What is a Common-Size Statement?
Although the projected view of the architectural form has clearly expressed the shape of the form and the relationship between the parts, it must also be marked with sufficient dimensions to determine the actual size of the form and the relative positions of the parts. There are two issues to consider when dimensioning the architectural form: which dimensions and dimensions should be labeled on the projection plan and where on the projection plan.
- In addition to drawing the shape of the building and its various parts, the drawings must also be dimensioned accurately, thoroughly and clearly to determine its size as a basis for construction.
- The dimensions on the drawing are composed of extension lines, dimension lines, dimension start and stop symbols, and dimension numbers. size
- 1. The true size of the machine should be based on the size value noted on the drawing, and has nothing to do with the size of the graphic and the accuracy of the drawing
- 1. When marking the diameter, the symbol "" should be added before the dimension number; when marking the radius, the symbol "R" should be added before the dimension number; when marking the diameter or radius of the spherical surface, the symbol "" or " "S" before "R". For screws,
- 1. If the rounded or chamfered dimensions in the drawing are all the same or a certain size is the majority, you can give a general description in the blank space of the drawing, such as "all rounded corners R4", "all chamfered 1.5 × 45 °", "Remaining fillet R4", "Remaining chamfer 1 × 45 °", etc. 2. The general undercut can be marked in the form of "slot width x diameter" or "slot width x slot depth". 3. In the same figure, for a group of elements such as holes and slots of the same size, the size and number can be noted on only one element. 4. When the positioning and distribution of grouped elements are clearly defined in the graph, the angles may not be marked, and the word "evenly distributed" may be omitted. 5. When there are several similar and repeated elements (such as holes) in the same figure, use the method of marking (such as coloring, etc.) or the method of labeling the letters to distinguish. The size and number of holes can be directly marked on the drawing, or can be expressed in the form of a list. 6. For the same discontinuous surface, connect it with thin solid lines and mark the size once. 7. The dimensions starting from the same datum can be marked in the form of coordinates.
- In the projected drawing of the building shape, in order to complete the dimensioning, the size of the combination can be divided into the following three categories according to the method of shape analysis:
- 1.Fixing size
- 1.Size numbers
- Linear dimension numbers should generally be written above the dimension line, but also allowed at the break of the dimension line. The direction of linear size numbers should generally be noted using the first method. The second method is also allowed without causing misunderstanding. However, in one drawing, one method should be used whenever possible. Method 1: Numbers should be avoided as much as possible within the 30 ° range shown. Method 2: For non-horizontal dimensions, the numbers can be written horizontally at the break of the dimension line. The angle numbers are always written in the horizontal direction, and are generally noted at the break of the dimension line. If necessary, it can also be marked in the form of Figure 7. Dimension figures cannot be passed by any figure, otherwise the figure must be broken.
- 2.Dimension line
- Dimensioning
- The dimension line is drawn with a thin solid line, and its terminal can have the following two forms: a. Arrow: The form of the arrow is shown in Figure 9, which is suitable for various types of patterns. b. oblique lines: oblique lines are drawn with thin solid lines, and their directions and drawing methods are shown in Figure 10. When the end of the dimension line is in the form of a diagonal line, the dimension line and the extension line must be perpendicular to each other. When the dimension line and the extension line are perpendicular to each other, only one type of dimension line terminal can be used in the same drawing. When arrows are used, dots or slashes are allowed to replace the arrows if the status is not sufficient. When dimensioning linear dimensions, the dimension line must be parallel to the labeled line segment. Dimension lines cannot be replaced by other graph lines, and generally they should not overlap with other graph lines or be drawn on their extension lines. When dimensioning an angle, the dimension line should be drawn as an arc whose center is the vertex of the angle. When only half or slightly more than half of the figure of the symmetrical machine is drawn, the dimension line should slightly exceed the symmetrical centerline or the boundary line of the break.
- 3.Extension lines
- The extension lines are drawn with thin solid lines and should be drawn from the contour line, axis or symmetrical centerline of the figure. You can also use contour lines, axes, or symmetrical centerlines as extension lines. When representing the coordinates of points on the outline of a curve, the dimension line or its extension can be used as the extension line.
- Dimensioning