Chapter 7 Computer-Aided Drafting and Design 169
fillet fi is an arc representing an inside rounded t
corner. A chamfer is an angled line drawn r
where two straight lines would normally
meet at a corner. Rounds, fi llets, and cham-
fers are used to smoothen sharp edges. See
Figure 7-18. Rounds and fi llets can be drawn
with the Fillet command. After entering the
command, the fi llet radius is set. Then, the
two lines, circles, or arcs forming the intersec-
tion are selected. The original objects are then
trimmed and the arc is automatically drawn.
A chamfer can be drawn with the Chamfer
command. After entering the command,
the chamfer distances from the two lines to
the corner are set. A 45° chamfer is created
with equal distances. Next, the two lines are
selected. As with the Fillet command, the
lines are trimmed automatically when the
chamfer is drawn.
Trimming and Extending Lines
Many objects in a CAD drawing are made
up of lines. During the drawing process, it is
sometimes necessary to “clean up” areas of
the drawing where lines must intersect accu-
rately. Trimming is useful when two lines
overrun past a corner. Extending is useful
when a line must be lengthened to meet an
edge or other entity.
The Trim command is used to trim lines,
arcs, and circles. After entering the command,
a cutting edge must be specified. This repre-
sents the point to where the object is trimmed.
Next, the object to be trimmed is selected.
The portion of the object exten ding past the
cutting edge is automatically removed. When
using the Trim command, you can select as
many cutting edges and objects as needed to
complete the trim operation.
A
B
1
_
2
2
1
_
2
2
3 _
16
R
_
2
∅1
_
8
∅7
_
2
1 _
2
3
_
8
5
_
8
∅1
2
9
–16NC–2
3
_
32
× 45°
Fillets
6
Chamfered
edges
Figure 7-18 Creating rounded and angled features. A—Fillets are created by specifying a fi llet radius and
selecting the two objects forming the intersection. B—Chamfers are created by selecting two lines and entering
the chamfer distances.