HOW TO SKETCH LIKE AN ENGINEER Line Conventions
What are line conventions? Line conventions convey information about the shape and size of an object Line conventions enables builders to recreate objects based on a drawing In other words, line conventions are used to make blueprints.
Construction Lines Construction lines are your basic outline of your drawing Drawn as lightly sketched lines Help you to layout your idea on paper and add non-linear figures
These lines will layout your final drawing Object lines are drawn as solid, thick lines. Not drawn free hand, done using a ruler, compass, etc. Object Lines
Lines not readily apparent in a view of an object are hidden lines. Hidden lines are evenly- spaced, short dashes that begin and end as a dash in contact with the line from which it starts and stops. Used to show details that can’t be seen from all views Hidden Lines
Center lines are used to indicate the center of a circle, arc, or any symmetrical object. Center lines are composed of long and short dashes, alternately and evenly spaced, with a long dash at each end. Center lines
Dimension lines are made up of a straight line with an outward facing arrow on each end. They show the distance between two points on an object Dimension figures for parallel dimension lines are staggered. Dimension lines
Extension lines are thin lines that extend from the object outline or point on the object to a place outside the image area. Extension lines are always used with dimension lines Extension lines do not touch the object lines (leave 1/16”) Extension lines project 1/8" beyond the outermost dimension line. Extension and dimension lines are drawn at right angles to each other. Extension lines
Notes or dimensions that pertain to surfaces or parts use leader lines. Leader lines are thin, solid lines that terminate in an arrowhead or dot. Use arrowheads when leader lines terminate at the outline of an object. Use dots when leader lines terminate within the outline of the object or on the surface of the object Leader lines