Specifications

Southwestern Industries, Inc.
ProtoTRAK SMX K2, K3, K4 & Retrofit Safety, Installation, Maintenance, Service & Parts List Manual
112
5.2.2.2 Backlash Compensation
Code 11: Set X or Y backlash constant
Note: this procedure is on systems with TRAK Sensors or Glass Scales only.
Go to setup mode, go to section “B” and press CODE 11. Refer to service code section for
further explanation.
Code 127: Set X or Y Backlash Constant
Note: this procedure is only for systems without TRAK Sensors or Glass Scales.
Every mechanical system has at least a little backlash or lost motion. It is produced by the
small amount of play between the gibs and ways, and mostly by the accumulative bending
or elasticity of all the parts of the drive train under load. The backlash constant is factory
set, but may need to be adjusted periodically.
1. Set a .0001-inch dial indicator in the spindle, and touch off on a block or the vise along
the direction (X or Y) you wish to check, or set the backlash constant.
2. Turn on the ProtoTRAK and at the Main Menu, follow the procedure below precisely:
Conversation Says You Do
a. ---
a. Press MODE
b. Select Mode b. Press SET UP
c. Select c. Press SERV CODES
d. Select d. Press “B”
e. Select Code 127
e. Press X or Y
f. Backlash Value = _ _ _ _
f. What is shown is the current value.
Follow the instruction on the screen
and press the appropriate soft keys.
Wait a few seconds between each
INCR VALUE or DECR VALUE
press.
g. The following is an example of what you
might see when running this code.
For example, if the up and down "Oscillation
Value" shown in the conversation line is .00278
inch, and the dial indicator is moving back and
forth .0012, then the true backlash value is
.00278 -.0012 = .00158 inch. Input this by
pressing MODE, SET UP, SERV CODE, 128, SET
and then .00158, SET, RETURN.
3. The X backlash identified and stored in Step 2 should be less than 0.003” on a new
machine. If it is appreciably larger, inspect the drive train for loose bolts, brackets,
bearings, etc.
The backlash can also be found manually with a 0.0001” indicator with the following
method.
• Load the indicator to zero from one direction and zero out the DRO.
• Move the indicator to 0.002” and then back to zero. Do not over shoot 0,
otherwise start over.