170 Section 2 Drafting Techniques and Skills
Bisect an
Angle
CAD
Using a Compass
(Manual Procedure)
1. Angle BAC is given and is to be bisected,
Figure 6-12A.
2. Strike Arc D at any convenient radius,
Figure 6-12B.
3. Strike arcs with equal radii. The radii
should be slightly greater than one-half
the distance from Point B to Point C. The
intersection of these two arcs is Point E,
Figure 6-12C.
4. Draw Line AE. This line bisects Angle
BAC, Figure 6-12D.
Using the Mid Between Points
Object Snap (CAD Procedure)
1. Angle BAC is given and is to be bisected.
Refer to Figure 6-12A.
2. A bisector can be drawn by using the
Mid Between Points object snap. Enter
the
Line
command and pick Point A
as the fi rst point. Then, select the Mid
Between Points object snap. Select Point B
and then Point C when prompted for the
midpoint. This step specifies the second fi
point of the line and draws a bisector.
Figure 6-12. Using a compass to bisect an angle.
A
B
C
A B C D
A
D
B
C
A
D
E
r
r
B
C
A
E
Bisector
of BAC
B
C
Transfer an
Angle
CAD
Using a Compass
(Manual Procedure)
1. Angle BAC is given and is to be trans-
ferred to a new position at Line A′B′ A A ,
Figure 6-13A.
2. Strike Arcs D and D′ at any convenient
radius with the center points at Point A
and Point A′ A A , Figure 6-13B. (Note that
Arcs D and D′ are the same radius.)
3. Adjust the compass to draw an arc
between Points E and F. Strike an arc of
the same radius with Point E′ as the center
point, Figure 6-13C. The point where this
arc intersects the previous arc is Point F′ .
4. Draw Line A′C′ A A through Point F′. Angle ′
BAC has been transferred to Angle B′ A ′ ′C′. A A
Using the Rotate Command
(CAD Procedure)
The following procedure uses the
Copy
option of the
Rotate
command to make a
copy of an existing angle and rotate it to a
desired orientation. The
Reference
option is
used to set the orientation of the angle in
relation to an existing line on the drawing.
The
Align
command can also be used for
this construction, but the
Rotate
command