ALPHABET OF LINES SKETCHING 101 ALPHABET OF LINES

ALPHABET OF LINES SKETCHING 101

ALPHABET OF LINES

VISABLE (OBJECT) LINES § THICK, SOLID LINES § SHOWS THE OUTLINE OF THE OBJECT VISIBLE TO THE EYE

HIDDEN (INVISIBLE) LINES § SHORT, EVENLY SPACED DASHES § REPRESENT SURFACES THAT ARE NOT DIRECTLY VISIBLE TO THE EYE. § ALWAYS STARTS WITH A DASH IN CONTACT WITH A LINE AT ITS START EXCEPT WHEN THE DASH WOULD FORM A CONTINUATION OF A SOLID LINE.

CENTER LINES § ALTERNATING SHORT AND LONG LINES, LINES ARE THIN AND DARK § A LINE THROUGH THE CENTER OF AN OBJECT – ESPECIALLY ONE FOLLOWING AN AXIS OF SYMMETRY (CIRCLE, HOLE, ARC OR CYLINDER)

DIMENSION AND EXTENSION LINES § DIMENSION LINES – SHORT SOLID LINES WITH ARROW HEADS AT EACH END, § BROKEN IN THE MIDDLE TO SHOW DIMENSION OR VALUE § SHOWS THE DISTANCE BETWEEN 2 POINTS § EXTENSIONS LINES – SHORT SOLID LINES USED TO SHOW THE LIMITS OF DIMENSIONS. § PLACED INSIDE OR OUTSIDE THE OUTLINE OF AN OBJECT § THEY EXTEND FROM AN OUTLINE OR SURFACE, BUT DO NOT TOUCH IT.

CUTTING PLANE LINES § A THICK DASHED LINE FOLLOWED BY TWO SHORTER DASHES § TERMINATES WITH A SHORT 90 DEGREE ARROWHEADS § SHOWS WERE A PART IS MENTALLY CUT IN HALF TO BETTER SEE THE INTERIOR DETAIL

SECTION LINES (CROSSHATCH) § THIN EVENLY SPACED LINES, USUALLY DRAWN AT A 45 DEGREE ANGLE. § INDICATES THE MATERIAL THAT HAS BEEN CUT THROUGH IN A SECTIONAL VIEW § USUALLY INDICATED WITH A LETTER TO IDENTIFY THE CUT SURFACE.

BREAK LINES § CAN BE LONG OR SHORT § USED TO INDICATE THE PART IS BROKEN OUT TO CLEARLY SHOW A PART UNDERNEATH § ALSO USED TO REDUCE SIZE OF A DRAWING OF A LONG PART W/ UNIFORM CROSS SECTION § SHORT BREAKS INDICATED BY THICK SOLID HAND DRAWN LINES § LONG BREAKS INDICATED BY THIN SOLID RULED LINES BY FREEHAND ZIGZAGS § BREAKS ON SHAFTS, RODS, TUBES, AND PIPES ARE CURVED

PHANTOM LINES § THIN LINES § INDICATE ALTERNATE POSITIONS OF PARTS OF THE OBJECT § SHOWS REPEATED DETAILS OR LOCATIONS OF ABSENT PARTS § ONE LONG AND TWO EVENLY SPACED SHORT DASHES (LONG DASH ON EACH END)