Frequently Asked Questions
Batch Processing in Non-GUI Mode
Question: Can I run a batch process without using the CADfix interface?
Answer: Yes. Click here (PDF) for batch processing instructions relevant to CADfix V7.1.
CATIA Files
Question: Is there a CATIA V4 file extension that CADfix handles better that others. For example, 2 different
extensions CATIA has are .model and .dlv3. Is there a difference as far as using CADfix is concerned? Is one more reliable than the other?
Answer: Here is the order of preference:
- .model and .exp files are the preferred format.
- .exp format files can contain multiple .model files, but the user can choose which one to import.
- .dlv3 files are the least preferred.
Connectivity
Question: Are there specific geometry problems (such as duplicates or T-junction intersections) related to various levels of connectivity? For example, what kind of geometry problem should I look for with a connectivity of 1 or 3 or more?
Answer: The significance of the connectivity number depends on the type of model, i.e., is it a open shell model or a solid model? If the model is a open shell only, then a connectivity of 1 = a free edge (connected to one face) or maybe a valid hole in the model. A connectivity of 3 for a shell model maybe some form of valid fabrication junction. A connectivity of 1 for solid models means either there is extra edges superfluous to the model or there is some topology hole, i.e. face missing. A connectivity of 3 or more indicates extra connections or overlapping geometry which will need some manual intervention to remove.
Question: I have become pretty good at eliminating edge-face connectivity of 0 and 1. However, I can't seem to do anything about connectivities above 2. How do I approach these?
Answer: Connectivity higher than 2 in solid models generally are bad and need to be manually removed. This can have several causes:
- Duplicate faces - cure this by merging surfaces and then faces (can only be a duplicate face if two or more faces share the same edges and a common underlying surface).
- Overlapping faces - there is no easy cure for this in CADfix and in some situations you have to remove one or more faces and rebuild them from the edges that are left. The new faces you build can then be made so as not to overlap. Alternatively you may be able to use the �Create/edit faces� tool to redefine the faces to correct the connectivity problem by using the existing edges.
- Partially collapsed faces - this is normally fixed with the Integrity tools which usually involve splitting the face.
- Non-manifold solids - sometimes the high connectivity is OK as it is a consequence of a non-manifold solid geometry. You'll need to examine with the Probe tool to see whether it is a problem or not.
- The Probe tool is normally the most useful starting point for edges of high connectivity, as it allows you to familiarise yourself with the topology, isolate the problems by examining what faces are connected.
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Discontinuity
Question: What can you tell me about discontinuous NURBS?
Answer: Click here(PDF) for information on discontinuous NURBS.
Entity Types
Question: Can you tell me what IGES entity types are supported by CADfix 5.0 import and export?
Answer (in PDF format):
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Export
Question: When should I use Prepare for Export?
Answer: We suggest that you always pass the model through Prepare for Export. However with some experience it is possible to recognize models that do not need any further processing before export. In the case where models come in very cleanly, e.g., some ProENGINEER IGES files which create a body on import, it is quite often possible to Wizard -> Import and Repair -> Complexity dekink edges and faces then go straight for export. It is very much a trial and error process to get to this judgment point
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File Formats
Question: What file formats does CADfix support?
Answer: Please look at the Availability Matrix for Each CADfix Release.
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IGES NURBS
Question: Can CADfix convert IGES NURBS to analytical geometry and export to Parasolid?
Answer: Yes
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CADDS License
Question: Does CADfix CADDS import/export requires a runtime or full development license?
Answer: You should only need a runtime license to use CVDORS. Ask the PTC supplier for the Runtime licence 0536 feature. You should check very carefully with your supplier that you do not already have the CVDORS runtime license feature because it comes in many guises. You may have it and not know it.
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Multiple Bodies
Question: For models with multiple bodies, what happens if 2 bodies share an edge (or is this possible)?
Answer: For models with multiple bodies, it is quite possible for edges and faces to be shared. To allow each body to use independent edges, use the Unshare option in the Topology tools. You access the Topology tools under the Diagnostics tab.
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Platforms
Question: What are the supported platform configurations for CADfix?
Answer: Click here for the platform configurations.
Question: There are occasions when I go to install CADfix, start the installation from CD, and I'll see a message that says "There are no supported platforms in the current working directory". Why does this happen?
Answer: This usually happens when you see the contents of the CD in uppercase characters. To overcome this problem, you can create a symbolic link to the installation.
Creating a symbolic link to install CADfix:
- Create a directory where you want to install CADfix.
- Create a symbolic link to the installation from within the directory
%ln -s /CDROM/UNIX/FEGSINST.SH fegsinst.sh
(where % = the UNIX system prompt)
- You should also create links to the .tz files on the CD, for example:
ln -s /CDROM/UNIX/SGI.TZ sgi.tz
- Then, start the installation from within the directory
%./fegsinst.sh
- The installation will start, and you can proceed.
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Pan with 2-Button Mouse
Question: When using a two-button mouse, how do you pan?
Answer: Hold down both buttons.
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Split body with a plane
Question: What is the purpose of the "Split body with a plane" function?
Answer: This is used if you are going to downstream analysis applications where general topology models are not meshable by the CAE system you are exporting to. This is not normally required for basic CAD to CAD transfer.
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Probe Tool
Question: When using the Probe tool, some edges of a face may be preceded with a + or - sign. Why?
Answer: The + or - sign by the parts tabulated in the Probe tool indicate the orientation of the parts with respect to the embedded geometry, i.e., in the case of edges, a + means that the start and end point create a vector direction that is in sync with that of the underlying surface.
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Set Manager
Question: If CADfix reports that there are faces in a model with only 2 edges, how can I locate them?
Answer: Use of the Set Manager should allow you (through the filters) to select faces with two or more edges.
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Shaded Display
Question: Why can't you see the shaded display of faces when you first read in some files?
Answer: If the model is not fixed to good connectivity with valid faces, they cannot be shaded. The shading requires faces that are correctly defined and have valid topology.
Question: When shading faces, why are some faces are not shaded, even though they are actually valid faces?
Answer: The faceting algorithm we use has some limitations and cannot shade a face where there is a very small edge relative to the rest (otherwise, the algorithm could go on forever). If you zoom in very close, you can see the short edges that cause the problem. If you merge points at a tolerance to remove these short edges, then the faces can be shaded. It is the same on Unix and NT. You can also toggle the 'Faceting limited by short edges' setting which can be accessed from the pull down menu - View...Display Settings.
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Wizard
Question: When using the Wizard during healing, does the Wizard fix the edges and move the surface or vice-versa?
Answer: The Wizard does SMART healing, where it first tries to re-intersect surfaces and move edges to the new intersections, and then for the sloppy geometry remaining it will adjust the surfaces.
Question: Wizard Prepare for STEP-to-Pro/E has been modified to stop surface extensions and surface de-kinking. If I run the part through a Diagnostic check, and the diagnostic reports shows that some surfaces need extending, should I ignore them, and if so, why or why not?
Answer: The diagnostic tool is NOT supposed to scan for extending surfaces when the export system is STEP-for-ProE. You should ignore the diagnostic findings for this test. The de-kinking test should have been ignored.
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