Standard ✔️✔️formal document that institutes a uniform method to perform an action or defines a
criterion for a product. Standards are defined by organizations such as ANSI (American National
Standards Institute) responsible for regulating many engineering standards used in the US.
Convention ✔️✔️methods and criteria used so extensively that they become dominant and generally
accepted and adopted by the public. They are also known as "industry standards"or "de facto
standards". There are no organizations or formal documents that define conventions. These conventions
can differ between industries or even firms within the same industry.
Standards and Conventions FACT ✔️✔️In the United States, the Y series of the ANSI standards
regulate engineering drawings.
Lettering ✔️✔️-The style of engineering lettering we will use in this course is Single Stroke Gothic
Lettering.
-only capital letters on drawings.
-Each letter and numbers should be 1/8"in height.
-Fractions should be twice normal letter height, but each numeral (numerator and denominator) should
be shorter than 1/8"to allow space for the vinculum (horizontal line which separates the numerals).
Lettering Techniques ✔️✔️Hold the pencil between the thumb, forefinger, and second finger without
gripping it too tightly. The most ergonomically efficient position to hold the pencil is at a 60°angle with
the paper.
Engineering Sketching ✔️✔️Engineering sketches are black and white line drawings with notations
expressing design intent.
•They should always be signed and dated to verify ownership.
•First and foremost, sketching is a form of COMMUNICATION.
Artistic Drawings ✔️✔️concerned with colors, forms, compositions, and other elements that affect the
sense of beauty.
, Technical Drawings ✔️✔️COMMUNICATE technical information, capturing details necessary for
production or modification.
Sketching ✔️✔️Medium grade pencils work best for sketching.
Sketching Techniques ✔️✔️+When sketching LINES,
-keep your eye on the endpoint.
-If necessary, break long lines into short segments by marking the midpoint
-Make quick light strokes initially.
-Darken only the lines you want.
+When sketching CIRCLES and ELLIPSES,
-break large arcs/circles into small segments.
-Sketch a light square/rectangle.
-Lightly sketch in diagonals.
-Mark contact points on square/rectangle.
-Rotate the paper for each segment.
Taxonomy of Projections ✔️✔️Orthographic -PARALLEL PROJ
Axonometric-PARALLEL-PICTORIAL SKETCH
Oblique-PARALLEL-PICTORIAL SKETCH
Perspective-PERSPECTIVE PROJ
Orthographic Projection ✔️✔️is the system of drawing views of an object by projecting them
perpendicularly onto projection planes with parallel projectors.
•Orthographic drawings represent three dimensional objects in separate views arranged in a standard
manner.
•They are called working or detailed drawings if they contain sufficient dimensions, notes, and
specifications to enable a product to be manufactured from the drawings.
+Use multiple line types.