cut stock by selecting Preferences / Color Preferences and clicking the color box for Cut Stock Color.

Creating the Pre-Finish Toolpath

Once the roughing toolpath is generated, a pre-finish toolpath can be created to remove the steps left by the roughing process, and to bring the stock closer to the part. There are several methods of generating pre-finishing toolpaths; in this exercise will use the Parallel Finishing method.

To create the pre-finish toolpath: 1. Make sure both the stock and toolpath are displayed.

2. Open the Select/Create Tools window, click the Ball End Mill tab, and select BallMill1. Click OK to make this the active tool. (You could also double-click the tool name.)

3. Select 3 Axis Milling / Parallel Finishing, or use the 3 Axis Machining icon.

We will use all default settings except for the stock value. Pre-finishing is typically done so that there is a uniform thickness of stock left on the part, to be removed by the final finish path.

4. Click the Cut Parameters tab, and enter 0.025 in the Stock field.

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5. Click Generate to calculate the toolpath. This toolpath uses a linear zigzag pattern.

To simulate the pre-finish toolpath: 1. Turn off the toolpath display, but make sure the stock is displayed. Hide the part.

2. On the VCR toolbar, click Simulate Until.

The results show how the stock will look after the pre-finishing toolpath is run.

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Creating the Pencil Tracing Toolpath

Not available in VisualMill Basic. Basic users – proceed to “Creating the Finish Toolpath.”

In Pencil Tracing, VisualMill automatically determines all areas of the part where a tool would have more than one contact position. These areas are typically in valleys and corners. The tool is then moved along these areas to remove material.

This is a very efficient method to stress-relieve corners and valleys before running a pre-finish toolpath. It can also be used as a cleanup operation to remove scallops left in these areas after finishing operations. Pencil tracing is typically performed with a ball end mill.

To create the pencil tracing toolpath: 1. Display the toolpath, and make BallMill2 the active tool.

2. Select 3 Axis Milling / Pencil Tracing.

3. In the Pencil Trace Cut Parameters tab, set Stock to 0.01. Leave all other parameters at their default settings.

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4. Click Generate.

Tip: Pencil tracing is typically performed with ball end mills. If there are any fillets in the model, make sure that the pencil tool radius is slightly larger than the maximum fillet radius. This ensures that the tool will be driven along all of the fillet surfaces.

To simulate the pencil tracing toolpath: 1. Hide the toolpath and display the stock.

2. As you have probably noticed, after the simulation is complete the cut areas of the stock are colored using the specified cut color. On the View toolbar, click Reset Stock Color, which returns the entire stock to the original stock color.

This gives a clear view of cut areas in subsequent cut simulations.

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3. On the VCR toolbar, click Simulate. Notice how the pencil trace toolpath removes the scallops along the valleys of the part.

Creating the Finish Toolpath

In finish machining, all of the remaining stock is removed to create the final net shape. This example will use the Parallel Finishing method again.

Finish machining is almost always performed with a ball end mill. Here we will use the final finish tolerance as well as use a very fine stepover value.

To create the finish toolpath: 4. Activate the FineFinisher ball end tool.

5. Select 3 Axis Machining / Parallel Finishing.

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6. The parameters are already set to finish tolerances, but we will change a few items:

Change the Stock value from 0.025 (used in the previous toolpath) to 0.0. This leaves no layer of stock over the resulting part.

Change the Angle of Cuts to 90 degrees, relative to the previous pre-finish cuts. This will create a better finish on the part.

Change the Stepover Control value from 25% to 10% of the tool diameter. This reduces the distance between passes, making for a better finish.

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7. Click Generate.

8. Reset the stock color, and simulate.

The final part is displayed, and in the Browser you can see all the toolpaths you created.

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9. Click the Tool tab in the browser to see each tool, linked to the toolpath that uses it.

Post-Processing

Once the toolpath has been generated, it can be post-processed to a specific machine controller. VisualMill Standard comes with a set of post-processors to choose from. Each post-processor is represented by an *.spm file, all of which are located in the Posts folder under the VisualMill installation folder.

You can post-process an individual toolpath, or all toolpaths at once. For an individual toolpath, right-click on its name in the Mops tab of the browser and select Post. You can also click Post Process on the Machining toolbar.

The entire list of toolpaths can be post-processed by right-clicking the root folder in the Mops tab and selecting Post All.

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Set Post Options

Some post-processor options can be set by selecting Post Process / Set Post Options.

By default, VisualMill performs interactive post-processing. In other words, VisualMill launches the post-processor and waits for the post-processor to complete. You can check Post Process in Batch Mode to tell VisualMill not to wait for the completion of the post-processor. You can also output the list files and display the selection dialog for each post processing operation.

During interactive post-processing, VisualMill launches a text editor to display the output file. By default, Notepad is used, but you can specify a different program.

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Post Processor Generator

You can select Post Process / Post Processor Generator to edit post processor parameters, and set up your own post-processors.

Click a post processor to change or copy, and click Edit.

The editable parameters can be found on the various tabs. To create a new post-processor, define the parameters and click Save As. A new *.spm file will be created in the Post folder.

You can also output the toolpath in an APT standard Cutter Location (CL) file. APT is a widely accepted Numerical Control Machine standard. This CL file can then be used to create a machine specific post-processed output through any of the many commercially available APT post-processors.

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To create the post-processed output: In this exercise we will post-process all of the toolpaths at once.

1. In the browser, click the Mops tab. The toolpaths are shown here collapsed.

2. Right-click on the root folder (Machining Operations) to open the popup menu. Select Post All.

3. Browse to the desired output directory and assign a file name for the output. The default extension is *.nc. Then double-click on the post-processor you want to use (such as Fanuc 1).

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4. When complete, the post output file will open in the default text editor (Notepad by default). This file contains all the G-code for your toolpaths.

Note: You can post individual toolpaths by right-clicking on their name in the Mops tab and selecting Post. The Post-Process icon on the Machining toolbar can also be used. To post multiple toolpaths, select each toolpath while keeping Ctrl pressed, right-click, and select Post All.

Post-Processor Problems

If only two built in posts (APT CLS and Roland CAMM GL) are displayed in the selection dialog, then your Post folder is not set correctly. Try the following:

1. Click Browse on the Select Post Processor window.

2. Select the Posts folder located in the VisualMill installation folder.

If nothing happens when the toolpath is posted, try the following:

1. Select Post Process / Set Post Options.

2. Make sure Show Selection dialog when Post Processing is checked.

3. Make sure Post Process in Batch Mode is not selected.

4. Make sure Output Listing Files is not selected.

5. Post the machining operations, making sure you are browsing to the Post folder in the VisualMill installation folder. For the output file at the bottom, make sure there is a valid file name (valid path).

End of Tutorial 1!

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Tutorial 2: 2½ Axis Milling Operations

This exercise uses the file spanner.vmp, located in the Tutorials folder. Use File / Open to load the part.

This part is suitable for 2½ axis milling because it is prismatic – it is a straight extrusion of curves in the XY plane. The solid geometry is not actually necessary for programming this part, but it is helpful when visualizing the process.

Creating Tools and Stock

Before any operations can be performed, you must define the milling tools and the stock geometry.

To create the 2½ axis milling tools: 1. Create and save the following three tools:

Flat end mill named Rougher with a diameter of 0.5 inches

Flat end mill named Finisher with a diameter of 0.25 inches

Ball end mill named Ball Rougher with a diameter of 0.5 inches

2. Open the Tools tab of the browser to see the tools listed.

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3. Right-click on the Tools header and select Information. This displays a table listing the properties of all the tools you’ve defined.

To create the stock: 1. Select Stock / Box Stock. The dimensions of the bounding box are automatically calculated.

Change the height to 1.25 from 1.0, so that there will be 0.25 inches of stock material above the part. Do not click OK yet.

2. The stock box is automatically located at the corner of the bounding box, as you can see from the calculated (Xc, Yc, Zc) coordinates. This is the correct location, but for the sake of the tutorial, change the coordinates to (0,0,0).

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3. Click OK. This creates a box that is the right size, but located in the wrong place.

4. To locate the stock correctly, click Locate Part Within Stock on the Machining toolbar.

5. Check Move Stock (so that the stock will move to meet the part) and Bottom so that the bottom face of the stock will align with the bottom face of the part. Check Center to center the stock about the part.

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6. Click Apply to locate the stock correctly.

Creating Regions

Regions are curves that already exist in your model, or curves you create within VisualMill, using the Curve tools. Regions serve different purposes in 2½ and 3 axis milling.

In 3 axis milling, regions are used, when necessary, to define the machining boundary. The center of the tool remains inside the region while following the contours of the part. For example, if you define a region surrounding one surface, only that surface will be milled.

In 2½ axis milling, however, regions determine the entire area to be milled. Part and stock geometry are not considered, and the tool always moves at a fixed Z level. Therefore, regions act as the drive curves, and their geometry is projected onto the stock.

Regions must be selected (activated) in order to be used in an operation. Creating a region does not make it active; you must use one of the Select Regions tools before creating the toolpath.

Note: If a region is not defined for finishing operations, the part silhouette is automatically identified and used as a containment region for the tool. For roughing operations, the stock geometry determines the constraints on the tool location.

The Create Regions toolbar contains several tools for creating regions:

Each tool is described below:

Point: Creates a point by selecting it on screen or entering its coordinates. Points are used as references for other region tools.

Mid Point: To create a point at the midpoint of a line, click this icon and select the endpoints of the line.

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Center Point: To create a point at the center of a circle, click this icon and then select three points of the circle.

Line: Creates a line by selecting two points.

Polygon/Polyline: Select the vertices of the polygon. If you want to close the region, move the cursor close to the start point of the region and select it. Right-click to finish.

Rectangle: Creates a rectangle by selecting its opposite corners.

Circle: Creates a circle by selecting its center and a point on the circumference.

Circle by Start Point and Diameter: Creates a circle by selecting two opposite points (diameter endpoints).

3 Point Circle: Creates a circle by selecting three points on its circumference.

Arc by Center, Start and Angle: Creates an arc by selecting the arc center, start point, and end point.

Arc by 3 Points: Creates an arc by selecting the start point, a point on its circumference, and the endpoint.

Auto Chain Edges: Creates a region along a chain of edges. This is useful for creating a region along the outer boundaries of a surface. Select one edge, and all edges in the chain are automatically selected.

Manually Chain Edges: Creates a region along a chain you define manually. Select an edge, and a vector will be displayed at the end of the edge. Then select the edge closest to the start of this vector. Continue until either the region is closed, or right-click to finish.

Part Bounding Box Region: Creates a rectangular region along the XY plane of the part’s bounding box.

Stock Bounding Box Region: Creates a rectangular region along the XY plane of the stock box.

Undo: Deletes the last point selected to create the region. This is useful when using the Polygon/polyline tool.

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To create the regions: Because 2½ axis milling does not relate to part or stock geometry, milling regions must be created to define the machining boundaries.

1. Hide the stock, and make sure Hide Regions is not pressed.

There are four regions already defined for the part. You can also see the regions in the Geom tab of the browser (not available in VisualMill Basic).

These regions are provided so that you can see the regions that need to be defined for the part. We will recreate them manually.

2. Select the Region header in the browser, right-click, and select Delete All Regions. (You could also delete each region individually by right-clicking and selecting Delete, or by dragging a region outside the browser area.)

VisualMill Basic users – select Edit / Select / Single, press Ctrl, and use the cursor to manually select all four regions. They turn black when selected. Then select Edit / Delete.

Note: If you need to redraw the display, select View / Repaint.

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3. If the Create Regions toolbar is not displayed, select View / Toolbars / Curves/Region Bar. This toolbar appears vertically to the right of the screen.

4. Make sure the Osnap indicator is on in the Status Bar. This enables you to snap to points on the part.

5. Select Curve / Chain Edges / Auto Chain Edges, or click the icon on the Create Regions toolbar.

6. With this option, you can select one edge and the entire chain of edges is selected. Use this to create regions around the two chains of edges shown below.

Tip: If you obtain the wrong chain (you might select a vertical surface boundary rather than the desired chain), click again in a different place to create the correct region. Then you can simply delete the unwanted region, or leave it if you prefer.

7. The next region is along the circular hole. Select Curve / Circle / 3 Point Circle or select the icon on the Create Regions toolbar.

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8. Select any three points along the top circle to create this region.

9. The final region is a rectangle surrounding the part. Select Curve / Bounding Region / Part Bounding Region or click the icon on the Create Regions toolbar.

10. Because the region should extend slightly past the part extents, enter X and Y offsets of 0.25 inches.

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