Chapter 5: Convention Practice in Orthographic Writing

A commonly accepted practice in drafting that deviates from strict orthographic projection rules for improved readability and clarity.

A type of convention practice where the side view is positioned next to the top view, particularly when the object's height is small and depth is large. It saves drawing space and enhances clarity.

A side view that omits features that are obscured by other features or would be difficult to see clearly from the chosen viewing direction.

A side view that shows only a portion of the object to highlight specific features or dimensions.

A side view that only shows half of the object, usually done when the object is symmetrical.

A side view that concentrates exclusively on a particular region or detail on the object. It's beneficial for emphasizing small, intricate elements.

A convention practice where the side view is aligned with the front view, especially when the object is complex and requires a clearer representation of its shape.

A convention practice that enlarges a portion of the object for better detailing and clearer representation of intricate features.

A type of view that clarifies object features by rotating them to true size on an adjacent view.

Sometimes, a partial view only needs to show half of the object, making it a half view.

The line of symmetry is used in half views but is not drawn with a continuous line.

Half-views can be created by drawing the views slightly beyond the line of symmetry.

A drawing technique that gives the impression of a hole at the center of the plate.

A drawing technique that gives the impression of holes at unsymmetrical positions.

A drawing technique that creates a representation of an object's ribs.

A drawing technique that combines the representation of an object's ribs and holes.

A drawing technique that creates a representation of an object's ribs, holes, and keyway.

A line that shows the hidden intersection of surfaces in an object where fillets and rounds are present.

When a true projection of an object with fillets and rounds leads to an inaccurate representation, this line is used to show the true intersection of surfaces as if the fillets and rounds were not present.

The dimension figures are placed so that they can be read from the bottom of the drawing.

The dimension figures are placed so that they are readable from the bottom and right side of the drawing.

Dimension lines are used to indicate the size of an object. They are terminated with arrowheads.

A dimension that points to the center of a hole or feature.

A note that clarifies or provides additional information about the drawing.

Common practice for dimensioning holes in drawings where the hole's size is displayed along with the word "drill".

Dimensioning is the process of adding size and location information to a drawing to help manufacture the object.

The unit of measurement for lengths is millimeters without a unit symbol. Angles are measured in degrees with a symbol "o".

Lines connecting a local note to a specific feature on the object.

Numbers that indicate actual size or distance on the dimension lines.

A standardized system of measurement used in technical drawings, typically using millimeters.

A system of measurement used in technical drawings, typically using inches.

The space between dimension lines and the view or other dimension lines, ensuring clarity and readability of the drawing.

Dimensions that define the size of an object, like width, depth, and thickness.

Dimensions that specify the position of features, like the location of a hole or an angle.

A circular dimension line drawn from the center to specify the size of an angle.

The radius of an arc is dimensioned using the letter 'R' followed by the numerical value.

The dimension line for the arc is drawn radially and should have an angle between 30° and 60° to the horizontal.

If an arc's center is outside the drawing sheet or interferes with other views, use a shortened radial dimension line.

To dimension fillets and rounds, use a local note specifying the radius. If all fillets and rounds have the same size, use a note like “All fillets and round are Rxx”.

A curve formed by joining two or more arcs, requiring dimensions for radii and their center locations.

A geometric shape with circular cross-sections, defined by its diameter and length. Location is indicated from its central axis in a circular view.

The diameter of a cylinder is usually indicated in a longitudinal view using the '' symbol.

Holes are characterized by their diameter and depth, with location specified from their centerlines in a circular view.

For small holes, use a leader line and local note to indicate the hole's diameter and depth in the circular view. This clarifies the hole's size and depth.

Larger holes are represented using extension, diametral, or leader lines with dimensions.

A chamfer is a slanted edge created by cutting off a corner, represented by a leader line and a note indicating its angle and length.

Extension, leader, and dimension lines should be drawn carefully to ensure clarity and readability in a drawing.