Increasing and decreasing OFFSET / WEAR on older CNC FANUC machines with U and W
Increasing and decreasing OFFSET / WEAR on older CNC FANUC machines with U and W
Many older FANUC system CNC machines, such as FANUC 0T, 6T, 10T, 11T, 15T and some models of 18T, do not have the + INPUT or INPUT CALC button for increasing or reducing the same Offset / Wear value as the newer machines.
Users who start learning CNC from newer machines may be surprised to find that the Offset screen of older machines does not have this function, but it does not mean that they cannot increase or decrease the Offset value, but only use a different input method.
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Can older machines increase or decrease OFFSET / WEAR values?
The answer is yes.
FANUC has already designed an incremental input method for modifying Offset / Wear using the letter of the axis instead of pressing + INPUT.
For CNC lathes include
U is used for the X axis.
W Used for Z-axis
When entering a value and pressing INPUT, the entered value will automatically add or subtract the original value.
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Principles of U and W
On a CNC lathe.
X and Z are Absolute position references.
U and W are incremental transition phase references.
The same principle was used to correct the Offset / Wear value of older FANUC machines.
Therefore, the user does not need to calculate a completely new value. Just specify the desired value to increase or decrease. The system automatically adjusts the original data.
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Example of increasing the X-axis value
Suppose Offset was originally
X = -18.500
Need another 0.020.
Let enter
U0.020
INPUT
Results
X = -18.480
The system will add + 0.020 to the original value.
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Example of X-axis devaluation
Suppose
X = -18.500
Want to reduce another 0.020
Enter
U-0.020
INPUT
Results
X = -18.520
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Example of increasing the Z-axis value
Suppose
Z = 1.300
Want to add
W0.050
INPUT
Results
Z = 1.350
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Z-axis reduction example
Suppose
Z = 1.300
Want to reduce
W-0.030
INPUT
Results
Z = 1.270
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Always have to choose Offset right first.
Before entering U or W, make sure the Offset Number you want to correct must be selected.
If the wrong Offset is selected, the Offset value of the other tool will be corrected immediately. This can result in an error of task size when the tool is called next.
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Note:
Entering a U or W value is an incremental correction of the current value.
Sample
U0.020
Doesn't mean
> Set Offset to 0.020
But means
> Add another 0.020 from the original value.
Likewise.
W-0.030
I mean,
> reduce the current value by 0.030.
Not a new setting to -0.030.
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What's the difference between newer machines?
Many newer FANUC machines have + INPUT, INPUT + or INPUT CALC buttons.
The user simply enters a number and presses it. The system will automatically increase or decrease the original value without typing U or W.
Although the methods of use are different, the basic principle is that increasing or decreasing from the original Offset, only the newer machines are more convenient.
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Summary
Fixing OFFSET / WEAR values on older CNC FANUC machines relies on increased input with U for X and W axes for Z axes instead of using the + INPUT button found on newer machines. Understanding this principle allows operators to adjust job size compensation accurately, quickly, and minimize faults from every new value calculation. It is also an important basis for those who have to work on older CNC FANUC machines that are still in use in many factories to date.


























































































