DesignSpark Mechanical - Basics - 3d. Sketching - Creating symmetrical features Video Lecture | Design Sparks Tutorial: Become Design Master - 3D & Animation

if we add a construction line vertically
between midpoints we can right click and
make it into a mirror line while this
mirror line is active anything we sketch
on one side of the shape will appear
automatically on the other side
now as we modify the sketch the changes
will appear in both sides of the shape
we'll draw a line to alter the bottom
corner of the sketch notice in the
option panel lines can be drawn using
either polar or car Tasya methods simply
select your preferred option before or
during creation of the line
to finish the modification let's trim
away the lines we don't need the trim
lines tool is one of the sketch tools in
the modify section of the sketch toolbar
area notice when in trim mode that
hovering over lines will show them as
segmented highlighting just the part of
the line which will be trimmed in normal
select mode the whole line will
highlight when we hover over it
all the changes have now been applied to
both sides of the sketch if we want to
resume designing without symmetry just
right-click the mirror line and turn it
off any new features now added will
appear only where they are drawn
you