Instructions

I have highlighted in red bold face the main words we’ll be working with when using a
Sherline machine, and, although many of these words we will not directly use, I wanted you
to be aware of the codes used in industry. A CNC program “word” is defined as an
acceptable letter followed by a real value.
Table 1 —Words acceptable to the EMC interpreter
D
F
G
H
I
J
K
L
Tool radius compensation number
Feedrate
General function (see below)
Tool length offset
X-axis offset for arcs
X offset in G87 canned cycle
Y-axis offset for arcs and Y offset in
G87 canned cycle
Z-axis offset for arcs and Z offset in
G87 canned cycle
Number of repetitions in canned
cycles and key used with G10
M
N
O
P
Q
R
S
T
X
Y
Z
Miscellaneous function (see below)
Line Number
Subprograms
Dwell time with G4 and canned
cycles, key used with G10
Feed increment in G83 canned cycle
Arc Radius, canned cycle plane
Spindle speed
Tool selection
X-axis of machine
Y-axis of machine
Z-axis of machine
Miscellaneous words
M words are used to control many of the I/O functions of a machine. M words can start
the spindle and turn on mist or flood coolant. M words also signal the end of a program
or a stop within a program.
Table 2—M Word List
M0 program stop
M1 optional program stop
M2 program end
M3 turn spindle clockwise
M4 turn spindle counterclockwise
M5 stop spindle turning
M6 tool change
M7 mist coolant on
M8 flood coolant on
M9 mist and flood coolant off
M26 enable automatic b-axis clamping
M27 disable automatic b-axis clamping
M30 program end, pallet shuttle, and reset
M48 enable speed and feed overrides
M49 disable speed and feed overrides
M60 pallet shuttle and program stop
Preparatory Words
Some g words alter the state of the machine so that it changes from cutting straight lines
to cutting arcs. Other g words cause the interpretation of numbers as millimeters rather
than inches. While still others set or remove tool length or diameter offsets. Most of the g
words tend to be related to motion or sets of motions. Table 3 lists the currently available
g words.
79