What is the difference between a surface feature and a datum plane?
Why are surface features uneffected by cuts?
When is the QUILT SURF menu available?
What is the difference between Intersect and Join?
What would cause a surface merge to not be created?
Which edges should be selected when extending a surface?
What is the difference between the Capped Ends and Open Ends options available when creating surfaces?
What is the difference between the Join and No Join options available when creating swept surfaces?
How can more control be exerted over a surface created from Boundaries?
How can a surface be created by importing point data?
What is the difference between creating a From File surface as pointwise or as arclength?
When copying a surface, how can cuts or holes be patched in?
What may prevent an open loop from being filled in when copying a surface?
Why does a quilt used for a "tweak replace", surface trim, or use quilt feature, disappear?
What may prevent a "tweak patch" feature from being created?
What may prevent a solid "use quilt" feature from being created?
What may prevent a thin "use quilt" feature from being created?
A surface quilt is a "patchwork" of connected surfaces. A quilt may contain one or more surface patches. The external edges of a surface are yellow, and the internal boundaries of the patches are displayed in magenta.
*What is a merge?
A surface merge allows multiple surfaces to be combined into a single quilt. Surface merges are created by selecting Feature, Create, Surface, Merge, and then selecting the two quilts to be combined through Intersect or Join.
Completion of the merge operation will be visually evident by turning the yellow edges to magenta.
*What is a transform?
A transform feature enables quilts and/or datum curves to be translated, rotated, or mirrored. The original feature can be repositioned and manipulated by selecting No Copy from the OPTIONS menu. A copy of the feature can be created and modified totally independent of the original by selecting Copy from the OPTIONS menu. This functionality is accessed through Feature, Create, Surface, Transform.
*What is a trim?
A trim feature removes portions of a surface feature. It is analogous to a cut or a slot for solid material.
Note, that some surface trim functionality such as Trim, Silhouette is exclusive to Pro/SURFACE.
This option is accessed through Feature, Create, Surface, Trim.
*What is an extend?
C2 continuity insures that the second derivatives of two surfaces will equal each other at their boundary. This is used when creating a new surface and defining it to be tangent to an existing surface. C2 continuity will force the curvature of both surfaces to match at their shared boundary. For example, if one surface is concave with a certain curvature value at its boundary, the new surface will not only have to have the same slope at that boundary, but must also be concave with the exact same rate of change of slope as the first surface. To apply this to a boundary, select C2 Cont from the TAN COND menu.
*What is a "tweak patch"?
A tweak patch allows one or more solid surfaces to be replaced with a surface feature. The external (yellow) edges of the surface feature must all lie on the solid geometry. Tweak patch features can both add and remove solid material at the same time. This feature type is utilized through Feature, Create, Tweak, Patch.
*What is a "tweak replace"?
A tweak replace allows a single solid surface to be replaced with a datum plane or surface feature. Tweak replace features can both add and remove solid material at the same time.
Note, if a surface feature is to be referenced for the replace, then it should extend beyond the solid.
This feature type is accessed by selecting Feature, Create, Tweak, Replace.
*What is a "use quilt" feature?
A feature created as Use Quilt, from the SOLID OPTS menu, allows material to be added or removed, depending on whether the feature is a protrusion, cut or slot. The volume of material must be completely enclosed with one continuous surface quilt if Solid is chosen from the SOLID OPTS menu. Otherwise a Thin feature can be created.
*What are blend control points?
Blend control points are either datum points or vertices of datum curves used to create a boundary blended surface. If corresponding sets of blend control points are placed on the boundary curves, they can be connected point-by-point and the curve segments between them will be blended piece-by-piece.
Refer to Creating a Surface From Boundaries Using Blend Control Points and Optional Tangency.
*What is a composite datum curve?
Composite datum curves are created by referencing several datum curves or model edges that form one continuous chain. The resulting curve is a new feature that lies on top of the referenced geometry. It is an Exact copy of the references. Note that an Approximate composite datum curve will create an approximate chain of entities with a curvature-continuous spline. Composite datum curves are created through Feature, Create, Datum, Curve, Composite, Done. The references for this feature can be selected in various ways. The options in the CHAIN TYPE menu are : One By One, Tangent Chain, Curve Chain, Bndry Chain, and Surf Chain.
Split datum curves are similar to composite datum curves. Split datum curves are copies of other datum curves that terminate at a specified surface, datum point, or datum plane that intersects or lies on the original curve. This curve type is created by selecting Feature, Create, Datum, Curve, Split, Done.
One-sided edges are the outer edges of surface features and are displayed in yellow. Yellow edges indicate where two surface features may not be merged. Internal edges, where two surface quilts may be joined, are displayed in magenta.
A surface patch is an individual surface that alone, or combined with more surfaces, makes up a quilt.
A surface feature has finite boundaries and a defined area. A datum plane is a planar reference with infinite boundaries and therefore, no defined area.
*Why are surface features uneffected by cuts?
Cuts created through Feature, Create, (Solid), Cut will only remove solid material. In order to remove a portion of a surface feature, select Trim from the QUILT SURF menu.
*When is the QUILT SURF menu available?
The QUILT SURF menu is available only if a surface feature exists on a model. Before one exists, selecting Feature, Create, Surface will default to the SRF OPTS menu.
The QUILT SURF menu will allow access to surface feature operations through New, Merge, Trim, Extend, Transform, Draft, and Area Offset.
*What is the difference between Intersect and Join, from the SURF MERGE menu?
Intersect and Join are the two methods which combine surfaces into one quilt. Selecting Intersect from the SURF MERGE menu will merge two intersecting quilts. This should be used when quilts overlap one another. Pro/ENGINEER will prompt the user to choose which portion of the selected quilts are to be remain in the final merge feature. Join will merge two adjacent quilts into one. A single-sided edge of one of the quilts must lie on the other surface. If a portion of one surface extends beyond the boundaries of the other surface, Pro/ENGINEER will prompt the user to select a portion of that surface to keep for the final merge feature.
*What is the difference between selecting a surface as Single or Whole when creating an Intr. Surfs datum curve?
Single should be used when selecting a face of a part, or a bounded patch of a surface quilt. Several surfaces can be selected at once with this option. Use Whole to select all faces of the part, or an entire surface quilt.
*Which quilt is referenced when arrows display for the portions of surfaces to be kept in a merge by intersection?
When merging quilts through Intersect, and in some cases through Join, portions of a surface must be discarded. Arrows appear at this time referencing the surface that is highlighted in cyan.
*What would cause a surface merge to not be created?
Pro/ENGINEER will be unable to create a surface merge if the selected quilts do not actually intersect. Verify that the surfaces intersect by creating a datum curve by Intr. Surfs. If the datum curve cannot be created, or is discontinuous, the surfaces must be redefined. They can be enlarged by selecting Extend from the QUILT SURFS menu.
*Which edges should be selected when extending a surface?
When creating a surface feature with Extend, from the QUILT SURF menu, select the edge(s) that is to be "stretched". Then select vertices of that edge to specify an offset distance.
*What is the difference between the Capped Ends and Open Ends options available when creating surfaces?
Surface features created with Extrude, Revolve, Blend, or Sweep can be open or closed volumes. If the surface is going to be open, select Open Ends from the ATTRIBUTES menu. If the feature is required to enclose a volume, select Capped Ends. A tube can be created by extruding a circular section as Open Ends. A closed cylinder would be created by extruding the same section as Capped Ends.
*What is the difference between the Join and No Join options available when creating swept surfaces?
Surface features created with Sweep, Var Sec Swp, or Swept Blend, by selecting edges of a surface as a trajectory, will have the option to be merged with the existing quilt. If Join is selected from the SRFS JOIN menu, the feature will be automatically combined into one quilt with the original surface. This functionality saves the step of creating a new feature with Merge. No Join simply means that the feature is not to be merged with the quilt referenced for the trajectory.
*How can the display of a surface feature be turned off?
Surface features can be removed from the model display in two ways. The first is to Suppress the feature from the FEAT menu. Suppressing a feature is like removing it from regeneration temporarily. It can be unsuppressed through the Resume menu selection. If a feature is suppressed, any features that reference this will also need to be suppressed, or redefined and/or rerouted. This method of removing a feature from the display is not always the most appropriate. A better method, which will still regenerate the feature and not effect any children, is to place the surface on a layer and blank that layer. This will just "turn off" the feature's display. Layer functionality can be accessed by selecting Layer from the PART menu. Note that the config.pro setting SHADE_SURF_FEAT may be set to Yes/No to affect the display of a surface feature.
The use of blend control points can provide additional control over the topology of surface features created from Boundaries. Control point functionality can be used to eliminate small patches and extra edges, leading to a smoother surface free from twisted and stretched contours.
Refer to Creating a Surface From Boundaries Using Blend Control Points and Optional Tangency.
*What does it mean when an offset surface feature fails, giving the message "Highlighted geometry is invalid"
The radius of curvature of the surface may be too small in some areas to be offset by the specified value. As an alternative technique, create a new surface that excludes the patches of the surface that are too curved. Offset this new surface and trim away overlapping areas. Surfaces can then be created from the boundaries of the offset quilt.
*How can a surface be created by importing point data?
A surface can be created by importing point data by selecting From File from the ADV SURF OPT menu. This will prompt for a coordinate system and then for a file name. The file must be in an imported blend format, ".ibl". A sample file can be found in the Part Modeling User's Guide. Datum curves can also be created from point data in an analogous method.
*What is the difference between creating a From File surface as Pointwise or as Arclength?
A pointwise surface will connect the first point in one curve to the first point in the other curve, the second to the second, and so on. An arclength surface will divide the curves into equal length segments and blend between them.
*When creating a surface from Boundaries, a message says that the boundary curves do not form a closed loop. Why?
The Geom Check menu pick should be available when prompted : "Boundary curves do not form a closed loop". Selecting this from the INFO menu will highlight the endpoints of the curves where the loop is not closed with green circles. There are two possible explanations for this occurrence:
2. The curves do not fully define the area for the surface to encompass. This is caused by selecting closed loop curves in one direction and open loop curves in the second direction. Break the closed loop curves into open loop segments, using split and composite datum curves. These open loop segments, in addition to the open loop curves in the other direction, will form the closed loop necessary for the boundary blend. Note, these "split" curves can also be achieved by using the selection by Chain in combination with the Trim/Extend functionality at the time of surface creation.
The surface used as reference for any of these features will be "consumed" during their creation. If the quilt is needed for later use, a copy of the quilt can be created by selecting Feature, Create, Surface, Copy.
*What may prevent a tweak patch feature from being created?
Discontinuities in surface quilts may prevent feature creation when using Feature, Create, Tweak, Patch. Verify that all of the surfaces used for the patch have been merged together into one continuous quilt. The major requirement for patch features is that all of the quilt's external edges (displayed in yellow) must lie directly on the solid model. To verify this create datum curves at the intersection of the surface features and the solid geometry.
*What may prevent a solid use quilt feature from being created?
Features being created with the Use Quilt and Solid options from the SOLID OPTS menu, must reference a quilt that completely encloses a volume to be added or removed. Any gaps, represented by yellow edges, can hinder feature creation. Surfaces that have been successfully joined have magenta edges at their borders. Any patches that are not continuous need to be joined with the Merge command.
*What may prevent a thin use quilt feature from being created?
Features being created with the Use Quilt and Thin options, from the SOLID OPTS menu, offset a selected quilt a user-defined distance and fill in that gap with solid material. The offset distance and curvature of the selected quilt are the factors which determine creation. Ensure that the chosen quilt can be offset to at least the thickness value. This can be verified by creating a surface through Feature, Create, New, Offset, and entering the thickness. It can also be investigated through the INFO menu by selecting Info, Srf Analysis, Min Radius, and selecting the surface. The info tool will find the minimum radius of the quilt, which should equal the maximum offset distance in the indicated direction.
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