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AutoCAD and Its Applications—Basics
Reference Option
The
Reference
option is an alternative to entering a rotation angle and allows you
to specify a new angle in relation to an existing angle. For example, use the
Reference
option to rotate a gear from 150° to 0°. Choose the
Reference
option and specify
the current angle, 150° in the example, at the
Specify the reference angle
current:
prompt. Next, specify the angle at which the objects should be, 0° in the example. See
Figure 12-5A. Use the
Points
function of the
Reference
option to specify the new angle
using two points not associated with the selected base point.
PROFESSIONAL E O O N TIP T T P P R O R O F FE S S I O NA NA AL T TI P
Specify the reference and new angles using specific values; or choose fi
points, often on existing objects, as shown in Figure 12-5B. Picking
points is especially effective when you do not know the exact refer-
ence and new angles.
Figure 12-5.
Using the
Reference
option of the
ROTATE
command to rotate a gear on an assembly
drawing according to the current angle of the objects. A—Entering reference angles.
B—Selecting points on a reference line.
2. Specify the current
rotation angle
1. Select the base
point (center)
Original 150° Rotation Rotated to 0°
A
150°
3. Specify 0° as the
new rotation angle
3. Specify 0° as the
new rotation angle
Unknown
angle
1. Select the base
point (center)
Original Unknown Rotation Rotated to 0°
2. Pick two points
to specify the
rotation angle
B