Graphic Design & Printing TechnologyA drafting machine is a device which is mounted to the drawing board. It has
rulers whose angles can be precisely adjusted with a controlling mechanism.
There are two main types of apparatus: an arm-type parallelogram apparatus
based on a hinged arm; and a track-type apparatus which moves on a rail
mounted to the top of the drawing board. Small drafting machines (mini drafters)
are commonly used.
Rulers
Rulers also called Architect’s scale used in technical
drawing are usually made of polystyrene. It is available
in two types according to the design of their edge as
(1) Straight edge and grooved edge.
LETTERING AND DIMENSIONING
Writing of titles, dimensions, notes and other
important particulars on a drawing is called lettering.
Lettering can be done in different ways such as hand
lettering, mechanical lettering etc. Mechanical lettering can be done using
typewriter or computer.
Dimensionis a numerical value expressed in appropriate units of measurement
and marked on a drawing with lines, symbols and notes. The dimension without
any unit is considered in ‘mm’. The elements of dimensioning are projection
line or extension line, dimension line, leader line and arrowheads. Projection
line is a thin, dark, solid line that extends from a point on the drawing to which
a dimension refers. A dimension line is a thin line that shows where a
measurement begins and where it ends. The dimension line should have a
break in it for the dimension numbers. Dimension line should be at least 10mm
from the lines of the drawing. Leader lines are thin lines drawn from a note or
a dimension to the place where it applies. Arrowheads are used at the ends of
An architect’s scale
(Rulers)