Specifications
170 
Southwestern Industries, Inc. 
TRAK LPM Programming, Safety, & Operating Manual 
15.6.2   4
TH
 AXIS ON / OFF 
This soft key enables and disables the use of the 4
th
 axis servo, as well as the 
programming options available to the user. When turning on the 4
th
 axis, you will 
need to home the machine again so that the 4
th
 axis gets homed as well. If the 4
th
axis option is turned off, you will get a prompt stating that you will lose your 
current program in memory. 
15.7 PROG I/O 
If opening a program that contains 4
th
 axis specific events, and the 4
th
 axis option 
is not activated on the machine, the system will give an error message. You must 
enable the option under service code 318 (see section 15.0). If the 4
th
 axis option 
is turned off, and a program containing 4
th
 axis events is opened, the system will 
automatically turn it on for you. 
15.7.1 4
th
 Axis G-Code notes 
The ProtoTRAK PMX is capable of running 4
th
 axis G-Code. In addition to all the 
codes found under section 14.11.1, please use the additional notes below when trying 
to define your post processor. 
1.  The 4
th
 axis is defined by A, and is always assumed to be parallel to the X axis. 
2.  Only G00 and G01 commands support movement along the A axis. The format 
will look like the following: 
G00 X1.0 Y2.0 Z3.0 A4.0 
G01 X5.0 Y6.0 Z7.0 A8.0 
3.  The feedrate along A must be defined in inches per minute. Feedrate is calculated 
in relation to the centerline of the part, which our system is always keeping track 
of using service code 506. 
4.  M10 – Turn ON Auto Clamp for 4
th
 axis (default). With the Auto Clamp turned 
ON, the 4
th
 axis will automatically clamp when the A axis is not programmed to 
move. When the A axis needs to position or feed, it will automatically unclamp 
before doing so. 
M11 – Turn OFF Auto Clamp for 4
th
 axis. Turns off the behavior described 
above, and will remain unclamped during RUN mode. 
5.  For best results when running GCD, the Z axis g-code should be output in relation 
to center of part. Use a 0.0 offset for Z in the part/fix management table. 
6.  The angle for A axis can be defined in incremental or absolute values, using G90 / 
G91, can be positive or negative, and can exceed 360. 
7.  G41 and G42 are not supported when feeding along the 4
th
 axis. G40 must be 
used. 










