Groundhog Day All Over Again.2 (Part 2)

The Pros and Cons of different approaches to duplicate NX11 model shapes.

Overview

We left off in “Part 1” of “Groundhog Day All Over Again .2” discussing the need to increase productivity by eliminating the non-productive and making efficient the inefficient. CAD users now have the ability literally drag and drop into today’s task what was created just hours before or years before. But when it comes to duplicate shapes in NX, there are many methods, each having their own options and nuances. In Part 1 we looked at comprehensive lists of the considerations of the various methods of duplicating shapes in NX models as well as when to use them and tips for using them.

This “Part 2” installment will provide the specific steps and statistical test data of the various methods of duplicating shapes in NX models. At the end, we will compare those methods with pros and cons and summarize the report with observations that will hopefully help you to not only decide which approach is best for the various challenges you have but also develop a confidence that you’re not “leaving any money on the table” when modeling these NX parts.

A Molex electrical connector with 90 identical terminal ports

 

Review the NX11 Modeling Methods Considerations:

  • Move/Copy Object
  • Sketch – Pattern Curve
  • Pattern Feature
  • Pattern Face
  • Pattern Geometry – bodies, faces
  • Copy/Paste Face
  • Copy/Paste Feature
  • UDF

Methodology

Multiple splines in fleur-de-lis design involved higher NURBS computation and processing providing a more challenging performance scenario.

 

 

The Base Solid

Creating the base solid geometry
  • A 96″ x 48″ rectangle in a Sketch was extruded using the Connected Curves to create the base solid panel.

screen-shot-2016-11-16-at-2-38-26-pm

 

 

 

 

 

 

  • The file was saved as – extruded_sketched_rectangle.2 – and closed.
  • Total memory of the part was 93 Kb.

 

 

Move Object/Copy – Extruded Explicit Curves

Explicit Curve Fleur-de-lis, Copied with Move Object, Single Extruded Feature, Internal Subtract
  • As a simple, curve-based non-associative solid model reference, a single fleur-de-lis was created using explicit curves (splines and lines) and copied with Move Object. Than all curves were extruded along with a boundary rectangle, which internally subtracted 180 solids, 6 per fleur-de-lis.

screen-shot-2016-11-16-at-2-55-36-pm

  • Part file was saved as explicit-curves_move-object-copy_extrude_int-subtract.2 and closed.
  • Total memory of the part was 1552 Kb.

 

Explicit Curve Fleur-de-lis, Copied with Move Object, Single Extruded Feature, External Subtract
  • The single fleur-de-lis was extruded, no Subtract.
  • The 6 fleur-de-lis solid bodies were copied with Move Object to all 30 positions.
  • All 180 solids were then subtracted externally.

screen-shot-2016-11-17-at-9-17-34-am

 

 

 

Explicit Curve Fleur-de-lis, Copied with Move Object, Single Extruded Feature, External Subtract
  • 180 separate Body features and one external Subtract feature.
  • Part file was saved as explicit-curves_extrude_move-object-copy_ext-subtract.2 and closed.
  • Total memory of the part was 2124 Kb.

screen-shot-2016-11-17-at-9-25-19-am

Preparing the Profile for Duplication
  • Using the previous part with only the base solid and initial fleur-de-lis curve profile, a Sketch was created on the top face of the solid. Half of the fleur-de-lis was added, Continuous Auto Dimension on.

screen-shot-2016-11-17-at-9-30-13-am

  • All splines were then fully fixed, which eliminated all Dimensions. (Some redundant Fix constraints were deleted.)
  • Half fleur-de-lis was then mirrored inside the Sketch, fixed constraints on line end points removed, and 2 locating dimensions added.screen-shot-2016-11-17-at-9-32-42-am
  • The Sketch was not extruded yet.

  • The part file was saved as mirrored-sketch.2 for use as the first template part.
  • The total memory of this file was 169 Kb.
screen-shot-2016-11-17-at-9-40-04-am

 

 

Sketch – Pattern Curve

Pattern Curve, Extrude, External Subtract
  • The sketched fleur-de-lis was duplicated into a 6×5 layout using Pattern Curve.
  • The part file was saved for use as a template file in subsequent examples, pattern-curve.2.
  • Total memory of this file was 528 Kb.

screen-shot-2016-11-17-at-9-44-46-am

  • Entire Sketch was extruded Through All.
  • As a separate external feature, all 180 tool solids were subtracted from the base solid.
  • The part was saved as pattern-curve_ext-subtract.2prt and closed.
  • Total memory of the part was 2520 Kb.

 

screen-shot-2016-11-17-at-9-47-52-am

Pattern Curve, Extrude, Internal Subtract
  • pattern_curve.2 was reopened and all of the Pattern Curves were extruded but this time they were subtracted from the base solid internally as part of Extrude (4) feature.
  • The part was saved as pattern-curve_int-subtract.2.prt and closed.
  • Total memory of the part was 1936 Kb, a reduction of around 500 Kb.
screen-shot-2016-11-17-at-9-51-16-am

 

Internal vs External Boolean Subtract Operations

Single Extrusion Template Part, External Subtract
  • mirrored-sketch.2 was reopened and the single Sketch profile was extruded, then subtracted from the base solid as an external Boolean feature.
  • The part was saved as single-extrude_ext-subtract.2 and closed.
  • Total memory of the part was 265 Kb.

screen-shot-2016-11-17-at-9-55-22-am

Single Extrusion Template Part, Internal Subtract
  • mirrored-sketch.2 was reopened and the Sketch was extruded and subtracted internally from the base solid.
  • The part was saved as single-extrude_int-subtract.2 and closed.
  • Total memory of the part was 229 Kb, again a reduction, although very slight.screen-shot-2016-11-17-at-9-58-08-am

 

 

Pattern Feature

Pattern Feature, Simple Method
  • Immediately after the single extrusion with an internal subtract operation, Pattern Feature was used to create the 6 x 5 Linear Layout (2 Directions) of that single subtracted extrusion.
  • The Simple Pattern Method was selected and Create Reference Geometry was turned off.
  • This was very easy and very fast.screen-shot-2016-11-17-at-10-11-29-am

 

 

 

Pattern Feature, Simple Method
  • Extrude (4) and its internal Subtract were internal to the Pattern Feature Instances.
  • The part file was saved as int-subtract_pattern-feature_simple_ref-pattern-off.2 and closed.
  • Total memory of the part was 1412 Kb.

screen-shot-2016-11-17-at-10-13-14-am

Pattern Feature, Simple Method, multiple features
  • Using the single extrusion part with the external subtract, Pattern Feature was used again to create the 6 x 5 Linear Layout of that extrusion.
  • The Simple Pattern Method was selected but the Create Reference Patterns option was on.
  • An alert and a warning appeared, recommending the Simple option is generally for single features.screen-shot-2016-11-17-at-10-19-28-am
Pattern Feature, Simple Method
  • 2 Pattern Features were created, the 1st, comprised of the extruded solids, being hidden.
  • The part file was saved as ext-subtract_pattern-feature_simple_ref-pattern-on.2 and closed.
  • Total memory of the part was 2924 Kb.screen-shot-2016-11-17-at-10-21-02-am
Pattern Feature, Simple Method, multiple featuresscreen-shot-2016-11-17-at-10-26-18-am
Pattern Feature, Simple Method
  • When the above approach was repeated but with the Create Reference Patterns option turned off, another alert appeared:screen-shot-2016-11-17-at-10-24-06-am
  • 2 Pattern Features were created.
  • The part file was saved as ext-subtract_pattern-feature_simple_ref-pattern-off.2 and closed.
  • Total memory of the part was 3372 Kb.
Pattern Feature, Variational Method
  • Using the single extrusion with the external subtract operation, Pattern Feature was used again to create the same layout.
  • The Variational Pattern Method was selected; Pattern Feature Output.screen-shot-2016-11-17-at-10-28-38-am

 

  • An alert appeared:

screen-shot-2016-11-17-at-10-30-06-am

 

 

 

 

  • One Pattern Feature was created containing instances of the cutout.
  • The part file was saved as ext-subtract_pattern-feature_var_pattern-feature.2 and closed.
  • Total memory of the part was 4300 Kb.screen-shot-2016-11-17-at-10-31-28-am

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pattern Feature, Variational, Copy Features, Create New Expressions
  • Again using the single extrusion with the external subtract operation, Pattern Feature was used to create that same layout.
  • The Variational Pattern Method was selected and Copy Feature Output.
  • Expressions option of Create New selected.screen-shot-2016-11-17-at-10-34-48-am
Pattern Feature, Variational, Copy Features, Create New Expressions
  • Pairs of individual features were created, each pair with an Extrude and a Subtract feature.
  • The part file was saved as ext-subtract_pattern-feature_var_copy-features_new-expr.2 and closed.
  • Total memory of the part was 4272 Kb.screen-shot-2016-11-17-at-10-36-40-am
Using Pattern Feature, Variational Method, Copy Features into Feature Groups, Link to Original
  • Using the single extrusion with the external subtract operation, Pattern Feature was used to create the same layout.
  • The Variational Pattern Method was selected and Copy Features into Feature Groups Output.screen-shot-2016-11-17-at-10-39-12-am
  • Expressions option of Link to Original selected.

 

 

Pattern Feature, Variational, Copy Features into Feature Groups, Link to Original Expressions
  • A Feature Group named “Pattern” was created, containing Extrude and Boolean Subtract features for each duplicate cavity.
  • The part file was saved as ext-subtract_pattern-feature_var_feature-groups_linked-expr.2 and closed.
  • Total memory of the part was 4256 Kb.screen-shot-2016-11-17-at-10-41-41-am

 

 

 

 

 

 

 

 

 

 

Extrude, Ext. Subtract, Pattern Feature, Var’l Method, Copy into Feature Groups, Create New Expressions
  • Using the single extrusion with the external subtract operation, Pattern Feature was again used to create the same layout.
  • The Variational Pattern Method was selected and Copy Features into Feature Groups Output.screen-shot-2016-11-17-at-10-44-41-am
  • Expressions option of Create New selected.

 

  • A Feature Group named “Pattern” was created, containing Extrude and Boolean Subtract features for each duplicate cavity.
  • The part file was saved as ext-subtract_pattern-feature_var_feature-groups_new-expr.2 and closed.
  • Total memory of the part was 4280 Kb.screen-shot-2016-11-17-at-10-47-37-am

 

 

Other Pattern Feature Approaches
  • Several other examples were tested using Pattern Feature with the Internal Subtract source part and various combinations of Methods and options.
  • Most were fairly equal in total memory except for the Simple Method, Reference Pattern ON, 2nd lowest! The similar example covered earlier with Simple Method, Reference Pattern OFF was also fairly low in memory at 1412, tied for 3rd lowest!

 

screen-shot-2016-11-17-at-10-51-05-am

 

 

 

Pattern Face

Extruded, External Subtract, Pattern Face
  • Using the part single-extrude_ext-subtract.2 as the template, Pattern Face was used and the 20 side faces of the externally subtracted extrusion in the template part were selected.
  • The same 6 x 5 array was defined using the same input objects for Directions 1 & 2.
  • Like the earlier Pattern Feature option that used the Simple Method, this was extremely easy to create!
  • 6 total features:screen-shot-2016-11-17-at-10-57-12-am

 

 

 

 

 

  • The part file was saved as ext-subtract_pattern-face.2 and closed.
  • Total memory of the part was 1412 Kb.
Extruded, Internal Subtract, Pattern Face
  • Using the part single-extrude_int-subtract.2 as the template, Pattern Face was used and the 20 side faces of the internally subtracted extrusion in the template part were selected.
  • The same 6 x 5 array was defined using the same input objects for directions.
  • This was exactly like the previous Pattern Face example, extremely easy to create!
  • The part file was saved as int-subtract_pattern-face.2 and closed.
  • Total memory of the part was 1368 Kb. This was the lowest total memory example of all!

 

 

 

 

 

 

 

Pattern Geometry

Single Extrude, No Subtract, Pattern Geometry Using Bodies, All Subtracted
  • Initial fleur-de-lis extruded but not subtracted.
  • Then Pattern Geometry used to create 174 more solids from the previous 6.
  • All bodies subtracted in one Boolean feature.
  • The Associative option was ON and Copy Threads OFF.screen-shot-2016-11-17-at-11-05-58-am.
  • 6 total features:
  • The part file was saved as extrude-no-subtract_pattern-geometry-bodies_subtracted.2 and closed.
  • Total memory of the part was 2220 Kb.

screen-shot-2016-11-17-at-11-08-27-am

 

 

 

Extruded, External Subtract, Pattern Geometry Using Faces, Trim Body x 174
  • Initial fleur-de-lis extruded and subtracted externally. Pattern Geometry, face selection used to create sheet body instances.
  • Then Trim Body used to create additional 174 cavities in the base solid – INDIVIDUALLY.screen-shot-2016-11-17-at-11-11-00-am

 

 

 

 

 

 

 

 

 

 

 

 

  • Unfortunately, Trim Body only allows one closed set of faces to trim with – a separate Trim Body feature had to be created for each set of faces. EXTREMELY TIME CONSUMING!screen-shot-2016-11-17-at-11-12-25-am
  • The part file was saved as ext-subtract_pattern-geometry-faces_trim-body.2 and closed.
  • Surprisingly, even with 181 solid bodies and 174 Trim Body features in the part file, total memory of the part was only 3696 Kb.
Extruded, Internal Subtract, Pattern Geometry Using Faces, Trim Body x 174
  • The same approach was used but using the internally subtracted initial extrusion instead.
  • 174 Trim Body features still had to be created, like the tedious external subtract example.screen-shot-2016-11-17-at-11-15-10-am
  • The part was saved as int-subtract_pattern-geometry-faces_trim-body.2 and closed.
  • With 180 less features than the previous example, total memory was still 3552 Kb, only 144 Kb less, 36 Kb of that from template files.

 

 

 

Synchronous Copy Face

Extruded, Internal Subtract, Copy Face, Paste Copied Faces, x29
  • single-extrude_int-subtract.2 file opened.
  • [Synchronous] Copy Face used to select all 20 side faces of the first fleur-de-lis cavity using “Boss or Pocket Faces” Curve Rule.
  • With Paste Copied Faces option turned ON, the cavity is automatically copied into the base solid along with source geometry.
  • Distance option used but only one direction can be copied at a time.

 

 

 

 

 

 

 

 

 

screen-shot-2016-11-17-at-11-23-15-am
  •  Cavities created by copying and pasting one cavity set (20 faces) at a time, for reference, yielding 29 additional features in the part.
  • This was a tedious task that took longer with each instance. The process slows more and more as new Copy Face features are created.
  • Not a recommended approach, for reference only.
  • File was saved as single-extrude_int-subtract_copy-face_x29.2 and closed.
  • Total memory of the part was 2028 Kb.

 

 

 

screen-shot-2016-11-17-at-11-27-09-am
Extruded, Internal Subtract, Copy Face, Paste Copied Faces, Multiple Cavity Copy
  • A second example started exactly as the previous exercise using the same starting part file.
  • Instead of copying and pasting one cavity face set at a time, multiple sets were copied, reducing the number of steps (features) in the process.screen-shot-2016-11-17-at-11-30-04-am

 

 

 

 

 

 

 

 

  • The process slows when many faces (>50) are selected so strategic selection avoided that and also kept the feature count down to 10.
  • File was saved as single-extrude_int-subtract_copy-face.2 and closed.
  • Total memory of the part was only 1628 Kb.

screen-shot-2016-11-17-at-11-32-33-am

Extruded, External Subtract, Copy Face, Paste Copied Faces
  • single-extrude_ext-subtract.2 file with external Subtract feature opened and nearly the same process used as the internally subtracted example above.
  • With the Paste Copied Faces option turned ON, the cavities are  still automatically subtracted from the base solid because it copies faces of the Subtract feature, not the Extrude feature.

 

 

 

 

 

 

 

 

 

 

screen-shot-2016-11-17-at-11-41-13-am
  • The strategic face set selection done differently but still kept the feature count down to only 11.
  • VERY SLOW process when 300 faces were copied.
  • File was saved as single-extrude_ext-subtract_copy-face.2 and closed.
  • Total memory of the part was 1656 Kb.

 

 

 

 

 screen-shot-2016-11-17-at-11-43-15-am

 

 

 

Copy Feature/Paste

Extruded, External Subtract, Copy Feature, Paste
  • To use this approach, fleur-de-lis had to be created in a separate Sketch from the rectangle. Otherwise, the fleur-de-lis cavity and the base solid are copied/pasted due to the referencing of the parent geometry.
  • Examples above contained a sketched rectangle, so that method was used for the base solid for objectivity.screen-shot-2016-11-17-at-11-53-27-am

 

 

 

 

  • The file single-extrude_ext-subtract.2 was opened.screen-shot-2016-11-17-at-11-55-08-am
  • Fleur-de-lis Sketch, Extrude, and Subtract all duplicated using Copy Feature/Paste. However, with no new Sketch reference objects, “Inferred Resolution” causes a subtract error.
  • Choose OK, the command cancels.screen-shot-2016-11-17-at-11-56-01-am
 

  • Copy Feature/Paste has many options.

screen-shot-2016-11-17-at-11-57-22-am

  • With the Select Parents option, only the Sketch Plane (base solid face) and an Origin Point need be selected. The Datum Axis (Horizontal Ref) can be inferred.

 

  • If only the Face Reference is selected for the Sketch Plane and no Point, the Subtract fails because it has no solid geometry to remove at the location of the parent geometry.screen-shot-2016-11-17-at-11-59-57-am
  • However, the 3 features do get copied.
    screen-shot-2016-11-17-at-12-01-01-pm
Extruded, Internal Subtract, Copy Feature, Paste
  • If so, the curves in the Sketch can be repositioned with the NX9 Move Curve Sketch command; even splines with Fix constraints.screen-shot-2016-11-17-at-12-06-46-pm
  • Sketch Dimensions locating the curves will update to the new values automatically.
Extruded, External Subtract, Copy Feature, Paste
  • Instead of using Move Curve, 29 new Origin Points were created at equivalent fleur-de-lis origins.
  • Then Copy Feature/Paste was used by simply selecting: the Face reference in the list, the base solid top face, the Point reference, the next Point in the layout, and Apply. Face reference, face, Point reference, point, Apply, repeat. Pretty fast!screen-shot-2016-11-17-at-12-11-06-pm
  • Instead of copying and pasting one cavity feature set at a time, you can copy multiple sets and speed up the process greatly.screen-shot-2016-11-17-at-12-12-45-pm
  • For each cavity, there is a Sketch and Extrude feature.screen-shot-2016-11-17-at-12-13-41-pm
  • The part file was saved as ext-subtract_copy-feature-paste.2 and closed.
  • Total memory of the part was 5272 Kb. For all that work, the result isn’t worth the effort. But this approach offers other benefits. See below.
Extruded, Internal Subtract, Copy Feature, Paste
  • Repeating this process on the single, internally subtracted fleur-de-lis part file was exactly the same except that it went much faster since all the Subtract features were inside the Extrude features.
  • The part file was saved as int-subtract_copy-feature-paste.2 and closed.
  • Total memory of the part was 3772 Kb, a reduction 1500 Kb! But still a fairly large amount, relatively speaking.

 

 

User Defined Feature (UDF)

Building the UDF Tool
  • The fleur-de-lis Sketch of one of the previous parts was copied into a new file named udf-tool_cutout.2. The rectangle of the part perimeter was omitted.
  • A Primitive Block, slightly bigger than the Sketch, was created and reordered before the Sketch.
  • The Sketch was associatively reattached to the Block for Placement Face, Horizontal Reference, and Origin Point. Sketch Dimensions were recreated to associatively locate the fleur-de-lis relative to the Block.
  • Then the fleur-de-lis curves were extruded upward and all were united into one solid body. This would serve as the UDF tool to be subtracted from the panel to create cutouts.screen-shot-2016-11-17-at-12-22-43-pm
  • When inserted, only the solids of the fleur-de-lis would subtract from the target part.
  • udf-tool_cutout.2 was saved and closed.
  • For reference, total memory of the part was 251 Kb.
Defining the UDF Tool
  • Using the Wizard, a UDF was defined comprised of only the Block, Sketch, and Extrude features. The CSYS and Datum CSYS Origin Point were added as Additional References to aid in locating the UDF.screen-shot-2016-11-17-at-12-24-52-pm

screen-shot-2016-11-17-at-12-27-36-pm

  • The UDF definition was named udf-tool_cutout.
Inserting the UDF Tool
  • The template part extruded_sketched_rectangle.2 was opened but before any UDF’s were added, 29 more Datum CSYS’s were added for all origin positions.

screen-shot-2016-11-17-at-12-32-46-pm

  • The UDF udf-tool_cutout was inserted very quickly by selecting the first point, the CSYS, and choosing Apply.
 screen-shot-2016-11-17-at-12-34-17-pm
  • This was repeated for the other 29 positions.
  • All UDF’s were subtracted from the panel externally as a single Subtract feature.
  • The part file was saved as udf_ext-subtract_inserted_x30.2 and closed.
  • Total memory of the part was 4208 Kb.

screen-shot-2016-11-17-at-12-36-42-pm

Building the UDF Tool with an Internal Subtract
  • The tool file, udf-tool_cutout, was reopened.
  • A 96” x 48” x .1” Block was added to the top corner of the UDF screen-shot-2016-11-17-at-12-40-35-pmtool just above the Datum CSYS and the UDF tool was subtracted from that Block.

 

 

 

  • screen-shot-2016-11-17-at-12-43-04-pmThen UDF_fleur-de-lis_int-subtract was created with the Subtract feature added.

 

 

 

 

 

Inserting the UDF Tool with an Internal Subtract
  • extruded_sketched_rectangle.2 was opened and Pattern Geometry, using the Point filter option, was used to duplicate that Origin Point to the other 29 positions on the panel.screen-shot-2016-11-17-at-12-45-43-pm
  • The new UDF, UDF_fleur-de-lis_int-subtract, was inserted and the panel was only selected once as the “Target for the Subtract”.
  • The first UDF needed the Base Point and the Target Solid selected but the rest were all inserted very quickly by selecting only the next Point and choosing Apply (CTL-MB2).screen-shot-2016-11-17-at-12-47-20-pm
  • This was repeated for the other 29 positions.
  • The part file was saved as udf-int-subtract_inserted_x30.2 and closed.
  • Total memory of the part was 3844 Kb.screen-shot-2016-11-17-at-12-48-34-pm

 

Pros and Cons

Pros

Move/Copy Object(s)
  • Simple in concept
  • Duplicates all object types, not features
  • Copies any number of objects
  • Lots of motion options
  • Can duplicate in 3D directions
  • Can create “instances” at divisional increments

Cons

  • Non-associative
  • Not intended to support parent/child relationships
  • Copies only in one direction or motion
  • Later design changes can be cumbersome, laborious
  • Booleans must be added separately after copying
  • Performance usually slowed due to bulk of object data instead of face representation

 

Sketch – Pattern Curve
  • Good for creating unique feature profiles that utilize pattern geometry (like gear teeth, etc…)
  • Option to create Pattern expressions
  • Fairly low memory when used with internal Booleans
  • Can create dimensions to locate instances
  • Keeps feature tree short
 

  • Only 3 Layouts available (must be 2D)
  • No “pattern” definition created inside Sketch
  • If used to create a multi-body feature – Limited to simple features – Have to add detail features (blends, etc…) to each instance
Pattern Feature
  • Many layout options: along path, circular, within/out boundary, staggered, spiral
  • Multiple features can be duplicated all at once including Booleans, trims, blends, draft, Sketches, etc.
  • Lots of modifier options: Variational, Follow Face, Output Settings, Patterns of Patterns, Create Reference Geometry, etc.
  • Each instance evaluated fully allowing individual parameter edits, alignment
  • Can suppress any instance
  • Fast and easy creation
  • Simple Method has low memory and fast updates
  • Performance (Each instance of the pattern is fully evaluated)
  • Edit-ability can be limited when using “copy” Output Setting in Variational
  • Some settings create results where Pattern Method cannot be changed
  • Many options cause many decisions, can be confusing

 

 

Pattern Face
  • Similar layout options as Pattern Feature
  • Can include Booleans, trims, or patches of parents
  • Single feature
  • Easy to create
  • Lowest memory of all examples
  • Fastest update performance
  • Reduces number of features
  • Topology limitations: “Geometry needed cannot accommodate the change”
  • Instances cannot be unique

 

 

 

Pattern Geometry
  • Duplicates objects, not just features
  • Creates a single feature – reduces number of features
  • Many, many options
  • Can be associative
  • Can duplicate in multiple ways (2 Linear Layout directions, Circular Layout concentric members, etc.)
  • Can copy threads
  • Patterns of Patterns
  • Limited scope – afterwards faces must be sewn or used from trimming, Booleans done individually
  • When creating many objects, higher memory
  • Can be very time consuming when copying trimming or patching faces
  • Slower performance – using faces doubled update times

 

 

Synchronous Copy Face
  • Can copy more than 1 face
  • An “all-in-one-step” method
  • Can keep memory low
  • Can apply parent Boolean, trim, or patch operations
  • Repeatedly paste from clipboard rapidly
  • Best for non-repetitive, irregular intervals/positions
 

 

  • Does not create editable expressions
  • Later position edits require awkward Move Object processes
  • Creates lots of features
  • Can only paste in one direction at a time
  • Can be very tedious
  • Can be very slow
Copy Feature/Paste
  • A two step process
  • Can copy/paste multiple features
  • Can paste geometry into other part files
  • Paste Special creates new objects, many options for position
  • Expression mapping
  • Requires referencing objects (Placement Face, Origin “Point, etc.) before pasting
  • Update times nearly 2x when using external Booleans
  • Slower performance and higher memory
User Defined Feature (UDF)
  • Can add any number of features Infinitely variable applications
  • Reusable – any part, any user
  • Supported by Reuse Library – can drag & drop
  • Performance with external Boolean actually very fast
  • Features defined into UDF get “hidden” unless expressions or reference objects specifically added
  • Memory higher than most

 

 

Statistical Reports

Tabulation of Results: Total Memory and Preformance

 

 

screen-shot-2016-12-05-at-10-17-21-am

 

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screen-shot-2016-12-05-at-10-19-15-am

 

screen-shot-2016-12-05-at-10-19-45-am

 

screen-shot-2016-12-05-at-10-20-19-am

 

screen-shot-2016-12-05-at-10-20-55-am

 

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Summary

When modeling parts with duplicate shapes:
  • Plan out how to construct the duplicate shapes.
    • Get a good ROI for your time and modeling intensity during creation.
    • Identify the magnitude and frequency of potential model changes – duplicate with appropriate method(s) accordingly.
    • Consider using a combination of patterning techniques.
    • Performance is based on more than just model structure and # of features.
    • Make sure the chosen method captures the intent of the duplication.
  • Primarily, use Sketch Pattern Curves to create duplicate feature profiles.
  • Limit multi-body features (generally created from Sketch Pattern Curves).
  • When possible, with Pattern Feature, use Simple method and limit to small patterns.
  • Pattern Face is more efficient. Use it as alternative to Pattern Feature.
  • Use Instance Geometry to pattern base solids of duplicate shapes.
  • Instance Geometry with Pattern Features or Pattern Faces can provide even better performance.
  • Create Booleans internally to the solid feature to reduce memory.
  • Consider UDF’s for shapes that will universally be added to models with variations of size, location, inclusion of details (blends, chamfers, etc.).

So those are the more rational options to duplicate existing geometry in NX11. There are still other possibilities but none that we would suggest using without some additional enhancement such as contained within a script, NX Open routine, or other programming option and certainly not without specific standard procedures in place.

We hope this study helped to clarify the various options at your disposal for duplicating shapes in NX models. Some methods aren’t very good for some tasks and other methods may improve your models tremendously. Thanks for your attention (and patience!) and good luck!

 

 


garrett_150Garrett Koch | PLM Application Engineer, Swoosh Technologies

Well-accomplished in drafting, design, and engineering in many industries since 1973, Garrett has been developing patentable designs and has taken on large-scale engineering projects. In 1994, he embarked on a different career in CAD training, courseware development, and technical support – where he focused on teaching a variety of students (including PhD’s from MIT, project engineers at Los Alamos National Labs, officers at NASA, and users across the continent at major manufacturers of aerospace, automotive, and power generation). Garrett excels at the knowledge transfer of NX mechanical CAD and Teamcenter and is considered an expert in NX installation, configuration, and technical support.

Want to learn more about NX? Contact us at 314-549-8110 or use the contact form to get in touch!

 

 

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