AutoCAD has had the ability to create solid primitive objects, like cylinders, all the way back to AutoCAD Release 12. However, until AutoCAD 2007, those objects were not easily editable. You practically had to know exactly what you wanted to draw before you started. That might work for creating as-built models but it made conceptual design challenging and time-consuming. Fortunately, AutoCAD 2007 took a huge leap towards true conceptual design. You can easily edit primitive objects using grips or the Properties window. For example, as I create the design for my air hockey paddle, I can experiment with the size and shape of the existing cylinder. Selecting a cylinder displays grips a move grip (square) at the center of its base. Picking that grip makes it easy for me to move the cylinder to another location (just as you would expect from your 2D experience).
Selecting one of the four quadrant grips enables you to edit the radius of the cylinder (again, just like you expect when editing a 2D circle).
Selecting stretch grip at the center of the base enables you to change the height and, at the same time, change the location of the base.
Selecting the grip at the other end of the cylinder enables you to edit the height of the cylinder without changing its base.
Did you notice that I described that grip as being “at the other end” rather than being at the “top”? That’s because the base could just as easily be on top (or on the side or anywhere else). I could, for example, grip edit the “top” of this cylinder, and drag it below the base… now it’s the bottom.
The importance of distinguishing between the base of a solid primitive object and “the other end” will become more apparent in future posts.
Key concept:
- Grip edit to modify the size and shape of a solid cylinder
Subscribe