An exploded view is used to show the relationship between parts of a group.
Each of these line types has a specific purpose in a technical drawing.
show only part of the picture. For this
reason, they must be isolated in some
way. 2-D details are often cut off by
a jagged line. 3-D details might be
enclosed within a circle or fade away at
An exploded view is often used to
show how a collection of parts fits
together. This view is normally a 3-D
The type of line used by a drafter
is also subject to rules. Each type is
selected for a specific purpose. The
most common line types are:
• Feature Outlines/Visible: This heavy,
solid line is used to show the feature
outlines of parts that are visible from
the angle shown.
• Hidden: This medium, regularly
dashed line shows the positions of
features that are internal or behind the
features that are visible from the angle
• Center: This light line is broken
into alternating long and short sections.
It is used to show the axes of holes
and shafts, and the centers of circular
• Section: Collections of these light
lines are used to show cut surfaces as
hatched or cross-hatched areas.
• Dimension: Light lines that flag
the points measured by a dimension.
Lightweight arrows are used
perpendicular to the dimension lines to
bracket the numerical dimension.
• Break: May be heavy or light,
depending on the style. These lines
enclose a portion of a drawing that has
been cut away, like a detail view.
As with views, model designers may
take some liberties with the rules on
lines. Usually these departures are
limited to using a fancy line type to
draw attention to a feature.
Wrapping It Up
Reading a blueprint can require
a degree of skill and knowledge.
Fortunately, most model plans are
simple forms of technical drawings.
Even with that noted, everything on
the plans was put there for a reason.
Taking the time to review the plans
until you clearly understand them
before the build starts is the best way
to avoid problems with the build.
The next time we meet, we’ll discuss
workflow planning and how it can keep
our projects running smoothly.
Grumman Goose plans
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