Dimensions lines, along with the arrow heads at their ends, show the direction and extent of a dimension. The dimensions value is placed inside a break in the dimension line or above it, or parallel to it.
Never use these as dimension lines:
- A center line
- An extension line
- A phantom line
- A line that is part of the outline of the object or any extension of it
Do not use dimension lines as extension lines.
Dimensions should be aligned and grouped for a uniform appearance.
Leave space between the dimension line and the outline of the object. This should be about 10 mm on the print, or about three text heights. Leave about 6 mm or 2 letter heights between dimensions.
Stagger dimensions for easier reading:
The dimension line of an angle is an arc with its center at the apex of the angle.
Avoid crossing dimension lines. If crossing is unavoidable, do not break the lines.
