Chapter 5: Convention Practice in Orthographic Writing

A commonly accepted practice in orthographic projection that modifies strict rules for improved clarity and efficiency.

A type of convention practice where the side view's position is adjusted to save space and improve clarity.

A convention practice that simplifies a side view by removing features hidden from the chosen viewing direction.

This convention practice clarifies dimensioning by showing only the necessary portion of the object.

A convention practice where half the object is shown in a side view for clarity.

This convention practice allows for a view showing only a small, detailed section of an object for increased clarity.

A convention practice that simplifies a drawing by aligning multiple views along a common line.

This convention practice enlarges a specific part of a drawing for detailed representation.

A continuous thin line enclosing a selected portion of a drawing, signifying an enlarged view.

The line indicating the intersection of two surfaces that are modified by fillets or rounds.

A line representing the edge of a surface, visible in the top view of an object.

A line that represents the intersection of two surfaces, especially when fillets or rounds have been applied.

Smooth, rounded transitions between surfaces, used to eliminate sharp corners.

A conventional technique used to accurately represent an object's shape and details.

A visual representation of an object's shape and details, created by projecting lines from the object onto a plane.

When drawing symmetrical features, the convention is to show them in true size and distance from the symmetry axis on adjacent views. This ensures accuracy and clarity.

A line drawn in the middle of a symmetrical object, representing its line of symmetry. This line helps to create a mirror image and is often used in half views.

This symbol indicates a symmetrical feature is represented only by half of it. It's a thin line, often 4H, placed next to the line of symmetry in a half view.

When creating a half view, you can extend the view a bit beyond the line of symmetry without needing a symmetry symbol. It's a more practical representation than using a symbol.

The process of using numbers, symbols, and notes to specify a part's details, such as sizes, locations, materials, and manufacturing processes.

A system where dimensions are expressed using units like millimeters and centimeters.

Lines that extend from a feature to indicate the point where a dimension is being measured.

Lines that show the direction and length of a dimension, with arrows at the ends.

Lines that connect a note to a specific feature, providing additional details about that feature.

Numbers placed on dimension lines to indicate the size or length of a feature.

A dimensioning convention where the dimension figures are placed outside the extension lines, usually when there is not enough space inside.

The practice of maintaining a distance between dimension lines and view lines to ensure clarity and readability.

Dimensions that define the size of features in a drawing, such as width, depth, and thickness.

Dimensions that indicate the position of features in a drawing, such as the location of holes or the angle of a surface.

A curved line used to represent the shape of an arc or a circular feature.

A short line with an arrowhead at one end, used to connect a dimension value to the feature being measured.

A note that provides specific instructions or details related to the dimensions or features of a component.

A graphic symbol used to indicate that a feature is symmetrical, often used in conjunction with a center line or half view.

Dimensioning is the process of adding size and location information to a drawing, enabling the object to be manufactured accurately.

The JIS and ISO standards use millimeters (mm) for length dimensions, and degrees (°) for angular dimensions, with minutes and seconds used when necessary.

Aligned method: Dimensions are placed so they can be read from the bottom and right side of the drawing. Unidirectional method: All dimensions are placed so they can be read from the bottom of the drawing.

Local notes are brief explanatory notes placed near the relevant feature on the drawing. They should be placed outside the view and always read horizontally.

Ensure dimensional figures are clear and readable by avoiding crowding or overlapping. Align dimensions properly and use a consistent style for clarity.

Dimensioning helps to ensure that the object is manufactured according to the intended design. It provides clear and concise instructions for the manufacturing process.

Convention practices are commonly accepted techniques used to simplify and clarify drawings, modifying the strict rules of orthographic projection.

Symmetrical features are often represented by half views, showing only half of the object along the line of symmetry. A symmetry symbol (a thin line) may be used to indicate this.

The curve constructed from two or more arcs, requiring the dimensions of radii and center's location.

A cylinder's size is determined by its diameter and length. Its location is specified by its centerlines, primarily shown in the circular view.

The diameter of a cylinder is shown in a longitudinal view, and is marked with the symbol '' before the figure.

Holes are dimensioned by their diameter and depth, with location determined by centerlines in the circular view.

For small holes, use a leader line and note to indicate the diameter and depth in the circular view.

Large holes are dimensioned using extension lines, diametral dimension lines, and leader lines with notes.

A chamfer is indicated by a leader line and note specifying its linear distance and angle. A 45° chamfer can be marked with a 'CS' symbol.

Avoid crossing dimension lines with extension or leader lines. Keep extension lines from the nearest points. Internal features' extension lines can cross visible lines without gaps. Don't use object, center, or dimension lines as extensions. Avoid dimensioning hidden lines.