Scales used in drafting include the mechanical engineer's scale, the civil engineer's scale, the architect's scale, and the metric scale.
Types of Scales in Engineering Drawing:
- Plain scale.
- Diagonal scale.
- Vernier scale.
- Comparative scale.
- Scale off chords.
Scale - In drafting, architecture and engineering the term scale has two meanings. A scale is a dimension that represents the structure shown in a plan. A scale is also a ruler used in drawing and measuring architectural and engineering plans. Architectural scales units are based on foot/inch dimensions.
Referred to as 1:10, 1:20, 1:30,1:40, 1:50 or 1:60 scale. Typically in civil engineering applications, 1:10 (1″=10′) is used exclusively for detail drawings. 1:20 and 1:40 scales are used for working plans. 1:60 is normally used only to show large areas of a project.
The scales are classified into four categories:
Plain Scale. Diagonal Scale. Vernier Scale. Scale of chords.
Plain scales, 2. Diagonal scales, 3. Vernier scales, 4. Comparative scales and 5.
Scale allows us to understand the relationship between a representation - a drawing or model - and reality. Being able to draw accurately to scale, and to shift fluidly between scales, is one of the most important aspects of architectural drawing and spatial design.
Scales are generally expressed as ratios and the most common scales used in furniture drawing are 1:1, 1:2, 1:5, and 1:10 for reducing and possibly 2:1 for enlarging.
A 1/4" scale means that each 1/4" (inch) on the plan counts for 1' (feet) of actual physical length. To scale a blueprint in imperial units to actual feet. multiply the measurement on the drawing (in inches decimal equivalent) with the denominator.
Definition: Scaled Drawing. A drawing that shows a real object with accurate sizes reduced or enlarged by a certain amount (called the scale).
Architect scales, such as 1/4˝ = 1´-0˝ (1/48 size) or 1/8˝ = 1´-0˝ (1/96 size), are used for structures and buildings. They are used to measure interior and exterior dimensions such as rooms, walls, doors, windows, and fire protection system details. Other scale tools include flat scales and rolling scales.
There are six dissimilar plain scales in metric which are ideal for engineers, Architects and Surveyors. By applying diagonal scale, it becomes simpler to calculate three dimensions like metres, decimetres and centimetres, units , tens and hundreds; yards, feet and inches etc.
There are 3 types of scale: 1) Visual Scale- it refers not to the actual dimensiond of things but rather to how small or large something appears to be in relation to its normal size. 2)Hierarchical Scale- refers to the deliberate use of relative size in a work of art, in order to communicate differences in importance.
A scale drawing of a building (or bridge) has the same shape as the real building (or bridge) that it represents but a different size. Builders use scaled drawings to make buildings and bridges. A ratio is used in scale drawings of maps and buildings.
Site plans are often drawn at 1/200th (1 to 200) or even 1/500th (1 to 500) of actual size. A scale of 1 to 100 is indicated on a drawing using the code 1:100.
The civil engineer's scale divides 1 inch into equal decimal units of 10, 20, 30, 40, 50, 60 and 80. Plans drawn in 10 scale may show scales such as 1 inch = 10 feet, 1 inch = 100 feet. The 20 scale is used for scales such as 1 inch = 2 feet, 1 inch = 20 feet and 1 inch = 200 feet.
You can see there are four different types of measurement scales (nominal, ordinal, interval and ratio). Each of the four scales, respectively, typically provides more information about the variables being measured than those preceding it.
Nominal, ordinal, interval, and ratio data
Going from lowest to highest, the 4 levels of measurement are cumulative. This means that they each take on the properties of lower levels and add new properties.
For residential structures, the 1/4-inch scale is usually used, roughly equivalent to 1:50 in metric scale (Figure 4.5). For large commercial buildings, smaller scales may be used. Exterior elevations are often drawn to 1/4-inch scale.
Definition: Scaling technique is a method of placing respondents in continuation of gradual change in the pre-assigned values, symbols or numbers based on the features of a particular object as per the defined rules. All the scaling techniques are based on four pillars, i.e., order, description, distance and origin.