Mastercam Handbook Volume 2 for Mastercam X6 Copyright © 1984 - 2012 In-House Solutions Inc. - All rights reserved. Software: Mastercam X6 Mill Level 3 & Solids Authors: In House Solutions ISBN: 978-1-926955-46-9 Revision Date: February 8, 2012 Notice In-House Solutions Inc. reserves the right to make improvements to this manual at any time and without notice. Disclaimer of All Warranties and Liability In-House Solutions Inc. makes no warranties, either express or implied, with respect to this manual or with respect to the software described in this manual, its quality, performance, merchantability, or fitness for any particular purpose. This In-House Solutions Inc. manual is sold or licensed "as is." The entire risk as to its quality and performance is with the buyer. Should the manual prove defective following its purchase, the buyer (and not In-House Solutions Inc., its distributor, or its retailer) assumes the entire cost of all necessary servicing, repair, of correction and any incidental or consequential damages. In no event will In-House Solutions Inc. be liable for direct, indirect, or consequential damages resulting from any defects in the manual, even if InHouse Solutions Inc. has been advised of the possibility of such damages. Some jurisdictions do not allow the exclusion or limitation of implied warranties or liability for incidental or consequential damages, so the above limitation or exclusion may not apply to you. Copyrights This manual is protected under International copyright laws. All rights are reserved. This document may not, in whole or part, be copied, photocopied, reproduced, translated or reduced to any electronic medium or machine readable form without prior consent, in writing, from In-House Solutions Inc. Trademarks Mastercam is a registered trademark of CNC Software, Inc. Microsoft, the Microsoft logo, MS, and MS-DOS are registered trademarks of Microsoft Corporation; Windows2000, Windows XP, Windows 7 are registered trademarks of Microsoft Corporation.
This document complies with Mastercam X6 as of January 2012. Requires Mastercam Mill Level 3 and Solids.
Contents Introduction
Chapter 1
3D Workspace
Chapter 2
Splines
Chapter 3
Surface Modeling
Chapter 4
Surface Rough Machining
Chapter 5
Surface Finish Machining
Chapter 6
Surface High Speed Toolpaths
Chapter 7
Mold Project
Chapter 8
Prototype Project
App. A
CNC Programming Planning Sheet
App. B
Drill Chart
Introduction The Handbook can be used as the primary resource for a Mastercam class, as a self-study guide, or a shop reference. Mastercam help functions and information on the student CD supplement the material in this book. A unique feature of this book is the comprehensive, top-down approach it takes to learning. Concepts and essential knowledge are included along with practical applications. This approach means you not only learn how to use Mastercam, but why things work as they do. By understanding exactly what you are doing and why each step of the way, you learn to recognize the best approach to problems. Not only will you be better prepared to work effectively, you will gain a solid foundation of knowledge that will help you continue to learn and adapt as technology changes. Specific recommendations about how to best use Mastercam are included. There are often many ways to accomplish any task. However, you will learn faster and understand the overall picture of what you are doing if you first master fundamentals and standard practices. In any case where information in this book conflicts with your machine manuals or the methods used at your company or school, ignore the suggestions in this book and use the information in the manuals and established procedures at your facility. Never operate a CNC Machine without having read and understood the operator and programmer manual, and having received safety and operator training by a qualified person on that machine.
Contents
This book is divided into ten chapters. Each covers a specific knowledge area. Following is a breakdown of the chapters and what you will find in each: Chapter 1: 3D Workspace explains the Mastercam 3D work environment. Chapter 2: Splines shows how to create and machine splines. Spline modeling and machining concepts are an essential foundation for surface modeling and machining. Chapter 3: Surface Modeling shows how to create and modify all types of surfaces in Mastercam. Chapter 4: Surface Rough Machining shows how to remove excess material from a surface or solid model in preparation for finish machining. Chapter 5: Surface Finish Machining shows how to finish machine surface and solid models. Chapter 6: Surface High Speed Toolpaths introduces concepts and principles of high speed machining and how to use Mastercam’s advanced surface high speed rough and finish toolpaths. Chapter 7: Mold Project introduces basic mold concepts and terminology. A simple two piece working plastic injection mold is made starting with prints. Chapter 8: Prototype Project is an assignment that starts with a complex CAD surface model. The model is prepared for machining and then rough and finished machined. App. A: NC Program Planning Sheet is a template used to document the machining process. App. B: Drill Chart
Icons are used to alert, inform, and enhance your learning experience. The following icons are found in the margins of the book:
Remember reminds you of important information that will help you work safely and productively.
Tips are suggestions from experienced CAD/CAM users that will guide your learning and use of Mastercam.
Step by Step are detailed instructions on how to use a specific function or perform a task.
On the CD alerts you that a file exists on the CD included with this manual that may be necessary for accomplishing a task.
Try It assigns a task you should be able to successfully complete before proceeding further.
Warning is used to emphasize situations that can cause damage to machines, property, bodily injury or death. Machining can be dangerous. Take these warnings seriously and do not proceed unless you are certain your methods and setup are completely safe.
In Depth are notes of interest that deepen your understanding and knowledge of a topic.
Power User denotes tips that are likely only applicable to the highest level users of Mastercam.
Icons
Conventions
Key words and Mastercam menu items are shown in bold the first time they are used. Columns on the outside edges of each page and note pages at the end of each chapter provide ample space for taking notes. Useful tips, recommended settings, best practices, and detailed instruction on the most important features are included when possible. Extra credit exercises are included on the student CD in PDF format. These will help build your skill to a higher level.
The following terms are used throughout this book. Left Click means to click once on the left mouse button. Click means the same as left click. Right Click means to click once on the right mouse button. Scroll means to roll the mouse scroll wheel, or move the scroll index in a list. Options are Mastercam functions selected from the main menu. Enter means to select the
key on your computer keyboard. Press means to press on a keyboard key. Choose means to select a menu option or button. Open/Close means to open or close a dialog or information box. Dialog Box is a window that opens to allow input of information and setting of defaults. Drop Down/Fly Out Menus are menus that expand down, left, right, or up, to reveal more menu lists. A Function is the same as a menu option or command. Help means the Mastercam help files loaded with your software.
Common Terms
Surface Modeling
3
Surface Modeling
This chapter shows how to model parts using surfaces. Upon completion of this chapter, you should be able to do the following:
Objectives
Understand the difference between wireframe and surface geometry. Understand common surface definitions. Identify and create basic surfaces including Ruled, Lofted, Revolved, and Draft. Recognize and create advanced surfaces including Swept, Net, Fence, Trim, Fillet, and Offset surfaces. Create surfaces that blend plane, curve, or other surfaces. Recognize which surface type(s) are suitable given the wireframe geometry and part feature requirements. Trim surfaces to a curve, plane, or other surfaces. Extend split and un-trim surfaces. Remove trim surface boundaries and fill holes in surfaces.
Wireframe geometry consists of lines, arcs, and splines. These entities describe only the edges of the part. They contain no information about what lies on the faces of the part between the edges.
Introduction
To illustrate, use Analyze Dynamic and select the edge geometry of any 3D wireframe part. As you drag the mouse along the wireframe edges, the system displays coordinates. Clicking on the faces of the part fails to select the face and provides no geometry information. While wireframe geometry includes enough information to model and machine 2D parts, more complex ones, especially those with complex and organic shapes, require more. These parts need information about every point that lies on every face of the part. Surfaces and Solids include face information required to model and machine these complex 3D shapes.
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CAD Geometry Types
There are three types of geometry used by CAD/CAM software:
Wireframe Surfaces Solids
Geometry Type Wireframe
Surfaces
Solids
3-2
Description Wireframe geometry consists of curves (lines, arcs, points and splines) and points. Wireframe geometry includes information only about the edges of a part. Wireframe models cannot be shaded. Wireframe geometry is adequate to model and machine most prismatic or “2-1/2D” parts –where all contours exist in flat planes. A surface can be thought of as an infinitely thin shell stretched over a wireframe. Surfaces can have a 3D shape with length and breadth, but they have no thickness. Surface geometry includes information about the faces and edges of a part. There are many types of surfaces; each suited to model a specific type of shape. Surfaces are used to model complex, freeform (organic) shapes common in the automotive, aircraft, mold, and consumer goods industries. Solids contain information about the edges, faces, and interior of the part. Most mechanical parts are now designed using Solid Modeling software, like Mastercam Solids®, SolidWorks®, SolidEdge®, ProEngineer®, and others. Solids are able to model many parts, but some highly sculpted shapes, like car bodies, are best modeled using surfaces. All Solids start with profiles of wireframe geometry.
Mastercam X6
Surface Modeling
Surfaces begin with wireframe geometry: lines, arcs, splines and points. These entities form profiles, or curves, referred to as Drive Curves. Depending on the surface type and shape, one, two or more drive curves may be required to define a surface. These curves are revolved, swept, or otherwise used to create the surface.
Surface Terms
With some surface types, drive curves are referred to as running in the Along or Across direction, depending on whether they run along or across the predominate shape of the part. UV curves are curves that run along and across the face of the surface at regular intervals. UV lines are not geometric entities. They cannot be selected for any purpose. They are simply used to help visualize the shape of the surface when shading is turned off. The density, or number of UV lines per surface, can be set for each surface before it is created. A surface normal is a vector that points away from the surface at a 90degree angle at any particular point on the surface. The direction of the normal can be, and often is, different for every position on the surface. The surface normal is used for certain surface creation, manipulation, and machining operations. All surfaces can be thought of as having two sides; one that the normal points away from and the opposite side. When shading is not active, the normal side is colored. The opposite side is dull gray. The surface normal can be displayed using Analyze Dynamic. The normal can be flipped from one side to the other using the Edit, Set Normal or Change Normal functions.
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The following illustration shows all common surface terminology.
Surface Shaded Drive Curves UV Curves Surface Normal
Legend
Surface Terms
Item Drive Curves UV Curves
Surface Normal Shading
Translucent
3-4
Definition Curves used to define the surface. Used to help visualize the shape of the surface when shading is not active. UV lines are not selectable geometry, but are for display only. A vector that points away from the surface at a 90 degree angle all around at any particular point on the surface. Shading provides a photorealistic rendering of surface and solid models. It can be turned on/off using Alt-S or the shading toolbar. A shading mode that allows you to partially see through the shaded object. Mastercam X6
Surface Modeling
Many different types of surfaces have been developed. Each uses a different mathematical model to describe a certain type of shape. Surfaces may have different wireframe geometry requirements and offer relative strengths and weaknesses compared to other surface types. While some shapes can be modeled using different types of surfaces, often only one is best suited for that shape.
Surface Types
Recognizing which surface to use in a given situation, and how to build that surface, is a skill. This skill is developed by first understanding each surface type, its potential applications, and its relative strengths and weaknesses. It takes practice to develop an eye for recognizing which surfaces to use and to acquire the skills needed to create them. Surfaces supported by Mastercam are shown in the menus below.
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Ruled Surface
Ruled surfaces are created by linearly blending between two or more contours. Think of this as making the shape by creating evenly spaced lines between the two curves. These curves can be made up of lines, arcs, splines or points. Most ruled surfaces use two curves to define the surface. Notice that the UV curves along the ruled surface are linear.
Surface Shaded Drive Curves UV Curves
Legend
Contour-1
Contour-2
Ruled Surface
Ruled-1.MCX
Consider using a Ruled surface to model a shape that could be formed by drawing equally spaced lines between two or more curves.
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Mastercam X6
Surface Modeling
Follow the steps below to create a simple ruled surface. This example uses the file, Ruled - 1.MCX, which is included on your student CD,
Ruled Surface
Step 1: Select the Create Ruled / Lofted Surface function from the main menu or the Surfaces toolbar.
Created Ruled / Lofted Surface
Step 2: Select the Ruled setting on the Create Ruled / Lofted Surface ribbon bar.
Ruled Lofted
Step 3: Chain Curve 1 and then Curve 2. Be sure to pick the curves from the same side so they chain in the same direction or the surface will be twisted. Close the Chain Manager and then select OK or Apply on the Ruled/Lofted surface toolbar. Twisted Surface Contour 1
Contour 2
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Rule To Point
One of the curves for a ruled surface can be a point entity. This blends the curve as shown in the example below. Simply select the Point option in the Chaining dialog box and pick the point.
Curve
Point
Rule Curve to Point
RuleToPoint.MCX
Rules and Suggestions for Ruled Surfaces:
3-8
Always select both drive curves in the same direction. If you select in opposite directions, the surface will be twisted. Turn shading on to make it easier to see any errors in the surface. Very complex drive curves can cause problems creating the surface. Consider using partial chains to model the shape with two or more ruled surfaces instead of one. In other words, create the shape using several simple surfaces rather than one complex surface. Sharp corners in drive curves will sometimes be ignored. Mastercam will display a warning in this case. Consider creating the shape using multiple ruled surfaces or using the Chaining Option, Sync mode. Sometimes putting a small fillet radius (.001-.005 inches) on sharp corners will cause the surface to transition smoothly along the curve. Sync mode is covered under Draft Surfaces in this chapter.
Mastercam X6
Surface Modeling
A Lofted surface is similar to a Ruled surface except blending between the curves uses splines instead of lines. This creates a surface that flows smoothly between multiple curves.
Lofted Surface
Lofted surfaces are used extensively in the boat building and aircraft industry. Examples of parts that use lofted surfaces include wings, propellers, turbine blades, and boat hulls. Lofted surfaces have three or more drive curves, called Lofting Sections or Lofting Stations, which are usually parallel to each other. A lofted surface with only two drive curves would be the same as a ruled surface, since there would be only two node points on the blending splines, making them linear.
Surface Shaded Lofting Sections UV Curves (Spline Blending)
Legend
LoftWing.MCX
Lofted Surface Consider using a Lofted surface when the drive curves are cross sections of the resulting shape, and the shape can be formed by blending splines equally between these sections.
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Rules and Suggestions for Lofted Surfaces:
Revolved Surface
The same tips for ruled surface drive curves apply for lofted Surfaces. Cross sections should exist on the same Cplane. If needed, use the Xform Project, Plane function to force all entities in a cross section to the same plane. Chain all drive curves in the same direction or the surface will twist. For problems with spline drive curves, check for excess node points and consider removing excess nodes. If the problem persists, use Analyze Dynamic to check for nodes that incorrectly reverse the spline abruptly. Re-create the spline if all else fails.
A revolved surface is created by spinning a profile about a line, called the axis of revolution. This line must exist before the revolved surface function is selected. Surface Shaded Profile Axis of Revolution UV Lines Direction Symbol
Legend
RevolveSurf.MCX
Revolved Surface
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Mastercam X6
Surface Modeling
Revolved surfaces are controlled by the ribbon bar shown below. Profile Axis
Flip Start Angle End Angle
Item Profile Axis Flip Start Angle End Angle
Definition The curves to be revolved. The axis of revolution. An existing line that the profile will be spun around. Flip direction of revolution. Degrees of rotation where the surface begins, in relation to the plane that the profile resides in. Degrees of rotation where the surface ends.
Angles are in reference to the construction plane (Cplane) that the profile lies in, as shown in the graphic below.
Start Angle = 0 End Angle = 180
Start Angle = 180 End Angle = 360
Revolved Surface Start/End Angles
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Revolved Surface
Follow the steps below to create a revolved surface. This example uses the file, Revolved Surface.MCX, which is included on your student CD. Step 1: Select the Create Revolved Surfaces function from the main menu or the Surfaces toolbar.
Create Revolved Surface
Step 2: Chain the profile to revolve, and then select the axis of revolution.
Step 3: Enter the Start Angle and End Angle. Use Flip to toggle between the angles entered and their inverse. Select Apply or OK when done. Profile Axis
Flip Start Angle End Angle
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Mastercam X6
Surface Modeling
Cross section cuts taken of revolved surfaces along the axis of revolution are arcs. Toolpaths created across revolved surfaces may take advantage of machine G18/G19 arc commands, significantly reducing G-code file size.
Use a Revolved surface when the shape can be formed by spinning a profile around a line.
Rules and Suggestions for Revolved Surfaces:
Multiple entities in the profile curve will result in multiple revolved surfaces. To create a single revolved surface, use the Create curves spline function to convert the curves to a spline before creating the surface. Revolved surfaces are very efficient types. Consider using a revolved surface to create rounded corners like those shown below, rather than using more complex surface types.
RevolveCorner.MCX
Revolved Surface on Rounded Corner
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Draft Surface
A Draft surface is formed by sweeping lines along a contour at a constant taper angle. Draft surfaces require only one drive curve.
Surface Shaded Drive Curves UV Curves
Legend
DraftSurf.MCX
Draft Surface
After chaining the profile to draft, the Draft Surface dialog box is presented. This dialog lets you control settings related to the surface including length and taper angle.
Consider using a Draft surface if the shape is a wall with a constant height and angle.
3-14
Mastercam X6
Surface Modeling
Run Length Length Draft Angle
Select Curves Length
Flip Length
Run Length Flip Angle
Angle Plane
Draft Surface Dialog Box
Item Select Curves Length Plane
Run Length Angle Split Draft Flip Length Flip Angle
Definition Re-select drive curves. Length from the top of the draft surface to the bottom, measured normal to the plane that the drive curves lie in. Define length of plane as distance from drive curves to a plane. When Plane is selected, a Plane icon appears. Click on this icon to select or define the plane. The length of the resulting surface walls. Mastercam automatically calculates run length based on length and angle. The angle of the wall from vertical. Extend and taper the surface in both directions. Flip draft direction. Flip angle direction.
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Rules and Suggestions for Draft Surfaces:
Avoid creating draft surfaces with very complex drive curve chains. These can become unwieldy or may fail to work altogether. Instead consider modeling the draft feature with several smaller and simpler draft surfaces. In cases where you want or need a single surface, you can usually convert the curves to a spline using the Create spline curves function. ID sharp corners will create overlapping surfaces when drafting inward. OD sharp corners can create gaps in the walls, as shown in the illustration below. If the design allows, this may be solved by creating a very small fillet (.001 inches) on the sharp corners.
Sharp Corner
Gap
Small Fillet
No Gap
Sharp Corners vs. Filleted Corners
3-16
Mastercam X6
Surface Modeling
Extruded surface works in a way similar to Draft surfaces with the following differences:
Extruded Surface
Extruded surfaces require a closed boundary profile. Draft surfaces do not. Extruded produces a closed (watertight) volume bounded by surfaces on all sides. Draft creates only wall surfaces. Extruded handles external sharp corners differently and do not produce gaps. Extruded offers more control including scale, rotation and offset from the original profile.
Surface Shaded Drive Curves UV Curves
Legend
ExtrudedSurf.MCX
Extruded Surface
Consider using an Extruded surface to create a drafted, watertight surface model.
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Chapter 3
Extruded surfaces are controlled by the following dialog box:
Select Curves Base Point Height
Flip Direction
Scale Rotate Offset Distance
Flip Offset
Angle Axis
Flip Angle
Line Two Points
Item Select Curves Base Point Height Flip Direction Scale Rotate Offset Angle Axis
Line Two Points
3-18
Definition Re-select drive curves. Allows selection of a point to position the surface. Distance from the top of the draft surface to the bottom, measured normal to the plane that the drive curves lie in. Flip extrude direction, offset or taper angle. Scales profile. Rotates profile. Offsets profile The angle of the wall from vertical. Activates the axis options. Select X, Y, Z or one of the following options. If not set, extrusion direction is normal to the Cplane the geometry is drawn in; not the active Cplane. Define axis using an existing line. Define axis using two points. Mastercam X6
Surface Modeling
Swept surfaces are formed by sweeping one or more contours, called Across contours, along one or more other contours, called Along contours. Along and across contours may be made up of lines, arcs, splines, or any combination of these.
Swept Surface
Surface Shaded Across Curves Along Curve
Legend
SweptMany.MCX
Swept Surface
Consider using a Swept surface when the shape can be formed by sweeping one or more (Across) contours through a trajectory of one or two other (Along) contours.
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Chapter 3
Swept Types
The following types of swept surfaces are supported. Many Across, One Along The example on the previous page is an example of this type of swept surface. One Across, One Along Swept surfaces can also be created by sweeping a single across contour along one along contour.
Surface Shaded Along Curve Across Curve
Legend Swept_1-Across_1-Along.MCX
Swept: One Across, One Along One Across, Two Along Swept surfaces can have a single across contour along two along contours. Surface Shaded Across Curve Along Curves
Legend Swept1-2.MCX
Swept: One Across, Two Along 3-20
Mastercam X6
Surface Modeling
Swept Surface with Sharp Corners Swept surface can now have sharp corners in the rails. Mastsercam now builds these types of surfaces, but breaks the surfaces in multiple pieces when necessary.
Swept surfaces are controlled by the ribbon bar shown here. Settings on this bar are only active for one along, one across swept surfaces. These control how the across profile is swept. Select Chain Translate Rotate Normal to Surface Two Rails Use Cplane
Rotate
Curves
Translate
Rotate vs. Translate Across Contour
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Item Select Chain Translate
Rotate
Normal to Surface
Definition Allows you to reselect chains Sets the movement of the across curve relative to the along curve. In the case of Translate the across curve sweeps down the along curve with no rotating or twisting Sets the movement of the across curve relative to the along curve. In the case of Rotate the curve can rotate and twist as it sweeps down the along curve. Specifies that the along curve lies on or over a surface and that the across curve will maintain a consistent relationship with the surface.
Two Rails
This is the only swept surface method that allows two along curves to control the across curve.
Use Cplane
Sets the Z axis of the current construction plane as one of the axes of the across curve’s moving coordinate system.
Rules and Suggestions for Swept Surfaces:
3-22
Cchain the across contour(s) first and then select OK in the chaining dialog box. Mastercam will prompt to select the along contour(s). Look for twists in the surface. Twisting may indicate that a Swept surface will not be appropriate for this shape. After creating the surface look at the UV curves to ensure they form an orderly path. Also use shading to check the result. Twists and inflections are usually easy to spot when the surface is shaded. Avoid overly complex Swept surfaces. Very complex along contours can result in an unwieldy surface.
Mastercam X6
Surface Modeling
A Fence Surface is a ruled surface that is created from a curve lying on a surface. The curve does not have to lie exactly on the surface. Mastercam allows control over the blend type, start and end heights and angles of the fence surface.
Fence Surface
Original Surface Fence Surface Curve
Legend
FenceSurf.MCX
Top View
Front View
Side View
Fence Surface
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Fence surfaces are controlled by the following ribbon bar: Chain Select Surface Flip Blend Method Start Height End Height Start Angle End Angle
Item Flip Blend Method
Start Height End Height Start Angle
End Angle
Definition Flips side of original surface the fence surface will be created on. Set the blending method for how the height and angle of the fence surface varies along the chain. Constant: Height and angle are constant along the curve. Linear taper: Height varies at a constant rate from the start to the end of the surface. Cubic blend: Height varies based on an S-shaped cubic blending function. Height of fence at start of curve. Height of fence at end of curve. Angle from perpendicular to the original surface at the start of the fence surface. Angle is leaning left or right from a direction perpendicular to the fence path. Angle from perpendicular to the original surface at the end of the fence surface.
Linear and cubic blending may appear similar on some shapes. The following diagram compares the three types along a flat surface. Constant Linear Cubic
Fence Blending Compared 3-24
Mastercam X6
Surface Modeling
The following diagrams show the different fence surface blending methods on a curved surface:
Constant
Linear
Cubic
Blending Method The following diagram shows how the fence can be tilted using the Angle setting. Linear and cubic blending permits a different start and end angle of the fence surface. Original Surface Fence (No Angle) Fence (-30 Angle) 90 Deg To Surface
Legend
Fence Surface Angle
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Fence surfaces have many useful applications. For example, a fence surface can be used to create surfaces to contain toolpaths within a boundary (containment surfaces) or extend toolpaths beyond the edges of the part (runoff surfaces). Below are some examples of fence surfaces: Start Height = 1.0 End Height = 0.0 Blending = Linear Start Angle = 0.0 End Angle = 0.0
Original Surface Fence Surface(s) Fencesurf1.MCX
Legend
Start Height = 0.1 End Height = 0.1 Blending = Linear Start Angle = 0.0 End Angle = 0.0 Fencesurf3.MCX
Start Height = 1.0 End Height = 1.0 Blending = Linear Start Angle = 0.0 End Angle = 0.0 Fencesurf4.MCX
Fence Surface Examples Rules and Suggestions for Fence Surfaces:
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If the curves do not lie exactly on the surface Mastercam will project them normal to the surface, not the active Cplane. To project the curves onto the surface normal to the active Cplane, use the Xform Project function before creating the fence surface. For trimmed surfaces, the projected curve is not automatically trimmed to the surface edges. If the curve extends beyond the surface edge, it is projected onto a linear extension of the surface so that the fence will be created along the entire length of the curve. Avoid abrupt turns in the fence surface by selecting only tangent and continuous curves. Mastercam X6
Surface Modeling
Net surfaces are created from a network of intersecting curves. Net surfaces are able to model very complex shapes, including freeform organic shapes used in consumer goods.
Net Surface
Skateboard.MCX
Netsurf3.MCX
Netsurf5.MCX
Net Surface Examples
Net surface should be the last surface you consider for modeling a shape. Consider using a Net surface when there are four or more intersecting curves that form the shape. Mastercam Handbook Volume 2
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Chapter 3
Net surfaces usually require at least two along and two across contours. An exception is when all the across contours meet at one or both ends. The location that curves meet at a single point is called an Apex point.
Apex Point
Netsurf6.MCX
Net Surface: One Across Contour
Net surfaces are controlled by the following ribbon bar: Apex Point Style
Item Apex Point Style
3-28
Definition Set when the net surface requires manual selection of an apex point. Determines the depth of the surface when selected curves do not intersect in Z. Across: Set depth from Across curves. Along: Set depth from Along curves. Average: Set depth as average of Across and Along curves.
Mastercam X6
Surface Modeling
Curves that do not form a rectangular mesh may require that you manually chain the contours in a specific way. An example of this is shown below. This is called a pole surface since all along contours meet at a common point.
Manual Chaining
The Along contour is the chain that forms the bottom of the bowl. The Across contour is the chain that forms the top of the bowl. It does not matter which order you pick the curves in, but you must select them pointing away from the common point in the bottom of the bowl. The contour that forms the top of the bowl does not have to be broken at the intersections with the across contours. In this case, select the contours in the order indicated. It is easier to chain these shapes by changing each contour to a different color and using the color mask chaining option.
5 1 4
2 3 Chaining Sequence
Netsurf7.MCX
Resulting Surface
Net Surface: Manual Chaining Pole Surface Mastercam Handbook Volume 2
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Chapter 3
Another way of using Net surface is to chain the curves as shown below. Three along contours run along the top and bottom of the bowl in the direction of its longest side. The across contours run along the bottom of the bowl in the direction of the shortest side. It is important to note that these two different chaining methods result in slightly different shapes.
1
2 4 3
Chaining Sequence
Netsurf8.MCX
Resulting Surface
Net Surface: 3-Along 1-Across Contour
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Surface Modeling
Net surfaces allow the curves to be open on one end, as shown in the example below. Be sure to indicate the apex point where the along curves intersect.
Open Contours
Apex Point
Netsurf9.MCX
Net Surface: Open Contours Rules and Suggestions for Net Surfaces:
If all the across contours meet at an apex point on one or both ends, select the Apex Point button before chaining. After chaining, Mastercam will prompt to select the apex point(s). Chain the contours in any direction or order. Window selection of the contours works for almost every possible shape. The contours can be open in the along direction only if all contours in the across direction are closed. A combination of open and closed contours in both directions will fail. Sharp corners in the contours will be ignored. Place a small radius on sharp corners. A maximum change in the tangent vector in a contour is 10 degrees. Angles greater than this will generate an error. Fillet sharp corners or smooth the contours to generate an angle less than 10 degrees. Mastercam Help provides more information and practical examples for the Net surface type.
Net Surface replaces and improves upon the Coons surface used in previous Mastercam versions. Coons surfaces can still be created using the C-Hook, CoonsSurf.DLL. A document on your student CD, CoonsSurf.PDF explains how to create Coons surfaces.
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Trimmed Surfaces
Trimmed surfaces get their name from how they are defined. They are based on the principle that a complex shape can be described more efficiently by storing it as two components instead of one. One component is called the Base (or Parent) surface. The other component is called the Trimming Boundary (ies). The base surface defines the shape of the trimmed surface. The trimming boundary defines the extents of the trimmed surface. Only the area inside or outside the trimming boundary is displayed to the operator, though the system maintains a definition of the base surface internally.
Base Surface
Boundaries
Trimmed Surface TrimSurf1.MCX
Trimmed Surface The following functions are used to create and alter trimmed surfaces:
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Trim Surfaces to Surfaces Trim Surfaces to Curves Trim Surfaces to a Plane Un-trim Surfaces Remove Boundary from Trimmed Surface Fill Holes with Surfaces Create Split Surface Surface Extend Create Flat Boundary Surface
Complex Part Modeled Using 172 Trimmed Surfaces Only
Mastercam X6
Surface Modeling
These functions are selected from the Create, Surface menu. Many are selectable from the Surfaces Toolbar shown here.
Item Trim Surfaces to Surfaces Trim Surfaces to Curves Trim Surfaces to a Plane Un-trim Surfaces Remove Boundary from Trimmed Surface Fill Holes with Surfaces Create Split Surface Extend Surface Create Flat Boundary Surface
Definition Trims surfaces to another group of surfaces. Trims surfaces to a contour. Trims surfaces to a Cplane. Un-trims and recovers the parent surface. Similar to Un-trim surfaces, but removes only the boundaries selected. Creates trimmed surfaces to fill. Breaks one surface into two surfaces. Extends the length of an existing surface. Creates a flat trimmed surface from a contour. Similar to Trims Surfaces to Curves, except there is no need to define a flat parent surface first.
Trimmed surfaces are one of the most powerful and flexible surface types. How powerful? Consider that surface models generated from Solid Modeling CAD systems often contain most or only trimmed surfaces.
Mastercam Handbook Volume 2
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Chapter 3
Trim Surfaces To Curves
Trim Surfaces to Curves trims an existing surface to one or more curves. Curves can be made of lines, arcs and splines. Mastercam prompts for the surfaces, then for the curves, and finally to indicate the area to keep. Click on the surface, move the mouse over an area that is to remain after trimming, and then click. Trim Surfaces to Curves is controlled by the following ribbon bar: Select Surfaces Select Curves Keep Original Delete Original View Normal Distance Extend Curves to Edge Split Model Keep Multiple Regions Use Current Attributes
Item Select Surfaces Select Curves Keep Original Delete Original View Normal Distance
Extend curves to edge Use Attributes
3-34
Definition Reselect the surfaces to trim. Reselect the trimming curves. Keep the original surface after trimming. Delete the original surface after trimming. This is the normal setting Trim by projecting the curves normal to the active Cplane. This is the normal setting. Trim by projecting the curves normal to the surface. When Normal is selected, this is the largest distance the curves can be from the surface and still be considered as a trimming curve. Usually used to control whether the curve trims through both walls of a cylindrical surface. If the curves do not extend to the edges of the surface, project them linearly to the edge. Apply the current construction attributes to the new surface. If not selected, the new surface will have the same drawing attributes as the original. Mastercam X6
Surface Modeling
The curves do not have to lie on the surface. Mastercam projects the curves onto the surface normal to the active Cplane or to the surface, depending on the Plane/Normal setting. The following illustrations show how both methods work:
Trimming Curve
Surface Shaded
Surface
Projection Path
Trimming Curves
Plane Indicator
Top
Iso
Legend
Projection Direction
Side Front
TrimToCurves_Plane.MCX
Trim to Curves - Project Normal to Plane
Trimming Curve
Surface Shaded Trimming Curves
Surface
Top
Projection Path
Iso
Legend
Projection Direction
Side Front
TrimToCurves_Normal.MCX
Trim to Curves - Project Normal to Surface Mastercam Handbook Volume 2
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Chapter 3
The Extend Curves to Edge setting allows trimming to curves that do not already extend to the edge of the surface, as shown in the diagram below: Linear Extension
Base Surface
Trimmed Surface ExtendToEdge.MCX
Extend Curves to Edge Split Model creates two trimmed surfaces broken along the curves.
Base Surface
Surface-1 Surface-2 SplitModel.MCX
Split Model Rules and Suggestions for Trim Surfaces to Curves:
3-36
Avoid boundaries that run along the edges of the surface. If needed, extend the surface beyond the curves before trimming. Very complex 3D boundaries may fail to trim. Try using Project to Plane to flatten the boundary first. Complex boundaries may fail to trim. Try converting the boundary to a spline first. Large numbers of trimming curves may fail to trim. Try selecting some of the curves, trimming, and then trimming the others. Use the Plane function instead of Normal whenever possible as it is more reliable.
Mastercam X6
Surface Modeling
Trim Surfaces to a Plane trims one or more surfaces to a Cplane.
Trim Surfaces to a Plane
Surface Plane
Legend
Right View Trim_SurfToPlane.MCX
Trim Surfaces to Plane Plane selection is controlled with the following dialog box which appears after selecting the surfaces to trim:
Line 3 Points Entities Normal Named Plane Flip Direction
Mastercam Handbook Volume 2
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Chapter 3
Item X Y Z Line 3 Points Entities Normal Named Plane Flip Direction
Definition Define a plane Parallel to the YZ plane at specified X value. Define a plane Parallel to the XZ plane at specified Y value. Define a plane Parallel to the XY plane at specified Z value. Define a plane based on an existing line. The plane will be perpendicular to the active Cplane and coplanar with the line. Define a plane given three points. Define a plane by selecting an arc, two lines, a 2D spline, or a flat surface. Define a plane normal to an existing line. Select a previously defined plane. Flip the plane normal direction.
Trim Surfaces to a Plane is controlled by the following ribbon bar: Select Surface Select Plane Keep Original Delete Original
Item Select Surface Select Plane Keep Original Delete Original Delete surfaces on Other side of plane Split Model Use Attributes
3-38
Delete Surfaces on the other side of the Plane Split Model Keep Multiple Regions Use Current Attributes
Definition Reselect surfaces to trim. Reselect plane. Keep the original surface after trimming. Delete the original surface after trimming. This is the normal setting Deletes selected surfaces that are not trimmed and that lie on the other side of the trimming plane. Divide surface(s) at plane rather than trim to plane. Apply the current construction attributes to the new surface. If not selected, the new surface will have the same drawing attributes as the original. Mastercam X6
Surface Modeling
Rules and Suggestions for Trim Surfaces to Plane: This function is very fast and reliable. Consider using it whenever possible. For example, use this function instead of trimming to a flat surface. Be sure to save your work before using any surface trim or blend function in case you have a problem.
Trim Surfaces to Surfaces trims one set of surfaces to another. One of the selection sets must be a single surface.
Trim Surfaces To Surfaces
Surfaces Not Selected
Areas to Keep Surfaces-2 Surface-1
Trim_SurfToSurf.MCX
Trim Surface to Surfaces This function is controlled with the following ribbon bar: Trim First Trim Second Trim Both First Surface Second Surface Keep Delete
Mastercam Handbook Volume 2
Extend Curves to Edge Split Model Keep Multiple Regions Use Current Attributes
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Chapter 3
Item First Surface Second Surface Keep Original Delete Original Trim First Trim Second Trim Both Extend Curves to Edge Split Model Use Attributes
Definition Reselects first surface or set of surfaces Reselects second surface or set of surfaces Keeps the original surface after trimming. Deletes the original surface after trimming. This is the normal setting Trims only the first surfaces. Trims only the second surfaces. Trims both sets of surface(s) to each other. If the curves do not extend to the edges of the surface, projects them linearly to the edge. Divides surfaces at surface rather than trim. Applies the current construction attributes to the new surface.
Mastercam will prompt to pick the first surface. Select the surface(s) to trim. Then select the second surface(s). One set must consist of a single surface only. After the surface is selected, a prompt appears to pick the area of the surface to keep. Click on a surface and drag the mouse into an area to keep and click again. Repeat for the second surface(s). Rules and Suggestions for Trim Surface to Surfaces:
3-40
One set of surfaces must contain only one surface. Do not include any surface that does not intersect with the trimming surface(s). This will cause an error, “Cannot Trim Surface, Selected curves do not form a closed boundary.” Consider using other trim methods first. Trimming to a plane, for example, may be a better option if one of the sets of surfaces is flat. If you have Mastercam Solids, consider modeling the shape in solids rather than surfaces. Trimming and filleting are generally more reliable in solids.
Mastercam X6
Surface Modeling
Flat boundary surfaces are trimmed surfaces created from curves only. Mastercam creates a flat base surface behind the scenes. The same rules and suggestions for Trim Surfaces to Curves apply for this function.
Flat Boundary Surfaces
Trimmed Surface
Boundaries
FlatSurf1.MCX
Flat Boundary Surface Un-trim surfaces recovers the base surface. Mastercam looks at the underlying (Blanked) base surface, recovers it, and removes the boundary from the definition.
Trimmed Surface
Un-trim Surfaces
Base Surface + Boundary Untrim.MCX
Un-Trim Surface
Mastercam Handbook Volume 2
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Chapter 3
Remove Boundary
Remove Boundary from Trimmed Surfaces reverses the trimming operation on one or more surface boundaries. After selecting the surface, Mastercam will prompt to “Slide to boundary which is to be removed”. Drag the mouse to the edge of the boundary to be removed and click once. When prompted to “Remove all internal boundaries” select yes to untrim all boundaries that lie completely within the surface. Slide Cursor to This Edge
Base Surface
Trimmed Surface
Remove Boundary
RemoveBndy.MCX
This function is usually used to allow the 3D surface toolpaths to flow over features that will be created using subsequent operations; for example, drilled holes, 2D toolpath cutouts, or details burned into a mold cavity with a sinker EDM.
Trimmed Surfaces
Boundaries Removed CellPhone_RemoveBndy.MCX
Remove Boundary to Facilitate Mold Cavity Milling
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Mastercam X6
Surface Modeling
Fill Holes with Surfaces can accomplish the same purpose as remove boundary but maintains the original trimmed surface. This makes it easier to display or hide the fill surfaces. Individual or all internal holes can be filled.
Fill Holes
Holes Filled with Surfaces
Surface with Holes
FillHoles.MCX
Fill Holes with Surfaces Split surface divides one surface into two trimmed surfaces. The split will be along the U or V line toggled by the flip icon on the following ribbon bar.
Split Surface
System Attributes Surface Attributes
Split Location
Two Trimmed Surfaces
Single Surface
Split Surface
SplitSurf.MCX
After the surface to split is selected, slide the mouse to the location where you want the split to be placed and click to sketch this location. Press the key on the keyboard to toggle Snapping on. This lets you select the exact location of the split by picking a geometric feature. Mastercam Handbook Volume 2
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Chapter 3
Surface Extend
Surface Extend lengthens a surface by a specified value or to a selected plane. The result is a trimmed surface that is either linear or shares the same radius of curvature as the surface being extended. These options are controlled with the following ribbon bar: Linear Non Linear Plane Length Keep Delete
Item Linear Non-Linear Plane Length Keep Delete
Definition Extend the surface in a linear direction, tangent from the edge. Extend the surface following the same radius of curvature at the edge of the surface. Extend to a plane. Length to extend. Keep the original surface. Delete the original surface.
The diagram below shows the difference between linear and non-linear surface extension.
Before
Linear
Non-Linear
Linear vs. Non-Linear Extension 3-44
Mastercam X6
Surface Modeling
Surfaces can be extended by a specified length, or until they intersect a specified plane. Plane selection uses the same dialog box shown on page 3-36.
Before
Length
Plane
Linear Extension Length vs. Plane An Offset Surface is a surface created by a specified distance from an existing surface. Many surfaces can be offset at once. The initial offset direction is set by the surface normal. Offset distance and direction(s) are controlled with the following ribbon bar:
Offset Surface
Select Distance
Single Flip Cycle/Next Flip
Item Select Single Flip Cycle/Next
Flip Distance Copy Move
Copy Move
Definition Re-select surface(s) to offset. Flip the offset direction of a single surface. Click to cycle through all selected surfaces to view the surface normal. Use the Single Flip to change the offset direction of the surface if needed. Change the offset direction of all selected surfaces. Amount of offset. Keep the original surface. Delete the original surface.
Mastercam Handbook Volume 2
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Chapter 3
Fillet Surface
A Fillet Surface is a surface that blends from an existing surface(s) onto one of the following:
Fillet Surfaces to Surfaces Fillet Surfaces to Curves Fillet Surfaces to a Plane
These functions are selected from the Create, Surface menu or from the Surfaces Toolbar shown below:
Item Fillet Surfaces to Surfaces Fillet Surfaces to Curves Fillet Surfaces to a Plane
Fillet Surfaces To Surfaces
Definition Fillet surfaces to another group of surfaces. Fillet surfaces to a contour. Fillet surfaces to a Cplane.
This function creates a surface that is tangent to two surfaces. This fillet can be a constant or variable radius. If multiple surfaces are selected in a set, Mastercam attempts to match surfaces in one set to the other. Mastercam prompts to select the first set of surfaces. Pick these and then either press on the keyboard or select End Selection. Then select the second set. Mastercam then displays the fillet surfaces to the surfaces dialog box.
3-46
Mastercam X6
Surface Modeling
The following illustration shows the Fillet Surfaces to Surfaces dialog box. Expand the dialog box to view the variable fillet options.
Expand/Contract First Set
Flip Normal
Second Set Radius Pick Pair
Options
Dynamic Radius Mid Point Radius Modify Radius
Variable Fillet Settings
Remove Radius Cycle Variable Radius
Fillet Surface Dialog Box
Mastercam Handbook Volume 2
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Chapter 3
The following parameters apply to all fillet surfaces: Item Expand/Contract Pick Pair
Flip Normal Trim Preview Join
First Set Second Set Options
Definition Show/Don’t show variable fillet options Provides for more specific selection of fillet solutions. With this option, you indicate a point near the solution you want after picking the surface. Flip side of surface fillet is on. Trims both surfaces back to the fillet. Previews result of fillet operation. Combines results into a single surface if possible. Uses the join tolerance set on the Options dialog box. Re-selects first set of surfaces. Re-selects second set of surfaces. Options for fillet surface creation. See following page.
The following parameters apply only to variable fillet surfaces: Item Radius Dynamic Radius Mid Point Radius Modify Radius Remove Radius Cycle Variable Radius
3-48
Definition The radius for a constant radius fillet surface or the start radius for a variable fillet surface. Assigns radii by dragging mouse along center curve of fillet. Assigns radius at midpoint of center curve of fillet. Changes a radius already assigned along the center curve. Removes a radius already assigned along the center curve. Toggles between radii assigned. Radius value to assign to points along the variable fillet.
Mastercam X6
Surface Modeling
Fillet options provide additional setting and controls over the fillet surface creation.
Item Entities
Find Multiples Fillet Both Sides Extend Surfaces
Join Results Trim Surface Original Surface Trim Surface(s) Delete surfaces on other side of plane
Definition Select entities to create. Fillet: Create a fillet surface. Rails: Create curves along the edges of the fillet. Center: Create a curve along center of the fillet surface. Surface Curve: Create surface curves Tells Mastercam to find and display multiple solutions. Create fillet surface on all sides of the surface, not just the Normal sides. Determines the types of entities created. If one surface boundary is outside another, a fillet surface is created on the outside boundary. Sets the tolerance for the Join option. Determines which surface sets are trimmed. Keep or delete the original surface. Trim back the first, second, or both surfaces to the fillet surface. Delete selected surfaces that are not trimmed by the slice plane and that lie on the other side of trim plane.
Mastercam Handbook Volume 2
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Chapter 3
Fillet Types
Constant radii fillets maintain the same radius at every point along the fillet surface. Variable radii fillets change radius at different points along the surface. If only two radii are specified, the radius changes at a constant rate from one side of the fillet to the other. If more than two radii are specified, the radius changes at points and values specified along the fillet. The following diagram shows three fillet types by blending two flat surfaces: Surface-1
Surface-2 Original Surfaces FilletSurface.MCX
Fillet Surface Constant Radius
Variable Radius (Two Radii)
Variable Radius (Three Radii)
Fillet Surface Types 3-50
Mastercam X6
Surface Modeling
Selecting any of the variable fillet buttons causes markers as shown in the diagram below. These help you visualize and set radius changes along the length of the fillet.
Variable Fillet Indicators
The dashed line runs along the center of the fillet radius. Vertices indicate where radii change. As you toggle between the vertices, a radius value displays the radius of the fillet at that point.
Fillet Preview Radius Centerline
0.75000 0.75000
Radius Value Surface Normal
0.25000
Legend
0.75000 0.25000 0.75000
Variable Fillet Indicators Mastercam Handbook Volume 2
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Chapter 3
Variable Radius Fillet
Follow the steps below to create a variable fillet surface. This example uses the file, FilletSurface.MCX, which is included on your student CD. Step 1: Select the Fillet Surfaces to Surfaces from the main menu or the Surfaces toolbar. Step 2: Select one of the surfaces and then press or select End Selection. Repeat for the other surface. Surface 1
Surface 2
FilletSurface.MCX
Step 3: A preview showing a constant radius fillet surface with the system default .25 radius is displayed. Check the Variable Fillet option on the fillet surfaces dialog box.
3-52
Mastercam X6
Surface Modeling
Step 4: Select the Midpoint Radius marker button to insert a radius change halfway between Radius Marker-1 and Radius Marker-2. Pick one radius marker and then the other. Radius Marker-1 Radius Marker-2
Mid point Radius
Step 5: Click on the Cycle button. You will be prompted to enter a radius for the first, middle, and last radius. Enter values of .75, .25, and .75 respectively. The fillet preview will update to show the radius changes. If you make a mistake, simply select Cycle again and re-enter any radius values that are not correct. Finally, select OK to complete the fillet.
0.75000 0.25000 0.75000
Mastercam Handbook Volume 2
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Chapter 3
Fillet To Plane
Fillet Surface to a Plane is a very reliable way of creating a fillet between surfaces and a flat area. Consider using this function rather than Fillet Surfaces to Surfaces if one of the surfaces is flat. This function uses the plane select dialog box used by trim to plane described on page 3-36, and the fillet dialog box used by fillet surfaces described on page 3-46.
Original Surface Fillet Surface Plane Indicator
Legend
FilletToPlane.MCX
Fillet to Plane
3-54
Mastercam X6
Surface Modeling
Fillet Surfaces to Curves blends the surface onto a curve. This function uses the chaining and Fillet Surface dialog boxes that you are already familiar with.
Fillet To Curves
FilletToCurve.MCX
Fillet Surface to Curve
Rules and Suggestions for Fillet Surfaces:
Fillet surfaces are some of the more complex types of surface modeling functions, and require considerable skill and practice to become proficient with. Solid modelers in general do a much faster and easier job of creating complex fillets than surfaces. Consider modeling the part as a solid whenever complex filleting is required. With the emergence of solid modelers and direct CAD translators, the need for machinists to do surface modeling has decreased. Most modeling done by machinists is to fix a surface or area that was not translated properly, or to fill holes and gaps or create runoff surfaces to facilitate machining or part holding. Always try to use the simplest and most reliable surface type that will do the job. For example, you may fillet a surface to a plane rather than to a flat surface.
Mastercam Handbook Volume 2
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Chapter 3
2 Surface Blend
Use a 2 Surface Blend to create a surface that smoothly blends between two surfaces when no other connecting information is known. Mastercam prompts for a surface to blend onto. Pick one of the surfaces, and then move the cursor indicator to the point on the surface where you want the blend to begin. In the illustration below that point is at the facing surface edges, but it could be anywhere along the surface. Repeat for the second surface. Use the Surface Blend dialog box to control the blend surface.
Surface-2
Surfaces Blend Edge
Surface-1
Cursor Position
Legend 2SurfBlend.MCX
Two Surface Blend
3-56
Mastercam X6
Surface Modeling
The 2 Surface Blend dialog box sets the blend surface direction, magnitudes, and other parameters to control the shape, start points, and direction of the blend surface.
Surface-1 Surface-2 Surface-1 Magnitude
Surface-2 Magnitude
Twist Modify Endpoints
Item Surface-1 Surface-2 Twist Modify Endpoints Trim Surface(s) Keep Curves Magnitude-1
Magnitude-2
Definition Reselects Surface-1 Reselects Surface-2 Flips endpoints to correct for a twisted surface. Reselects the endpoints of the blend surface. Trims first, second or both surfaces to the blend surface if blend is mapped away from the surface edge. Draws splines along the blend surface edges. Sets the initial strength or velocity of the reference splines at their start position. The magnitude values change the shape of the blend surface. Sets the strength of the reference splines at their end position.
Mastercam Handbook Volume 2
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Chapter 3
The following illustrations show the effects of changing parameters on the blend dialog box.
Flip Spline Direction
Change Twist
Change Magnitude
3-58
Mastercam X6
Surface Modeling
The 3 Surface Blend function works similar to 2 Surface Blend. Because of the complexity of this type of blend, multiple surfaces are created to fill the area.
3 Surface Blend
As each surface is picked, Mastercam prompts: Press to flip spline direction or press . Press F on the keyboard if needed so the spline is perpendicular to the blend surface edge. You can always flip the directions using the 3 Surface Blend dialog box.
Surface-2
Surfaces
Surface-1
Blend Edge Cursor Position
Surface-3 Legend 3SurfBlend.MCX
Three Surface Blend
Mastercam Handbook Volume 2
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Chapter 3
The 3 Surface Blend dialog box sets the blend surface direction, magnitudes, and other parameters to control the shape, start points, and direction of the blend surface.
Surface-1 Surface-2 Surface-3
Twist Modify Endpoints
Item Surface-1 Surface-2 Surface-3 Twist Modify Endpoints Trim Surface(s) Keep Curves Magnitude-1
Magnitude-2 Magnitude-3
3-60
Surface-1 Magnitude Surface-2 Magnitude Surface-3 Magnitude
Definition Reselects Surface-1 Reselects Surface-2 Reselects Surface-2 Flips endpoints to correct for a twisted surface. Reselects the endpoints of the blend surface. Trims first, second, or both surfaces to blend surface if blend is mapped away from the surface edge. Draws splines along the blend surface edges. Sets the initial strength or velocity of the reference splines at their start position. Magnitude values change the shape of the blend surface. Sets the strength of the reference splines at their end position. Sets the strength of the reference splines at their end position.
Mastercam X6
Surface Modeling
3 Fillet Blend creates what is called a rolling ball fillet. These are used to blend corners like those shown in the box below. These corners must have been created using the Fillet Surface function.
3 Fillet Blend
This blend type looks similar to a three surface blend, but 3 Fillet Blend automatically calculates the location where the blend surface(s) are tangent to the fillet surface. Simple three fillet blends can be filled with a single three sided surface.
2
1 3
Three Fillet Blend
3FilletBlend.MCX
Either a three or six sided blend surface can be created. The six-sided solution may give smoother results in some cases.
6-Sided Fillet Blend
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Chapter 3
The 3 Fillet Blend dialog box appears after the three fillet surfaces are selected.
Item Reselect 3 6 Trim Surfaces Keep Curves
Definition Reselects all three surfaces. Creates a three sided patch using one surface. Creates a six sided patch using multiple surfaces. Trims fillet surfaces back to patch surface(s). Keeps the edge curves created on the patch surface.
Solid modeling technology is generally superior to surface modeling for creating complex fillets. It is faster, more reliable, and will often produce better results. Whenever possible, use solids to create complex fillets. Surface modeling fillets are now used mostly to create patches to fill voids or create features to aid the machining of surface models when solid geometry is not available.
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Mastercam X6
Surface Modeling
While solids offer numerous advantages over surface models, surfaces can provide advantages over solids for creating toolpaths.
Surface From Solid
They may provide much more flexibility when machining complex shapes, such as an aerospace, prototypes and molds. For example, it can be easier to contain the toolpath within a defined area with surfaces. It can be easier to fill or remove certain features with surfaces. Surface toolpaths may calculate and regenerate faster than toolpaths from solids. Some 5-axis toolpaths require surfaces or curves and cannot use solid faces. It is not uncommon to decompose a solid model to surfaces for creating machining toolpaths. Use this function to create surfaces on the faces of a solid. There is no dialog box associated with this function. Simply pick the entire solid or specific faces and select OK or . It is a good idea to change levels first so the surfaces are created on a level different from the solid.
Solid
Surfaces
Create a Surface from Solid
Mastercam Handbook Volume 2
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Chapter 3
What You Learned
This chapter provided you with the basic knowledge and skills you need to create and modify surfaces, including:
3-64
The difference between wireframe and surface geometry. Surface definitions including drive curves, UV lines, and surface normal. How to identify and create basic surfaces including Ruled, Lofted, Revolved, and Draft. How to identify and create advanced surfaces including Swept, Net, Fence, Trim, Fillet, and Offset surfaces. Create surfaces that blend between a plane, curve or other surface(s). Recognize which surface type(s) are suitable given the wireframe geometry and part feature requirements. Trim surfaces to a curve, plane, or other surfaces. Extend split and un-trim surfaces. How to create a constant or variable radius fillet surface. How to blend two or three surfaces. Remove trim surface boundaries and fill holes in surfaces. Create surfaces from a solid.
Mastercam X6
Surface Modeling
Exercises: The following files are included on your Handbook Vol 2 Student CD. Refer to the diagrams and instructions in this chapter to create the surface or execute the surface modification described. Ruled-1.MCX RuleToPoint.MCX LoftWing.MCX RevolveSurf.MCX RevolveCorner.MCX DraftSurf.MCX ExtrudedSurf.MCX SweptMany.MCX Swept1-1.MCX Swept2-1.MCX FenceSurf.MCX FenceSurf1.MCX FenceSurf3.MCX FenceSurf4.MCX NetSurf3.MCX NetSurf5.MCX NetSurf6.MCX NetSurf7.MCX NetSurf9.MCX TrimSurf1.MCX TrimToCurves_Plane.MCX TrimToCurves_Normal.MCX ExtendToEdge.MCX SplitModel.MCX Trim_SurfToPlane.MCX Trim_SurfToSurf.MCX FlatSurf1.MCX Untrim.MCX RemoveBndy.MCX Cellphone_RemoveBndy.MCX FillHoles.MCX SplitSurf.MCX FilletSurface.MCX FilletToPlane.MCX FilletToCurve.MCX 2SurfBlend.MCX 3SurfBlend.MCX 3FilletBlend.MCX Skateboard.MCX Mastercam Handbook Volume 2
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Chapter 3
NosePuck.MCX 2BladeProp.MCX
Notes:
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Mastercam X6
Thank you for previewing the
Mastercam X6 Handbook Volume 2. We hope you like what you see. If you haven’t already, be sure to check out the Table of Contents included at the beginning of this sample for a full listing of topics covered. If you found this excerpt useful, we’re certain the rest of the book will help you along your way to mastering Mastercam. To thank you for considering our Mastercam Training Solutions,
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