Page 31 - Engineering drawing from first principles using AutoCAD

24 Engineering drawing [rom first principles

Table 1.3 Recommended abbreviations for drawing notes

Term Abbreviation or symbol

Across flats A/F
Assembly ASSY
Centres CRS
Centre line cor Cl
Chamfered CHAM
Cheese head CH HD
Countersunk CSK
Countersunk head CSK HD
Counterbore C'BORE
Cylinder or cylindrical CYl
Diameter (in a note) DIA
Diameter (preceding a dimension) o
Drawing DRG
External EXT
Figure FIG.
Hexagon HEX
Hexagon head HEX HD
Insulated or insulation INSUl
Internal INT
left hand lH
long lG
Material MATl
Maximum MAX
Minimum MIN
Number NO.
Pattern number PATT NO,
Pitch circle diameter PCD
Radius (preceding a dimension, capital letter only) R
Required REQD
Right hand RH
Round head RD HD
Screwed SCR
Sheet SH
Sketch SK
Specification SPEC
Spherical diameter (preceding a dimension) S0
Spherical radius (preceding a dimension (~) SR
Spotface S'FACE
Square (in a note) SQ
Square (preceding a dimension) D or~
Standard STD
Undercut U'CUT
Volume VOL
Weight WT

For convenience on A4 sheet drawings I use a standard arrow 4mm long by 2mm wide
for dimensions and leader lines. If larger arrows are required I use the SCALE feature on
the Modify menu and choose a value between 1 and 2. This not only increases the size of
the arrow but keeps the length and width to the same proportions. Table 1.2 gives a
minimum value of 5mm for drawing numbers on A4 sheets. It is therefore convenient to
keep the same text style, and whenever larger numbers and letters are required simply
use the scale value greater than 1. It is time consuming to keep on changing text styles.