Sketchers Lock and Exclude
Along with all the laughable and ridiculous changes implemented with the newest Sketcher, there are
a few really cool bits as well. For this tip-of-the-month we'll look at the tools for locking and excluding
sketcher constraints while sketching, and the sketcher dimension lock.
A quick trick for sketching is the exclusion of sketcher constraints while sketching. This is done with the
right mouse button. The example in Figure 1 is sketching lines, but it also works with other geometry.
Simply start sketching, then when a potential sketcher constraint is highlighted red (meaning sketcher is going to
assume that constraint) simply hit the right mouse button.
|Figure 1 - Sketcher constraint enable / disable with right mouse button while
The example shows how the right mouse button toggles the enable / disable (exclusion) of the "H",
For Figure 2 this horizontal constraint was disabled so the sketched line
can be close to but not constrained as horizontal.
Another trick is to lock a sketcher constraint. This is also done with the right mouse button while
simultaneously holding the shift button (shift + right mouse button). Simply start sketching, then when
the desired sketcher constraint is highlighted red press the shift & right mouse button. The example
in Figure 2 shows how the right mouse button locks and unlocks the perpendicular constraint.
|Figure 2 - Sketcher constraint locking toggle with the Shift + Right Mouse
A circle around the constraint indicates it is locked. The circles go away when the
sketching sequence is complete. Try it to see how it works.
Sketcher dimension locking is similar. Once a sketch is started, a dimension can be locked so that moving
other entities in the sketch doesn't change the locked dimension. In the example shown in Figure 3, the
end of the line segment is moved with the mouse.
|Figure 3 - Moving a vertex without locked dimensions.
Notice which 2 dimensions change as the end of the line segment is moved.
Lock a dimension by selecting the dimension, then using the right mouse button menu, choose "Toggle Lock"
as shown in Figure 4. A locked dimension is indicated by the "L" shown in front of the dimension.
|Figure 4 - Locking sketcher dimensions using the right mouse button menu.
Locking a dimension in sketcher does not effect its ability to be modified either in or out of Sketcher. It
simply keeps it from changing when the sketch is moved by the mouse on the screen.
Using the example of Figure 3 with the angle dimension locked, notice the difference in action caused by
moving the same vertex. Compare Figures 3 & 5. As more dims are locked, sketchers
movement becomes more restricted. Try it. The best way to learn it is to use it.
|Figure 5 - Moving a vertex with a locked dimension.
Compare this with Figure 3. The locked dim makes sketcher find something else to vary as the vertex
As with everything in Pro/E there are bugs with this functionality. For instance if you are trying to lock
a Tangency constraint with an arc, in some cases the arc turns into a conic! And visa versa. So, if it
doesn't work right off, try again. The problem may not be you. Oh well, I guess we take the good with
the bad and continue to laugh at the stupidity of PTC's blunders.