Sectional Views
centerline
A __________ may be used to represent a cutting-plane line in the sectioned view.
hidden lines
Do not draw __________ ___________ on sectional views unless they are directly needed for clearly describing the shape
spokes; gear teeth
Do not draw section lines on ______ and _________ ________ when a cutting plane passes through them
lengthwise; across
Do not draw section lines on shafts, bolts, and pins, etc. when the cutting plane passes through them ____________; they should be when parts are cut _________ the axis.
section lining
If a cutting plane passes through ribs or webs parallel to the flat side, __________ __________ is NOT drawn for the part.
exaggerated; note
If an incline in a drawing is too subtle in true project, the incline is often _________ and the true incline indicated in a _________.
rotated; completely
Some features on symmetrical pieces should be _________ to show true shape; only the parts that extend __________ around the vertical axis are drawn with section lining.
hatch
The _____ command is used to create section lining.
direction; behind
The arrows on cutting plane lines show the _____________ of the sectional view; the view will always be placed ___________ the arrowheads.
"S" breaks
The conventional breaks for cylindrical bars and tubing are known as _____.
general; any
Thin, evenly-thick and evently-spaced lines are used as a ___________ hatch for __________ material.
different angles
When a sectional view contains more than one assemble piece in section, the section lines must be drawn at _____________ _____________ for each piece.
rotate; directly
When drawing a section or elevation of parts with holes arranged in a circle, _______ two holes until two of them line __________ on the cutting plane.
vertical section
full section taken from an object's front view
profile section
full section taken from an object's profile view
broken-out section
only section where hidden lines are acceptable; shows an object as it were look if a portion were partly cut away by cutting plane and then the rest broken off to reveal cut surface inside; bounded by short break line drawn freehand (.7mm)
DIMSTYLE
opens manager to modify number of decimal places in a dimension
cutting plane
path of imaginary "knife" that cuts through an object
alternate section lining
pattern made by leaving out every other section line; can be used to show rib or another flat part when part otherwise would not be shown clearly
intersection
point where two parts join; approximated sections usually drawn (true projection time-consuming to draw)
full section
shows an object as if it were cut completely from one end of the object to the other
half section
shows an object as if one-quarter were cut away; two cutting planes for right angles to each other; useful when drawing a symmetrical object (according to book; not of much use according to Mr. Irby)
associative hatch
updates the hatch as the hatched object changes
pick points; select objects
In AutoCAD, use the ______ _________ (which allows you to pick a point anywhere within each area to be hatched) and ________ ________ (which allows you to pick an object to be hatched) buttons to specify the area to be hatched.
all
In a sectional view, you should normally include ___________ lines that would be visible on or beyond the plane of the section.
0; 45
The default angle in AutoCAD is ______ and it produces lines slanted __________ degrees.
3DCLIP
activates front and back clipping planes to use on a 3D model to display a full section ONLY; for others, create a 2D isometric w/section in 3D
section lining
also called crosshatching; marks cut surface with thin, dark lines (.35mm); generally 1/8" apart; can be drawn at any angle not parallel or perpendicular to the drawing and to any object lines (usually 30, 60, or 45)
revolved section
also called rotated section; used when part is long and thin and when its shape in cross section is the same throughout; cutting plane is passed through an object, and cut surface is then rotated 90 deg
offset section
section by which the cutting plane is stepped through a number of features that would otherwise not be seen in true projection
auxiliary section
section that results from a cutting plane passing through an object at an angle
sectional view
shows an object as if part of it were cut away to expose its insides
aligned section
shows holes on an object that are arranged in a circle with their true distance from the center by rotating them until two lie squarely on the cutting plane
outline sectioning
shows section lines only along the borders of a part
cutting plane line
shows where the cutting plane passes through the object; represents the edge view of the cutting plane; second-thickest line on page after border (approx. .9mm)
thin section
solid material is shown instead of section lines for parts such as gaskets
ANSI31
standard material symbol in CAD (also cast iron)
conventional breaks and symbols
used to show that a uniform part of a very long object has been cut out of drawing
removed section
when a sectional view is taken from its normal place on the view and moved to somewhere else on drawing sheet; makes drawing easier to understand when positioned in normal place on view (cannot be rotated); identified with bold letters; can be revolved section or show additional detail visible beyond cutting plane; can be drawn at different scale than rest of drawing (if scale is then indicated)
