PRIN. OF DRAFTING AND SHOP DRAWINGS - OD1641 - LESSON 1/TASK 4
LINE CHARACTERISTICS AND
(4) Extension Line.
lines of the outline.
They are started about one-sixteenth of an inch away from
the view outline.
(5) Dimension Line.
Size is indicated on drawings by dimensions.
dimensions are placed in a break in the dimension line. Some dimensions are placed
between arrowhead tipped lines. In either case, the dimension distance is from the
point of one arrowhead to the point of the other arrowhead.
Normally, to keep
dimensions clear, they are placed outside the view; sometimes, out of necessity,
they are placed inside.
(6) Leader Line.
Leaders are used as connectors between names and the proper
lines they represent, to avoid confusion.
The pointing end of the leader is
usually tipped by an arrow. The note or name used with the leader is located in a
clear space that is not covered by the views or dimension lines of the drawing.
(7) Phantom Line. These lines show possible alternate positions of moving parts.
They are composed of alternating one long and two short dashes evenly spaced with a
long dash at each end.