Download User Manual V2.5, 2012-01-18

User Manual V2.5, 2012-01-18
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where 5211 is the X axis offset and so on. If you are seeing unexpected positions as the result of a commanded move, as a result
of storing an offset in a previous progam and not clearing them at the end then issue a G92.1 in the MDI window to clear the
stored offsets.
If G92 values exist in the VAR file when EMC2 starts up, the G92 values in the var file will be applied to the values of the current
location of each axis. If this is home position and home position is set as machine zero everything will be correct. Once home
has been established using real machine switches, or by moving each axis to a known home position and issuing an axis home
command, any G92 offsets will be applied. If you have a G92 X1 in effect when you home the X axis the DRO will read X:
1.000 instead of the expected X: 0.000 because the G92 was applied to the machine origin. If you issue a G92.1 and the DRO
now reads all zeros then you had a G92 offset in effect when you last ran EMC.
Unless your intention is to use the same G92 offsets in the next program, the best practice is to issue a G92.1 at the end of any G
Code files where you use G92 offsets.
11.5
Sample Program Using Offsets
This sample engraving project mills a set of four .1 radius circles in roughly a star shape around a center circle. We can setup the
individual circle pattern like this.
G10 L2 P1 X0 Y0 Z0 (ensure that G54 is set to machine zero)
G0 X-0.1 Y0 Z0
G1 F1 Z-0.25
G3 X-0.1 Y0 I0.1 J0
G0 Z0
M2
We can issue a set of commands to create offsets for the four other circles like this.
G10
G10
G10
G10
L2
L2
L2
L2
P2
P3
P4
P5
X0.5 (offsets G55 X value by 0.5 inch)
X-0.5 (offsets G56 X value by -0.5 inch)
Y0.5 (offsets G57 Y value by 0.5 inch)
Y-0.5 (offsets G58 Y value by -0.5 inch)
We put these together in the following program:
(a program for milling five small circles in a diamond shape)
G10
G10
G10
G10
G10
L2
L2
L2
L2
L2
P1
P2
P3
P4
P5
X0 Y0 Z0 (ensure that G54 is machine zero)
X0.5 (offsets G55 X value by 0.5 inch)
X-0.5 (offsets G56 X value by -0.5 inch)
Y0.5 (offsets G57 Y value by 0.5 inch)
Y-0.5 (offsets G58 Y value by -0.5 inch)
G54 G0 X-0.1 Y0 Z0 (center circle)
G1 F1 Z-0.25
G3 X-0.1 Y0 I0.1 J0
G0 Z0
G55 G0 X-0.1 Y0 Z0 (first offset circle)
G1 F1 Z-0.25
G3 X-0.1 Y0 I0.1 J0
G0 Z0
G56 G0 X-0.1 Y0 Z0 (second offset circle)
G1 F1 Z-0.25
G3 X-0.1 Y0 I0.1 J0
G0 Z0
G57 G0 X-0.1 Y0 Z0 (third offset circle)
G1 F1 Z-0.25