SolidWorks 2011 Parts Bible - Matt Lombard [321]
This feature can generate a report, which to some extent answers questions about how or why it classifies faces in the way it does. To get a complete picture of the situation, it may be useful to look at the report when you are using the results to make design or manufacturing decisions. A sample of the report is shown in Figure 24.26.
FIGURE 24.26
A sample of a Thickness Analysis report
Understanding the Thickness Analysis workflow
The workflow for the Thickness Analysis tool is as follows:
1. Open a thin-walled part with some variations in thickness.
2. Start the Thickness Analysis tool by selecting Tools⇒Thickness Analysis or by clicking the icon on the Evaluate tab of the CommandManager.
3. Select the thin or thick regions option, depending on what you are most concerned about.
4. For a thin region analysis, enter in the lowest acceptable thickness. For a thick region analysis, enter in the low and the high acceptable thickness values.
5. (Optional) Select individual faces for local analysis in the Performance/Accuracy panel. This also gives you the option to get a more accurate display. The default is the least accurate option. Accuracy comes at the cost of longer analysis time.
6. Click Calculate. This calculation may take a few seconds or longer, depending on the complexity of your part. It is not an instantaneous display.
7. Observe the color gradient on the faces. Blue indicates that the wall is too thin, and red indicates that it is too thick.
Undercut Detection
The Undercut Detection tool is in the View⇒Display menu and on the Evaluate tab of the CommandManager. It is also an on or off display tool, which changes dynamically as you change the model. Undercut Detection is conceptually flawed in that it gives incorrect results every time. However, if you think of the labels as being changed slightly, the results become partially usable.
Even if you and your mold builder know that a part has absolutely no undercuts, the Undercut Detection tool will nonetheless always identify all the faces to be undercut. In fact, the only faces that this tool will identify as not undercut are faces that have no draft on them (even if they are in fact undercut). The only time it correctly identifies an undercut is when it classifies the undercut as Occluded Undercut. Faces that have no draft and are occluded undercut are improperly identified as simply No Undercut.
You may want to avoid this tool because too much interpretation of incorrect results is necessary; however, if you still want to use it, here is a translation guide that may help:
• Direction 1 Undercut. Should read Pull from Direction 2
• Direction 2 Undercut. Should read Pull from Direction 1
• Straddle Undercut. Should read Straddle faces
• No Undercut. Should read No draft in the primary draft direction, but may be occluded undercut faces
• Occluded Undercut. Should read Occluded Undercut faces that have draft in the completely irrelevant primary draft directions; does not include occluded undercut faces that have no draft in the primary direction
Figure 24.27 shows the PropertyManager for this function and the results. If you would like to test it for yourself, the part is on the DVD with the filename Chapter 24 Draft Analysis.sldprt.
FIGURE 24.27
The results of the Undercut Detection tool
Understanding the Undercut Detection workflow
The workflow for the Undercut Detection tool is as follows:
1. Open a plastic part model in which you want to find undercuts.
2. Open the Undercut Detection tool from View⇒Display or using the icon on the Evaluate tab of the CommandManager.
3. Select an axis, flat face, or plane to establish the direction of pull of the mold.
4. Interpret the results using the suggested labels listed earlier.
5. If you want to keep the colored display, click the green check icon. If you want the model to display with the normal model colors, click the red X icon. If you chose the green check icon but want to turn off