mastercam 2020 reference - harvard university

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MasterCAM 2020 Reference Basic Navigation Zoom Rotate Pan Managing Geometry Merge Geometry Select Geometry Move Geometry Delete Geometry Visibility Managing Levels Layers vs. Levels Level Manager Managing Planes WCS + Tplane + Cplane Plane Manager Creating a Plane Managing Operations What is a Toolpath? Toolpath Manager Hierarchical Organization Operation Components Selecting an Operation Ordering Operations Toolpath Visibility Toolpath Generation Defining Parameters Parameters | UI Inconsistencies Parameters | Surface + Chain + Point Tool Selection Planes Machining Heights Parameters | Surface + Chain Stock to Leave Stepover Stepdown Cutting Method Machining Angle Parameters | Surface Only Depth Limits Roll Tool Tool Containment Parameters | Chain Only Compensation Lead In / Out Multi Passes Break Through Tabs Assigning Geometry Surface Operations Chain Operations Point Operations Verification What is Verification? Getting Ready to Verify How to Verify MasterCAM is a software suite of Computer Aided Machining (CAM) applications developed by CNC Software, Inc. CAM applications use input geometry alongside machine+tool+stock definitions and user- specified parameters to generate a set of curves called tool paths. These paths are translated into machine-readable instructions through a process called posting. The output file (often using the .nc file extension) contains a list of coordinates that the machine must follow in order to excavate the desired form from the stock material. The most common language for this instruction set is G-code. Like much professional software, MasterCAM is complex and bulky, overloaded with seldom used features, and sports an un-intuitive user interface. Additionally, skillful CNC machining takes time and patience to learn. Students who wish to make use of the CNC capabilities at the GSD are expected to make a good faith effort to learn the basics of the process, but mastery is in no way required. The Fab Lab employs dozens of TA's who are available to offer assistance during scheduled hours both in person and via email. Students are encouraged to build up a working knowledge of the CNC milling procedure incrementally, each time attempting to push their MasterCAM familiarity and proficiency further. In order to set students up for success and reduce a few easily anticipated mistakes, the Fab Lab provides MasterCAM template files. These template files include tool libraries and tool path parameters that are appropriate to the specified stock material. The templates also include helpful suggestions for assigning geometry to each tool path. We highly advise all students to begin their MasterCAM projects by importing their geometry into one of our templates. In addition to the CNC TAs and this online tutorial, the MasterCAM Help menu is itself a valuable resource. You may consider the following as a quick start guide, representing only the minimum information needed for a successful CNC milling outcome. There are several key user interface changes between MasterCAM X9 and 2020. The most noticeable of these is the adoption of a Microsoft Office style "ribbon" in the 2017 version and forward. For those interested in a MasterCAM UI deep dive, these . changes are detailed in this video The following overview covers the basics of MasterCAM 2020 functionality as it pertains to CNC router use at the GSD. Rhino V6 Import MasterCAM 2020 now features the ability to import geometry from Rhino V6 .3dm files.

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Page 1: MasterCAM 2020 Reference - Harvard University

MasterCAM 2020 Reference

Basic NavigationZoom Rotate Pan 

Managing GeometryMerge Geometry Select GeometryMove GeometryDelete GeometryVisibility

Managing LevelsLayers vs. LevelsLevel Manager

Managing PlanesWCS + Tplane + CplanePlane ManagerCreating a Plane

Managing OperationsWhat is a Toolpath?Toolpath ManagerHierarchical OrganizationOperation ComponentsSelecting an OperationOrdering OperationsToolpath VisibilityToolpath Generation

Defining ParametersParameters | UI InconsistenciesParameters | Surface + Chain + Point

Tool SelectionPlanesMachining Heights

Parameters | Surface + Chain 

Stock to LeaveStepoverStepdownCutting MethodMachining Angle

Parameters | Surface Only

Depth Limits Roll ToolTool Containment

Parameters | Chain Only

CompensationLead In / OutMulti Passes Break Through Tabs

Assigning GeometrySurface OperationsChain OperationsPoint Operations

VerificationWhat is Verification?Getting Ready to VerifyHow to Verify

MasterCAM is a software suite of Computer Aided Machining (CAM) applications developed by CNC Software, Inc. CAM applications use input geometry alongside machine+tool+stock definitions and user-specified parameters to generate a set of curves called tool paths. These paths are translated into machine-readable instructions through a process called posting. The output file (often using the .nc file extension) contains a list of coordinates that the machine must follow in order to excavate the desired form from the stock material. The most common language for this instruction set is G-code.

Like much professional software, MasterCAM is complex and bulky, overloaded with seldom used features, and sports an un-intuitive user interface. Additionally, skillful CNC machining takes time and patience to learn. Students who wish to make use of the CNC capabilities at the GSD are expected to make a good faith effort to learn the basics of the process, but mastery is in no way required. The Fab Lab employs dozens of TA's who are available to offer assistance during scheduled hours both in person and via email. Students are encouraged to build up a working knowledge of the CNC milling procedure incrementally, each time attempting to push their MasterCAM familiarity and proficiency further.

In order to set students up for success and reduce a few easily anticipated mistakes, the Fab Lab provides MasterCAM template files. These template files include tool libraries and tool path parameters that are appropriate to the specified stock material. The templates also include helpful suggestions for assigning geometry to each tool path. We highly advise all students to begin their MasterCAM projects by importing their geometry into one of our templates.

In addition to the CNC TAs and this online tutorial, the MasterCAM Help menu is itself a valuable resource. You may consider the following as a quick start guide, representing only the minimum information needed for a successful CNC milling outcome. There are several key user interface changes between MasterCAM X9 and 2020. The most noticeable of these is the adoption of a Microsoft Office style "ribbon" in the 2017 version and forward. For those interested in a MasterCAM UI deep dive, these

.changes are detailed in this video

The following overview covers the basics of MasterCAM 2020 functionality as it pertains to CNC router use at the GSD. 

Rhino V6 Import

MasterCAM 2020 now features the ability to import geometry from Rhino V6 .3dm files.

Page 2: MasterCAM 2020 Reference - Harvard University

MasterCAM SimulatorSimulation PlaybackCollision Checking

Basic Navigation

Zoom 

Scroll with the mouse wheel, or press PGUP and PGDN. Press F1 to initiate Window Zoom, then click and drag the cursor to select a rectangular area on the screen. Zoom to Fit by pressing ALT+F1.

Rotate 

Hold down the center mouse button as you move the cursor, or press ALT + arrow keys.

Pan 

Press ALT as you hold down the center mouse button and move the cursor, or press the arrow keys.

Managing Geometry

Merge Geometry 

Rhino (and other CAD) files are imported by selecting File > Merge. This will insert the geometry from the selected CAD file into current MasterCAM file, keeping the same units and origin from the CAD file. Merges are cumulative, and can be performed at any time. 

After the initial merge, subsequently merged geometry will be added to the active level by default. Users may specify to instead merge additional geometry onto the originally assigned level by ticking the radio button for "Merged File Levels" during the merge process.

Page 3: MasterCAM 2020 Reference - Harvard University

Select Geometry

MasterCAM breaks apart meshes and polysurfaces into their constituent faces and chains into their   segments. The subdivided constituentgeometry may be selected piecemeal, or en masse via window selection. Selected geometry turns yellow. Geometry continues to be added to the selection without holding down shift or another key deselect. To   geometry, click on it a second time, or press the ESC key to deselect all. The Level Manager can be used to simplify geometry selection by altering the visibility of various levels. 

Page 4: MasterCAM 2020 Reference - Harvard University

Move Geometry

Choose "Transform" from the ribbon. Selected geometry can now be manipulated by choosing the desired transformation (Translate, Rotate, Mirror, etc) from the ribbon. Change the Method from Copy to Move, next input the increment of the transformation (units XYZ, degrees, etc). Geometry that undergoes a transformation within MasterCAM will retain its operation assignments, however, the operations will become dirty and require regeneration.

Page 5: MasterCAM 2020 Reference - Harvard University

Delete Geometry

Press F5 or DEL to delete selected geometry. If the geometry is included in a toolpath, a dialog box will appear to warn you. To continue, choose “Delete all selected entities”. The selected geometry will then be deleted. Previously associated toolpaths will remain, but will no longer work (they are now "dirty"). 

Visibility

Default MasterCAM view is . Shaded Toggle Wireframe by pressing ALT+S, or choosing View from the ribbon and selecting Wireframe. This will Toggle display by pressing CTRL+T, or choosing View from the ribbon and selecting Translucency. This change selectable geometry.  Ghosted

will not change selectable geometry. Toggle unselected geometry (show/hide) by pressing ALT+E.

Snapping

MasterCAM has limited object snapping capabilities as compared with Rhino. This can make complex geometry transformations a chore within MasterCAM. Often it may be easier to delete the MasterCAM geometry, perform the desired transformation within Rhino, and merge the relocated geometry back into MasterCAM. This will require the reassignment of any toolpaths that referenced the deleted geometry.

Page 6: MasterCAM 2020 Reference - Harvard University

Managing Levels

Layers vs. Levels

MasterCAM geometry can be organized into Levels, which are analogous to Rhino Layers. As with Rhino Layers, Levels may be shown or hidden selectively to allow for easier geometry selection or to decrease visual clutter. Rhino layers will be imported as levels, and the associated geometry will maintain its layer-assigned color. MasterCAM does not use a nested hierarchy for levels, so this organization will be lost when importing from Rhino.

Level Manager

The Level Manager is accessed from Managers pane (defaults to left side of window). Select the Levels tab at the bottom of the pane to see the currently defined levels. The Active Level is designated by a green check mark, and cannot be hidden by default. Click next to a different level's number to make it active instead. Show or Hide levels by clicking the X in the Visible column. Use levels for easy geometry selection by right clicking the desired level's row and choosing Select All Entities.

Layer Colors

MasterCAM uses Yellow to indicate geometry selections, and will not display edges for geometry whose Rhino Layer color is Black. So, it is best to avoid using black or yellow for all Rhino layers with geometry prior to merging.

Page 7: MasterCAM 2020 Reference - Harvard University

Managing Planes

WCS + Tplane + Cplane

Each operation generates toolpaths according to the Work Coordinate System ( ), Tool Plane ( ), and Construction Plane ( ) WCS Tplane Cplanethat is specified in its parameters. The currently specified planes are also visible in the Toolpath Manager alongside the operation name. The WCS, Tplane, and Cplane should always match for any given operation.

Plane Manager

The Plane Manager allows users to view, create, modify, and delete planes. These planes are referenced by operations in order to draw toolpaths. 

Page 8: MasterCAM 2020 Reference - Harvard University

Creating a Plane

In some cases, the default planes may not be appropriate for an operation. For example, the flipped side of a two-sided milling job cannot reference the default Top plane, so a new plane must be created. The most straightforward method is to duplicate an existing plane whose axes are in the preferred orientation, and then enter new origin coordinates for the duplicate plane. 

Page 9: MasterCAM 2020 Reference - Harvard University

Managing Operations

What is a Toolpath?

A toolpath is the path through space that the tip of a cutting tool follows on its way to producing the desired geometry of the workpiece. In MasterCAM, toolpaths are represented by blue and yellow lines that are drawn across the surface of your imported geometry. Each toolpath is the result of an operation.

Toolpath Manager

Operations can be created, modified, and deleted in the toolpath manager. It is found within the managers pane, which defaults to the left of the modeling window. 

Hierarchical Organization

The toolpath manager displays information in a file tree format, with the Machine Group as the top-level directory. The machine group contains 

properties  (contains the machine definition and stock setup) followed by a toolpath group (contains some number of operations). The order of the operations is critical, as MasterCAM will output each in sequence to the simulator, or when the file is posted for running on the mill. 

Operation Components

Within the toolpath manager, operations are displayed as a numbered yellow folder icon with four nested components: Parameters, Tool, Geometry, Toolpath. 

Page 10: MasterCAM 2020 Reference - Harvard University

Operation 

This shows the operation number, the type of operation, the selected Work Coordinate System (WCS), Tool Plane (Tplane), and a few helpful comments about usage. 

Parameters

Click here to open the parameters window for the specific operation. The parameters window layout differs depending on whether the operation surface or chain (curve) based.

Tool

Displays currently selected tool for the parent operation. Click here to open the tool window, where aspects of the currently selected tool may be redefined. 

Geometry

Displays quantity of geometry currently assigned for different functions of the parent operation. Click here to open the geometry window, where geometry may be assigned.

Toolpath

Displays current status and size of toolpath for parent operation.

Selecting an Operation

Click on the operation folder icon of the desired operation. Once selected, the operation folder icon will be open and show a green check mark.

Page 11: MasterCAM 2020 Reference - Harvard University

Ordering Operations

Selected Operations may rearranged by clicking and holding on the Operation folder icon, then dragging the Operation to a new position within

the ordered Toolpath Group. However, it is frequently more precise to manipulate the operation order by using the Insertion Arrow and its

controls  . The Insertion Arrow exists as a placeholder within the Toolpath Group to allow for the creation of new

Operations. The Insertion Arrow can be repositioned by using the  Up and Down controls. Once the Insertion Arrow is in the correct position, you may right click on it to create a new Operation, or paste an Operation that was previously copied. 

Page 12: MasterCAM 2020 Reference - Harvard University

Toolpath Visibility

MasterCAM defaults to drawing all toolpaths simultaneously in the modeling window. The toolpath for the selected operation can be

toggled by clicking  . Often it is most practical to only show the selected operation's toolpath while automatically hiding all unselected

operation's toolpaths. Toggle this setting by clicking  .

Toolpath Generation

In most cases, MasterCAM will not automatically generate the toolpath for a selected operation after its parameters and geometry have been assigned. If the operation lacks assigned geometry, or has had any changes made to the geometry assignment or parameter definitions, then

the operation is considered "dirty" and the   toolpath icon will instead display  . Dirty operations must be regenerated before verification

or posting. Regenerate the selected operation by clicking  , or regenerate all dirty operations by clicking  .

Page 13: MasterCAM 2020 Reference - Harvard University

Defining Parameters

Parameters | UI Inconsistencies

MasterCAM displays parameters for surface-based operations with a tabbed interface, while chain-based and point-based operations use a file-tree interface. Some of the parameters are common across operation type, while others are unique or have multiple names depending on location within the interface.

This disambiguation organizes parameters by the types of operations for which they are applicable.

Page 14: MasterCAM 2020 Reference - Harvard University

Parameters | Surface + Chain + Point

Tool Selection

A tool is a piece of cutting hardware that does the actual work of excavating the desired geometry from the stock material. Each tool is a cylindrical piece of metal that has been shaped to perform a particular job. Some tools may be shaped to cut specific materials or give a special finish, while others may be more general purpose. A tool must be assigned to every operation, and each operation may have only one tool. The material-specific template files provided by the GSD FabLab include our default tool libraries. An operation will pre-populate some parameters from the tool library automatically based on the tool selection. The feed rate, plunge, and spindle speed will all be drawn from the library, though these can be overridden by entering a value in the operation parameters. 

The effects of many parameters depend directly on the tool selection, so it is important to update all aspects of an operation's parameters (stepover, stepdown, etc) if the tool selection changes. The tool selection interface resides in a different location of the parameters window, depending on whether the selected operation is surface or chain based. 

Surface-based operations require tool selection on the Parameters > Toolpath Parameters (first tab) page. 

Chain-based and point-based operations require tool selection on the Parameters > Tool subheading.

Page 15: MasterCAM 2020 Reference - Harvard University
Page 16: MasterCAM 2020 Reference - Harvard University

Planes

Each operation generates toolpaths according to the Work Coordinate System ( ), Tool Plane ( ), and Construction Plane ( ) WCS Tplane Cplanethat is specified in its parameters. The currently specified planes are also visible in the Toolpath Manager alongside the operation name. The WCS, Tplane, and Cplane should always match for any given operation.

In most cases, the TOP plane should be specified for all operations. The only exception is when machining the underside of a two-sided job (flip milling). In this circumstance, select FLIP as work coordinate system, tool plane, and construction plane. FLIP plane must first be defined in the Plane Manager.

Surface-based operations allow specifying planes on the Parameters > Toolpath Parameters (first tab) page. 

Chain-based and point-based operations allow specifying planes on the Parameters > Planes subheading.

Page 17: MasterCAM 2020 Reference - Harvard University
Page 18: MasterCAM 2020 Reference - Harvard University

Machining Heights

During an operation, not every movement of the tool will make contact with the stock material. In between cutting movements (toolpaths shown in blue), the machine must make rapid movements (toolpaths shown in yellow) to reposition. In order to prevent accidental damage to the machined part, MasterCAM requires each operation to specify a safe area where rapid movements will not inadvertently cut through the stock.

Each height value must be specified as (the input height value is offset from the WCS origin), (the input height value is Absolute Incrementaloffset from the selected operation's assigned geometry), or (the input height value is offset from the defined stock) . Typically, an Associative operation will define a Clearance, Retract, Feed Plane, Top of Stock, and Depth, though some operations may not require every value. 

Surface-based operations accept machining height values on the Parameters > Surface Parameters (second tab) page. 

Chain-based and point-based operations accept machining height values on the Parameters > Linking Parameters subheading.

Clearance

Specifies the height of the rapid movements at the start and finish of job. Recommended to be stock height + 0.5" absolute.

Retract

Specifies the height that all other non-cutting rapid movements throughout the duration of posted operations. Recommended to be stock height + 0.25" absolute.

Feed Plane

Specifies the height at which the machine begins cutting movements. Recommended to be stock height + 0.1" absolute.

Top of Stock

Page 19: MasterCAM 2020 Reference - Harvard University

Input the thickness of the stock as entered into the  properties. 

Depth

Specifies the height at which chains will be cut. If the imported geometry has been arranged in space at the desired cutting height, the depth should be set to 0.0" incremental. 

Page 20: MasterCAM 2020 Reference - Harvard University

Parameters | Surface + Chain 

Stock to Leave

MasterCAM allows the user to define an offset, either negative or positive, to be applied between the tool tip and control geometry during an operation. This is useful in a number of situations, but is most commonly used to allow the roughing operation to leave behind a bit of excess material for the finishing operations to clean up afterwards. 

Surface-based operations accept stock-to-leave values for Drive and Check surfaces separately. Users can specify on the Parameters >  Surface Parameters (second tab) page.

Chain-based operations accept stock-to-leave values for floors and walls separately. Users can specify on the Parameters > Cut  Parameters subheading.

Page 21: MasterCAM 2020 Reference - Harvard University
Page 22: MasterCAM 2020 Reference - Harvard University

Stepover

Operations that clear a broad area typically do so by drawing a trace across the input geometry that the tool will follow, then offsetting some distance to draw an adjacent trace, and so on. This offset distance is called the stepover, and has a direct relationship to the finish quality and machining time of a part. In general, a decrease in stepover corresponds with a decrease in roughness and an increase in machining time. The maximum stepover for an operation should not exceed the diameter of the tool. Stepover must necessarily decrease from this maximum as the density of the stock material, and thus stress on the tool, increases.

Surface-based operations that clear material laterally (Parallel, Shallow, Scallop) require a maximum stepover value to be defined. Users can specify on the Parameters > (third tab) page. operation specific

Chain-based operations that clear material laterally (Pocket, Contour 2D/3D multi passes) require a maximum stepover (aka "spacing") value to be defined. The location for inputting this value varies by operation.

Reference Pages

Selecting a Stepover

Page 23: MasterCAM 2020 Reference - Harvard University
Page 24: MasterCAM 2020 Reference - Harvard University

Stepdown

When the depth of cut required to clear stock material from the control geometry is greater than the flute length of the tool, it is necessary to cut down in layered depth intervals. The height of each depth interval is called the stepdown. In general, an increase in stepdown corresponds with

he maximum stepdown for an operation should not exceed the flute length of the tool used. Stepdown a decrease in machining time, though, tmust necessarily decrease from this maximum as the density of the stock material, and thus stress on the tool, increases.

Surface-based operations that clear material vertically (Parallel, Contour) require a maximum stepdown value to be defined. Users can specify on the Parameters > (third tab) page.operation specific

Chain-based operations that clear material vertically (Pocket, Contour 2D/3D) require a maximum stepdown value to be defined. Users can specify on the Parameters > Cut Parameters > Depth Cuts subheading.

Page 25: MasterCAM 2020 Reference - Harvard University
Page 26: MasterCAM 2020 Reference - Harvard University

Cutting Method

Surface-based operations that clear material laterally (Parallel, Shallow, Scallop). Users can specify on the Parameters > operation specific(third tab) page.

Chain-based operations that clear material laterally (Pocket). Users can specify on the Parameters > Cut Parameters > Roughing subheading.

This method determines the way in which the toolpaths are drawn across the input geometry. 

One Way 

The tool will engage the stock in one orientation in a parallel manner, either  climb-cutting or conventional-cutting. The machine will retract after each cut and rapid to the start of the next cut. 

Zigzag

The tool will engage the stock in two orientations in a parallel manner, both climb-cutting and conventional-cutting within the same toolpath. The machine will retract at the end of each stepdown increment and rapid to the start point.

3DCollapse

The tool will engage the stock in one orientation in a concentric manner, either climb-cutting or conventional-cutting. The machine will retract as each collapse zone is completed, then rapid to the next zone.

Page 27: MasterCAM 2020 Reference - Harvard University
Page 28: MasterCAM 2020 Reference - Harvard University

Machining Angle

Surface-based operations that clear material laterally (Parallel, Shallow). Users can specify on the Parameters > (third operation specifictab) page.

Chain-based operations that clear material laterally (Pocket). Users can specify on the Parameters > Cut Parameters > Roughing subheading. 

Only applies to One Way or Zigzag cutting methods.

Machining angles allow parallel toolpaths to be rotated relative to the WCS. The default angle of 0 produces toolpath traces with the long direction parallel to the X axis. Increasing the angle rotates the long axis counterclockwise, such that an angle of 90 produces toolpath traces whose long axis is parallel to the Y axis.

Page 29: MasterCAM 2020 Reference - Harvard University
Page 30: MasterCAM 2020 Reference - Harvard University

Parameters | Surface Only

Depth Limits 

aka "Cut Depths" on Surface Rough Parallel and Surface Finish Contour operations. Users can specify on the Parameters > operation (third tab) page.specific

Constrains cutting moves between minimum and maximum Z heights.

Page 31: MasterCAM 2020 Reference - Harvard University

Roll Tool

Users can specify on the Parameters > (third tab) > Advanced Settings.operation specific

Determines whether any portion of the tool is allowed to cut outside the perimeter of the drive surfaces. Defaults is to decide automatically.

Page 32: MasterCAM 2020 Reference - Harvard University

Tool Containment

Users can specify on the Parameters > Surface Parameters (second tab) page.

Applicable when containment curve(s) is(are) assigned. Determines how tightly the toolpath is constrained. 

Inside

The tool tip is kept inside the containment curve by an offset of 50% tool diameter

Center

The tool tip follows the containment curve on-center

Outside

The tool tip is allowed outside the containment curve by an offset of 50% tool diameter

Page 33: MasterCAM 2020 Reference - Harvard University

Parameters | Chain Only

Compensation

MasterCAM applies Cutter Compensation when drawing toolpaths based on the input chains. By default, MasterCAM will offset to one side or

the other from the input chains by the distance equal to the operation's selected tool's radius. By default, MasterCAM compensates to the  L

eft or  Right depending on what part of the chain is clicked.

To ensure that all selected chains offset to a particular side, choose Options in the Wireframe Chaining window, then uncheck "Use cursor position" from the Closed Chains field. The Change Side and Reverse functions of the Chain Manager provide additional control over compensation direction.

If the input chains are intended to be centerlines for the operation, Compensation must be turned  OFF

Users can specify on the Parameters > Cut Parameters subheading.

Page 34: MasterCAM 2020 Reference - Harvard University

Lead In / Out

Users can specify on the Parameters > Cut Parameters > Lead In / Out subheading.

Commonly used to gradually feed the cutting tool into and out of the stock using line and/or arc elements. This reduces stress on the tool, decreasing overall wear and the chance of breakage.

Page 35: MasterCAM 2020 Reference - Harvard University

Multi Passes 

Users can specify on the Parameters > Cut Parameters > Multi Passes subheading.

Creates multiple adjacent toolpath traces from a single input chain. The input chain is offset a specified number of times across a specified distance at the same Z height.

Page 36: MasterCAM 2020 Reference - Harvard University

Break Through 

Users can specify on the Parameters > Cut Parameters > Break Through subheading.

An additional negative Z height offset to push the tool through the bottom of the stock.

(Avoid use for best practice. Overlaps with stock-to-leave and linking parameters.)

Page 37: MasterCAM 2020 Reference - Harvard University

Tabs

Users can specify on the Parameters > Cut Parameters > Tabs subheading.

Prevents a part from being fully separated from its stock material by leaving behind periodic bridges along the base of a contour cut out. Useful for preserving small parts when using vacuum hold-down, and necessary for all parts when using mechanical hold-down.

Tabs can be generated automatically or manually. When generated manually, users must place the tabs by clicking on portions of the input chain. Tab thickness, width, and ramp angle may also be specified.

Tabs can be moved or deleted individually after creation.

Page 38: MasterCAM 2020 Reference - Harvard University
Page 39: MasterCAM 2020 Reference - Harvard University
Page 40: MasterCAM 2020 Reference - Harvard University

Assigning Geometry

Surface Operations

Most surface-based operations request the assignment of four types of control geometry: Drive, Check, Containment, and Approximate Starting Point. Of these, only Drive is required for toolpath generation, however, it is usually necessary to define additional types of control geometry in

order to avoid accidental collisions. Click the  geometry component of the selected operation to open the Toolpath/Surface Selection

window. In this window, click   to make your geometry selection or click   to clear the previous geometry selection. MasterCAM displays selected geometry in yellow. Press ENTER to save your selection, or ESC to cancel it.

Drive

These are the surfaces that will be milled during the selected operation.

Check

These are the surfaces that will be avoided during the selected operation.

Containment

These are closed chains that specify which portions of the geometry are to be milled or avoided, depending on whether the geometry falls within the chain's perimeter when viewed perpendicular to the Tplane.

Page 41: MasterCAM 2020 Reference - Harvard University

Approximate Starting Point

This point specifies where MasterCAM will begin drawing the toolpath for the selected operation. It is useful when sorting geometry by proximity to reduce machining time by optimizing travel path.

Chain Operations

Chain-based operations use chains as the primary control geometry, but also accept a Start Point for sorting. Some operations (such as Pocket) will only accept closed chains, while other operations will accept both closed and open chains.

Often it is necessary to check each chain once selected to ensure the compensation is in the correct direction. MasterCAM displays this information via four arrows overlayed onto the selected chain. Green arrows indicate the entry point of the chain, while red arrows mark the exit point. The larger green or red arrow indicate the direction of travel that the tool will follow along the chain. The smaller green or red arrow indicates the direction of compensation to be applied to the selected chain. 

Click the  geometry component of the selected operation to open the Chain Manager. This window uses its own  Insertion Arrow and

. Right-click within the white portion of the Chain Manager window to bring up the contextual menu. The key controls functions present on this menu are: Add, Change Side, Sort Options, Delete, Reverse, and Edit Tabs. 

Choosing the Add function brings up the Wireframe Chaining window. There are several options in the Selection Method field that can provide extra control over chain selection. By default, the selection method is set to Chain, but Partial, Window, Polygon, and Single methods may be occasionally useful. 

Add

Enables the selection of chains. Selected chains turn yellow. MasterCAM may break chains into constituent segments even when the original imported Rhino curves were joined.

Page 42: MasterCAM 2020 Reference - Harvard University

Change Side

Changes compensation side for all chains assigned to selected operation.

Sort Options

Sort chains according to proximity to each other and/or an input Start Point in order to reduce machining time by optimizing travel path.

Delete

Deleted selected chain. Can also press DELETE while Chain Manager window has focus.

Reverse

Changes compensation side for only selected chain.

Edit Tabs

Move or Delete previously generated tabs.

Chain

Manually select a chain segment, and MasterCAM will attempt to automatically select the entire chain. Segments must share vertices, be continuous, and have no self-intersections.

Partial

Manually select several continuous chain segments, and MasterCAM will process them as one chain.

Window

Click and drag in the model space to select chain segments within a rectangular box.

Polygon

Click to draw a selection polygon (similar to Rhino Lasso command) in the model space.

Single

Manually select several chain segments (continuous or not), and MasterCAM will process them as individual chains. Each segment will have its own lead in / lead out.

Page 43: MasterCAM 2020 Reference - Harvard University

Point Operations

Verification

What is Verification?

Verification (aka Simulation) is the process of playing out the generated toolpaths in a virtual environment in order to check for errors and omissions. Successful verification (accurate stock and tool definitions, no collisions found) is a necessary pre-requisite to performing any real CNC machining at the GSD. Student submitted jobs will not be approved or scheduled until successful verification is demonstrated. 

Getting Ready to Verify

During Verification, each selected operation will be processed in the order it is placed within the  toolpath group; unselected operati

ons will not be processed. Dirty operations cannot be verified, and must be regenerated before verification can commence. 

How to Verify

Select all operations that have been configured and will be used. Next, click   verify selected operations in the Toolpath Manager to open the Mastercam Simulator window.

Page 44: MasterCAM 2020 Reference - Harvard University

MasterCAM Simulator

The MasterCAM Simulator creates a virtual environment for testing the validity of selected operations. The generated toolpaths are run in order using the current machine, tool, and stock definitions. It is vital to use accurate tool and stock definitions (representative of the configuration that is loaded onto the CNC machine) for the verification process to produce meaningful results. In addition to visually confirming that the verified geometry matches the designer's intent, MasterCAM Simulator also reports collisions that would result from running the selected operations on the CNC machine with current definitions and parameters. 

The MasterCAM Simulator window includes the simulation environment, the ribbon menu, and the information pane. 

Simulation Playback

MasterCAM Simulator displays simulation progress along a timeline at the bottom of the simulation environment. The timeline is transparent, but becomes opaque on mouse hover. Toggle the simulation playback by pressing R or clicking the play/pause button. Users can scrub backward and forward along the timeline by clicking and dragging the red slider, or incrementally by pressing B (backward) and S (forward). Users may skip to the previous or next operation by pressing P (previous) and N (next). Users may skip to the start or end of the job by pressing HOME (start) or SPACE (end). 

Collision Checking

Collisions occur when any portion of the CNC machine or tool that is non-cutting comes into contact with the stock material. Ensure that collision checking is activated before starting the simulation. First, choose Home > Stop Conditions from the MasterCAM Simulator ribbon menu, and then check Collision. Next, choose Home > Tool Components from the MasterCAM Simulator ribbon menu, and then check all items in the Milling field (Holder, Shank, Shoulder, Flute Length). Finally, choose File > Options and then enable all Collision Checking options for Stock and Mill Tool (Mill tool holder, Mill tool shank, Mill tool shoulder, Mill tool cutting length).

During simulation playback, areas of the stock involved in a collision will be colored dark red. The type of collision can be identified in the Collision Report.

Page 45: MasterCAM 2020 Reference - Harvard University