SolidWorks 2011 Parts Bible - Matt Lombard [299]
Next, open the Parasolid file called bad face.x_t. This one also imports without an error or warning on the Import feature, but there is clearly a missing face. It is easier to visualize the separate faces of the part if you change the display mode to Shaded With Edges. If you examine the part closely, you can see that several faces are not lined up square with the rest of the part. Notice also that there are small sliver faces. This may be intentional, or it may be part of the problem. Triangular faces and sliver faces (with very sharp corners, usually long and narrow) are often the source of errors in translated parts.
FIGURE 23.6
Clean imports from Parasolid have the tendency to be fast and trouble-free.
Right-click the Import feature and run the Import Diagnosis; you will see the faulty face listed. Click the Attempt to Heal All button to fix the faulty face. Figure 23.7 shows the part with the faulty face.
FIGURE 23.7
Three-sided and sliver faces are often the source of errors with imported parts.
Now open the Pro/ENGINEER file called bad face 2.prt.29. Pro/ENGINEER files often end with version numbers as the extension of the file. You need to be careful if you see a file that looks like a Pro/ENGINEER file with no version extension. SolidWorks used the *.prt extension for the first couple of years and still opens this type of file as a native file. You may still find some of those parts in circulation.
Open the file using the Import Geometry Directly option, and switch the display to Shaded With Edges, and run an Import Diagnosis. The part has a bad face. If you click on the face in the Faulty Faces list, you can see that the face is next to a small, pointy triangular face, shown in Figure 23.8. The Attempt to Heal All option takes care of it.
FIGURE 23.8
Importing the same data in different ways can give you different results.
Import the same file, but this time choose the Analyze the Model Completely option. It should tell you that it recognizes 13 out of 13 features. Click the Features button and watch the part rebuild. Notice that this time the part comes up with a feature error. The error is on a fillet. It is not an accident that the previous error was on a face next to a fillet face.
Notice that the Parasolid parts came up almost immediately, but the Pro/ENGINEER parts take several seconds to process the data. As the imported files become larger and larger and branch into assemblies, this difference becomes more and more pronounced.
Next is a sheet metal part. Open sheet metal.x_t. Change the display to Shaded With Edges. The part looks good, and Import Diagnosis says that it is okay. Because this is a sheet metal part, and it appears to have a consistent thickness, you will try to flatten it. Click the Sheet Metal CommandManager tab, and click the Insert Bends icon (on the far right side). Select the big flat face as the face to remain stationary (the top selection box), and click the green check mark button to accept the result.
The sheet metal features are added to the part, but notice in Figure 23.9 that they have failed. A close inspection of the part reveals that there is a small ledge between the big flat face and the inside bend on both ends. This was probably a modeling error rather than a translation error. You might be able to fix this to make it usable as a sheet metal part, but for imported geometry editing, you'll need to go to the end of this chapter. Here I cover the results of attempting to repair this model.
The last part I want to show in this “watch over the shoulder” demonstration is a part that I consider to be a complete loss. This is an IGES file that came from an Autodesk Mechanical product. In the DVD, open the file called valve body.igs. This part takes several seconds to import. When it does import, it has 11 surface bodies, 2 of those with errors, and some obvious problems with a couple of faces that somehow became out of control. This