Guidelines for Line Types and Thicknesses in Drawings
Only use the types and thicknesses of lines indicated in the accompanying table. When using other types of lines not specified, or used in applications other than those listed in the table, the conventions chosen should be indicated in other international standards and should include a legend or appendix on the drawing concerned. In the following figures, one can see the different types of lines and their applications. The attached table specifies different types, their designations, and applications.
Online Appointment General Applications
Full thick
A1 contours seen
Ridges overlooking A2
Fill out fine (straight or curved)
Lines B1 fictitious views
B2 dimension lines
B3 projection lines
B4 reference lines
B5 rayados
Outlines of sections battered B6
on the drawing surface
B7 short axis
Fill fine show of hands (2)
Fill out fine (straight) with zigzag
Limits C1 views or partial cuts
or interrupted, if these limits
D1 is not broken lines and points
Thick dashed
Fine stroke
E1 hidden contours
Hidden ridges E2
F1 hidden contours
Hidden ridges F2
Thin dash-dotted
G1 axes of revolution
Trace G2 symmetrically
G3 trajectories
Thin dash-dotted, thick at the ends and changes of address
Trace H1 shear plane
Thick dash-dotted
J1 indication of lines or surfaces
specifications that are being
private
Fine lines and double point
Contours of adjacent pieces K1
K2 intermediate and extreme positions
moving parts
K3 centers of gravity lines
K4 initial contours before
formed
K5 parties located in front of a
shear plane
(1) This type of line is used particularly for designs implemented in an automated fashion.
(2) Although there are two options available, simply use a line type in the same drawing. In addition to its line, the lines differ by their width or thickness. In the tracings in pencil, this differentiation is done by varying the pressure of the stylus, or by using pencils of different hardnesses. In the tracings in ink, the line width should be chosen depending on the size or type of drawing, including the following range: 0.18 to 0.25 – 0.35 – 0.5 to 0.7 – 1 – 1.4 to 2 mm. Given the difficulties experienced in certain reproductive procedures, it is not recommended to use line width 0.18. These values of widths, which may seem random, actually respond to the need for expansion and reduction levels, since the relationship between A4 and A3 is approximately 
. Thus, to extend an A4 format with thick lines 0.5 to A3 format, these lines would then be 5 x
= 0.7 mm. The relationship between the widths of the thin and thick lines in the same drawing shall not be less than 2.
Should be kept the same line width for the different views of a piece, drawn with the same scale.
The minimum spacing between parallel lines (including the representation of the scratched) should never be less than twice the width of the thicker line. It is recommended that this space is never less than 0.7 mm.
In the representation of a drawing, it can happen that different types of lines overlap, so the rule has established an order of preference when it comes to representation. That order is as follows:
1. Contours and edges seen.
2. Contours and edges hidden.
3. Traces of cutting planes.
4. Axis of revolution and traces of the plane of symmetry.
5. Lines of centers of gravity.
6. Projection lines contiguous contours or assembled parts together must match, except for black thin sections. A reference line is used to indicate an element (dimension line, object, outline, etc.). The reference lines must end:
1. At one point, if just inside the boundary of the object represented.
2. In an arrow, if you end up in the contour of the object represented.
3. No point and arrow, if just a dimension line.
1. The lines of symmetry axes have to protrude slightly from the contour of the part and also the center of circles, but should not continue from one view to another.
2. In the circles, the axes have been cut, and not cross; if the circles are very small, thin solid lines are drawn.
3. The axis of symmetry may be omitted in rooms whose symmetry is perceived clearly.
4. The axis of symmetry, when averages or fourth hearing, shall at its ends, two small parallel lines.
5. When two dashed lines are parallel and are very close, alternating strokes are drawn.
6. The dashed lines, whether you end up in a continuous line or lines, end up in line.
7. A broken line will not cut when crossed to a continuous line or another stroke.
8. Stroke arches finished in the points of contact.