Advanced 3D Geometry Modifying Geometry, Advanced Features and Body Operations

1
Advanced 3D GeometryModifying Geometry,
Advanced Features and Body Operations

• Chapter 5

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3D GeometryContents

• Modifying 3D Geometry
• 3D Curve Feature
• Planar Bodies
• Named Selection Base Objects
• Pattern Feature
• Advance Features
• Advanced Tools
• Body Operations
• Workshop 5-1, Enclosure Operation
• Workshop 5-2, Pattern Operation
• Workshop 5-3, 3D Curve

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3D GeometryModifying 3D Geometry

• Thin/Surface
• The Thin/Surface feature has two distinct
  applications
• Create thin solids (Thin).
• Create simplified shelling (Surface).
• Selections available from Details
• Faces to Remove selected faces will be removed
  from their bodies.
• Faces to Keep selected faces will be kept, while
  unselected faces are removed.
• Bodies Only the operation will be performed on
  the selected bodies without removing any faces.
• When converting solids into thin solids or
  surfaces you can specify a model's thickness in
  one of three offset directions
• Inward
• Outward
• Mid-Plane

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3D GeometryModifying 3D Geometry

• Thin/Surface details

Basic operation
Direction for thin solid or offset
Thickness or Thickness/Face Offset
IMPORTANT! To create surface geometry (NOT thin
solids) the Thickness field must be set to zero
(0). Examples . . .
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3D GeometryModifying 3D Geometry

• Using the simple block shown here lets look at
  basic Thin/Surface behavior.

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3D GeometryModifying 3D Geometry

• After generating the feature notice
• The end face is removed
• Thickness 2 mm
• Direction is toward original solids center
  (inward)
• Result is still a solid
• By changing the thickness field to zero and
  re-generating
• True surface model results

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3D GeometryModifying 3D Geometry

• Notes on Thin/Surface
• The Thin/Surface feature supports thickness gt 0
  if the selected faces are part of surface bodies.
  
• This allows for the thickening of an imported
  surface.
• Mid Plane Option
• This does not mean midplane extraction.
• Bodies will be hollowed, such that the inner and
  outer walls of the bodies are offset equal
  distances from the original faces.
• Example

Resulting offset is in both directions.
Solid body selected for Thin/Surface midplane
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3D GeometryModifying 3D Geometry

• Fixed Radius Blend
• The Fixed-Radius feature allows you to create
  blends on model edges.
• You can select or preselect 3D edges and/or faces
  for blending.
• Face selection applies blend to all the edges
  from that face.
• When preselecting, additional options are
  available from a RMB context menu (face edge loop
  selection, smooth 3D edge chain)
• You can edit the blend radius in the Detail View.
  Clicking Generate completes the feature creation
  and updates the model.
• Variable Radius Blend (same as above plus)
• Use the Detail View to change the start and end
  blend radius for each edge. Also, the Detail View
  can set the transition between blends to smooth
  or linear. Clicking Generate completes the
  feature creation and updates the model.
• Examples . . .

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3D GeometryModifying 3D Geometry
Face selected for fixed blend. All edges receive
blend
Details specify blend radius
Edges selected for fixed blend.
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3D GeometryModifying 3D Geometry
Linear Transition
Smooth Transition
Variable radius blend
If multiple edges selected for VR blend each is
listed in Detail
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3D GeometryModifying 3D Geometry

• Chamfer
• The Chamfer feature allows you to create planar
  transitions (or chamfer face) across model edges.
• You can select or preselect 3D edges and/or faces
  for chamfering.
• If a face is selected, all the edges from that
  face are chamfered.
• When preselecting, additional options are
  available from a right mouse button context menu
  (face edge loop selection, smooth 3D edge chain)
• Every edge on a face has a direction. This
  direction defines a right and left side.
• Chamfer is defined either by two distances from
  the edge for the planar transition (chamfer
  face), or by a distance (left or right) and an
  angle.
• The type of chamfer is set up in the Detail View
  along with the distances and angle.
• Examples . . .

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3D GeometryModifying 3D Geometry
Chamfer options (3)
Left
Right
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3D Geometry 3D Curve Feature

• gtConceptgt3D Curve
• 3D Curves can be used for
• Custom curves for Concept Modeling
• Base Object in Modeling a Feature
• Create 3D curves (Line Bodies) from
• Existing Model points
• Coordinates (text) File
• Curve passes thru all points in the chain.
• All points must be unique
• Curves may be either open or closed.

Closed Curve
Open Curve
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3D Geometry3D Curve Feature - Existing Points

• gtDefinitiongtPoint Select
• Select (and gtApply) existing model points
• Hold ltCTRLgt key to select multiple points.
• Curves may be either open or closed. (RMB)
• Resulting curve passes thru all selected points.

RMB
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3D Geometry 3D Curve Feature - Point File Method

• gtDefinitiongtFrom Coordinates File
• 3D curve created by XYZ coordinates in a text
  file.
• Format of Coordinates (text) File
• indicates Line is a comment
• Empty lines are ignored
• A data line consists of 5 fields, separated by
  spaces or tabs
• A) Group (integer)
• B) Point Number (integer)
• C) X coordinate
• D) Y coordinate
• E) Z Coordinate
• Notes
• A data line with the same group and Point is in
  error. Must be unique
• For a closed curve, the point number of last line
  should be zero.
• Coordinate fields ignored.

Group 2, closed curve example file A B C
D E 2 1 100.0101
200.2021 15.1515 2 2 -12.3456 .8765
-.9876 2 3 11.1234 12.4321 13.5678 2
0
Example SineCurve xyz data points
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3D Geometry Planar Bodies

• Planar bodies are surface bodies in the XY-plane.
  
• Planar bodies created in DM are used to perform
  2D Sim.
• Plane Strain, Plane Stress, Axisymmetry
• Numerically more efficient Sim models compared to
  full 3D models.

Solid
Planer
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3D Geometry Named Selection Base Objects

• Named Selections can be used as base objects
  (Groups) for basic modeling features.
• The named selection may contain either Bodies,
  Faces, Edges, or Points.
• Named Selections may be transferred to Sim
• must be selected in Default Geometry Options in
  environment Project Page or used in the creation
  of some features.

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3D Geometry Pattern Feature

• Pattern feature allows you to create copies of
  faces or bodies in
• Linear (direction offset distance)
• Circular (rotation axis angle)
• Can set anglezero to get auto-calculated evenly
  spaced instances
• Rectangular (two sets of directions offsets)
• For face selections, each copied instance must
  remain coincident with the originating body
  (must touch same base region).
• Each copied face incidence must not
  touch/intersect each other

Linear Circular
Rectangular
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3D Geometry Pattern Copies

• Easy to change the Copies (in Details) and
  gtGenerate.
• Total Copies 1

5
9
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3D GeometryAdvanced Features

• Two Advanced Feature Properties described in this
  section apply selectively to the 3D Features
• Target Bodies Extrude, Revolve, Sweep,
  Skin/Loft, Slice, Import Attach.
• Merge Topology Extrude, Revolve, Sweep,
  Skin/Loft.
• Target Bodies allows users to specify which
  bodies are operated on during a Cut, Imprint, or
  Slice operation.
• By switching the value of the Target Bodies
  property from All Bodies to Selected Bodies,
  the user can select bodies through another
  Apply/Cancel property called Bodies.

Cut operation applied only to Selected Bodies
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3D GeometryAdvanced Features

• Merge Topology Detail property for Extrude,
  Revolve, Sweep, Skin
• A Yes/No detail option that gives control over
  feature topology.
• gtYes optimizes the topology of feature bodies.
• gtNo leaves the topology of feature bodies
  unaltered.
• The default setting for Merge Topology differs
  depending on the 3D feature you are using
• Extrude default is Yes
• Revolve default is Yes
• Skin/Loft default is No
• Sweep default is No
• Example follows . . .

Note In version 7.0 and earlier Merge Topology
is a read-only property whose behavior is, inner
profile faces are merged but outer profile faces
are not. This means that features created in 7.0
and older versions cannot be changed
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3D GeometryAdvanced Features
Topological Control
Merge Topology gtYes
Merge Topology gtNo

• Setting the value to gtYes optimizes all topology
  of the feature body. It is however, recommended
  to leave this setting as gtNo (default) for the
  Skin/Loft and Sweep features.
• Use caution when changing the value of the Merge
  Topology property.
• Once other features depend on this, faces and
  edges may appear or disappear and cause failures
  and invalid selections for subsequent features.

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3D GeometryAdvanced Tools

• Advanced operations are available via the gtCreate
  and gtTools Menu
• Freeze
• Unfreeze
• Named Selection
• Joint
• Enclosure
• Fill
• Surface Extension
• Winding Tool
• Pattern
• Body Operation
• Slice
• Face Delete

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3D GeometryAdvanced Tools

• Normally, a 3D solid feature operates like this
• Create the bodies of the 3D feature (e.g., an
  Extrude feature)
• Merge the feature bodies with the existing model
  via Boolean operations Add Material, Cut
  Material, Imprint Faces
• The Freeze feature allows you to control the
  second step acting as a separator in the
  construction history as displayed in the Feature
  Tree.
• Bodies created from features before a Freeze will
  become frozen
• Frozen bodies are denoted by the ice cube icon
  next to the bodys branch of the Feature Tree
• All frozen bodies are ignored by Add, Cut, or
  Imprint Material operation for any features
  following the Freeze
• An example . . .

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3D GeometryAdvanced Tools
Modeling history Model began with imported
geometry. An extrusion was added A freeze was
inserted A second extrusion was created adjacent
to the imported geometry
Frozen
Unfrozen
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3D GeometryAdvanced Tools

• Unfreeze allows one to selectively remove the
  freeze from single or multiple bodies (freeze is
  a global operation)
• Assembly notes
• By default if you import an assembly from a CAD
  package the assembly will remain as separate
  parts in DM without freezing
• Any subsequent 3D modeling operation however will
  result in a merge of any touching bodies in the
  assembly
• This can be avoided with the Freeze and Unfreeze
  tools

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3D GeometryAdvanced Tools

• Named Selections
• Can group entities under a single name
• Group can be transferred to Simulation

DesignModeler
Simulation
Note, DM allows different entity types to be
grouped (points, edges, surfaces), whereas
Simulation does NOT. Simulation will split
non-homogenous groups.
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3D GeometryAdvanced Tools

• Joint Feature
• Joins surface bodies together (for proper
  treatment in Simulation)
• Active or frozen bodies are eligible
• Topology can be shared (common mesh) or not
  (contact region)
• Example

Surface model consists of 3 surface bodies.
Edges along 2 bodies contact faces on the third.
Without the joint feature, in Sim the mesh would
be discontinuous at the interface (no nodal match
up).
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3D GeometryAdvanced Tools

• Using the share topology gtYes (default) the
  mesh along the boundary in Simulation is
  continuous
• Using share topology gtNo allows the
  edge/surface boundary to be modeled using contact
  elements (note face/edge detection must be set to
  gtYes)

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3D GeometryAdvanced Tools

• Enclosure
• Creates surrounding region around bodies to
  facilitate simulation of field regions
• CFD, EMAG, etc
• Box, sphere, cylinder or user defined shapes can
  be employed
• Cushion property allows the boundary extent to be
  specified (must be gt 0)
• Apply enclosure to all bodies or only selected
  targets
• Merge property allows for automatic multi-body
  part creation
• Ensures original part and enclosure will have
  nodal match up when meshed

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3D GeometryAdvanced Tools

• Example

Circuit board model
Cutaway view of enclosure
Enclosure created using box option
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3D GeometryAdvanced Tools

• Fill
• Creates frozen bodies that fill interior voids
  such as holes
• Works with active or frozen bodies
• Works only with solid bodies
• Useful for numerous CFD applications
• Example

Goal is to model the interior (fluid region) of
the valve block shown here
The desired (37) interior faces are selected then
the Fill is inserted
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3D GeometryAdvanced Tools

• Example (cont.)

Resulting fill is frozen (meshable) body
Interior region, now isolated, can be taken to
Simulation for meshing
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3D GeometryAdvanced Tools

• Winding Tool, for use with ANSYS Workbench - EMAG
• Creates a Winding Body (a special Line Body)
• Represents loops of wire, for instance, wire
  wound thru a rotor or stator
• First create a model of rotor or stator including
  the center plane that defines the alignment of
  the winding bodies.

Line Bodies are automatically named using phase
coil from the winding table.
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3D GeometryAdvanced Tools

• Then use Winding Tool to open the Winding Table
  file
• Winding Table is a text file.
• The Line Bodies are automatically named using
  phase coil from a winding table.
• Winding Tool is fully covered in ANSYS Workbench
  - Emag Course

Example Winding Table
Resulting Line Bodies
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3D GeometryAdvanced Tools

• Surface Extension
• Creates a surface extension based on edge
  selection
• Extension can be fixed or to selected faces
• Example

A thin solid model is converted to a mid plane
surface model
The result is a gap at the intersection of the 2
parts
Extending the circular edge closes the gap
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3D GeometryAdvanced Tools

• Face Delete
• Can remove features such as blends and cuts by
  removing faces from the model - - then heal the
  resulting wound
• If a suitable extension cannot be determined, the
  feature will report an error stating that it
  cannot heal the wound
• Used to defeature (simplify) imported models
  (e.g. remove a hole)
• If desired the hole could be recreated in DM to
  parameterize it

Example (delete blends and hole feature)
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3D GeometryAdvanced Tools

• Slice feature
• Slice is only available when the model consists
  entirely of frozen bodies
• Slice has two options
• Slice By Plane Select a plane and the model is
  sliced by this plane
• Slice Off Faces Select faces on the model and DM
  will slice off these faces then attempt to
  create a separate body from them

Result is 3 solids. Each blend becomes solid
region
Original geometry, one solid
2 blends chosen for slice
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3D GeometryAdvanced Tools

• Slice by Plane example
• Original imported Parasolid geometry (typically)
  does not lend itself to mapped (sweep) meshing in
  Simulation

Resulting FE mesh all tets
Imported geometry in DM
1 Body
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3D GeometryAdvanced Tools

• Use Slice operation to divide body into 4 bodies
  (single Part)

Original (frozen) geometry is divided via 2 Slice
operations
Result 3 bodies (Brick) swept meshed for Sim
1 body tet mesh
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3D GeometryBody Operations

• Body Operation allows users to manipulate bodies
  via 8 different options (not all will be
  available at all times)
• Any type of body can be used with Body
  Operations, (active or frozen).
• Point Feature points, attached to the faces or
  edges of the selected bodies, are not affected by
  the Body Operation
• Bodies and Planes are selected via the Details
  View
• Options include
• Mirror, Move, Copy, Delete, Scale,
• Cut Material, Imprint Faces, Slice
  Faces.
• Each described next . . .

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3D GeometryBody Operations

• Mirror
• User selects bodies and a mirror plane.
• DM creates copies of the selected bodies that are
  reflections of the original bodies in the mirror
  plane.
• Active bodies that are reflected will be merged
  with the active model.
• Frozen bodies that are reflected will not be
  merged.
• By default, the mirror plane is initially the
  active plane.
• Example selected surface here is mirror plane.

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3D GeometryBody Operations

• Move
• Users select bodies and two planes a source
  plane and a destination plane.
• DesignModeler will transform the selected bodies
  from the source plane to the destination plane.
• This is especially useful for aligning imported
  or attached bodies.
• Example
• Two imported bodies (a box and a lid) dont
  align.
• Maybe they were exported separately from a CAD
  system in two different coordinate systems.
• Problem is corrected in gtMove Body Operation.

1
2
1,2
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3D GeometryBody Operations

• Copy same as the Move operation except that
  copies of the bodies are moved while the original
  bodies remain unaltered.
• Delete users select bodies to delete from the
  model.
• Scale users select bodies to scale, then select
  a scaling origin through the Scaling Origin
  property.
• This property is a combination box with three
  options
• World Origin The origin of the global coordinate
  system is used.
• Body Centroids Each body is scaled about its own
  centroid.
• Point User can select a specific point, (2D
  sketch point, 3D vertex, or PF Point) to use as
  the scaling origin.

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3D GeometryBody Operations

• Cut Material
• Users select bodies for a cut operation from the
  active bodies in the model.
• Body Operation's Cut Material option works the
  same way as Cut Material does for any of the
  basic features.
• Example
• Airplane body is selected to cut from the block
  to form a mold

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3D GeometryBody Operations

• Imprint Faces
• Body Operation's Imprint Faces option works the
  same way as Imprint Faces does for any of the
  basic features.
• This option is available when active bodies exist
  in the model.
• In this example, the selected body is used to
  imprint the faces of the block

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3D GeometryBody Operations

• Slice Material
• Slice operations are performed on a completely
  frozen model.
• Body Operation's Slice Material operation works
  the same as Slice Material does for any of the
  basic features.
• Option is available only when all bodies in the
  model are frozen.
• Example of a slice operation airplane body is
  selected to slice the block

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Workshop 5-1, Enclosure Operation

• Goals
• Import a model in Parasolid format
• Use the enclosure operation to create a solid
  region representing the models surrounding field

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Workshop 5-1, Enclosure Operation

• Start Page
• Choose the Geometry icon to start a new DM
  session or gtFilegtNew
• When prompted select meter as the length unit

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Workshop 5-1, Enclosure Operation

• Import the Parasolids file blade.x_t.
• Main menu gtFilegt Import External Geometry File
  . . . Browse to file blade.x_t and open.
• gtGenerate the import.

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Workshop 5-1, Enclosure Operation

1. From the Tools menu choose Enclosure
2. Choose Cylinder from the shape field in the
   details window
3. Generate the enclosure

Note we left the cushion field set to the
default 1m. Larger or smaller bounding
enclosures can be defined using this field.
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Workshop 5-1, Enclosure Operation
With the enclosure generated, notice there are
now 2 bodies in the tree, one frozen (the
enclosure) and one active (the blade)
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Workshop 5-1, Enclosure Operation

1. From the tree highlight the active solid (the
   blade), RMB and Hide Body

With the blade hidden it can be seen that the
enclosure contains a void representing the
boundaries of the structure. This enclosure is
suitable for meshing in Sim.
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Workshop 5-2, Pattern Operation

• Goals
• Import a model in Parasolid format
• Add a hole and then use the Pattern Operation to
  upgrade the part to a Bolted Flange interface.

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Workshop 5-2, Pattern Operation

• Start Page
• Choose the Geometry icon to start a new DM
  session
• Or, use gtFilegtNew if already in DM
• Specify mm as the length unit

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Workshop 5-2, Pattern Operation

• Import the Parasolids file fan_hub.x_t.
• Main menu gtFilegtImport External Geometry File .
  . . Browse to file fan_hub.x_t and open.
• Generate the import.

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Workshop 5-2, Pattern Operation

1. Select the large Annular face
2. Click the New Plane Toolbar
3. Generate the new plane
4. Switch to gtSketching mode
5. Draw an 8 mm diameter circle on the face and
   position the circle 17 mm from the vertical and
   horizontal axes.

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Workshop 5-2, Pattern Operation

• Click the Extrude toolbar
• Change Operation to Cut Material
• Change Type to Through All
• gtGenerate the (first) hole
• The first hole is made, now get prepared to
  gtPattern (copy) it around.
• Reorient the model and/or click on the Blue ISO
  Triad Ball as desired.
• In the gtTree, click on ZXPlane to make it active
  - - a useful axis appears.

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Workshop 5-2, Pattern Operation

• Use the select filter as necessary to select the
  holes cylindrical bore surface.
• gtCreategt Pattern
• From the Details menu
• gtGeometrygtApply
• The hole was already selected
• Change the Pattern type to Circular
• Select the axis that goes thru the large hole in
  the center of the part and click on gtApply
  (note, if you dont see an appropriate axis, you
  may have to activate ZX or YZ Plane in the tree).
• Change Copies to 5 (note you will get 6 holes
  total - - this includes the original plus 5
  copies)
• gtGenerate to create hole pattern

Final
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Workshop 5-3, 3D Curve

• Goals
• Utilize a 3D Coordinate point file to generate a
  3D curve.
• Use gtSweep to create a new part from the curve.
• Extrude, Revolve, etc, could similarly be used

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Workshop 5-3, 3D Curve

• Start Page
• Choose the Geometry icon to start a new DM
  session
• Or gtFilegtNew
• When prompted select mm as the length unit

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Workshop 5-3, 3D Curve

• gtConceptgt3D Curve
• In Details,
• gtDefinition should be From Coordinates File
• At gtCoordinates File click to
  browse
• Browse as necessary to file sine_points.txt and
  gtOpen it
• gtGenerate the 3D Curve Line Body

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Workshop 5-3, 3D Curve

• From the Tree, select the Curve1 3d Curve
• Name the selection
• gtToolsgtNamed Selection
• In the Tree, select Line Body under
  1 Part, 1 Body
• Click Apply in the Details window for Geometry
• Click gtGenerate

5
4
6
7
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Workshop 5-3, 3D Curve

1. Select XYPlane from the tree
2. Select NamedSel1 from the tree
3. Click on Revolve
4. Select the Y-axis
5. Click gtApply in the Details window for Axis

8
10
9
11
12
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Workshop 5-3, 3D Curve

• Select FD1, Angle in the Details window and
  enter a value of 360 to replace the default
  value.
• gtGenerate the surface

Resulting 3D Surface Body
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