Part VII: Working with Specialized Functionality
Undercut Detection
The Undercut Detection tool is in the View menu (relocated from the Tools menu) or on the
Evaluate tab of the CommandManager. It is also an on or off display tool, which changes dynami-
cally 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. 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:l Direction 1 Undercut. Should read Pull from Direction 2l (^) Direction 2 Undercut. Should read Pull from Direction 1
l Straddle Undercut. Should read Straddle faces
l (^) No Undercut. Should read No draft in the primary draft direction, but may be occluded
undercut faces
l (^) Occluded Undercut. Should read Occluded Undercut faces that have draft in the com-
pletely irrelevant primary draft directions; does not include occluded undercut faces that
have no draft in the primary direction
Figure 32.19 shows the PropertyManager for this function and the results. If you would like to test
it for yourself, the part is on the CD-ROM with the filename Chapter 32 Draft Analysis.
sldprt.
FIGURE 32.19
The results of the Undercut Detection tool