G91 erratic behavior

[Ruslan]

I attached program with erratic G91 behavior. After line N7 execution Z coordinate must be Z+15, but in reality it is Z-5. If G91 stay before G1 program execution is normal. The position of G90/G91 must not influence on execution of whole line of G-code.

PROG1.nc

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May be it is not a bug but after machinig my part it will be a great bug.
May be this could be useful https://tsapps.nist.gov/publication/get ... _id=823374

[dezsoe]

G91 works fine, but don't push it into the G1 line. Try the following:

Code: Select all

O0001
N1 G54 G90
N2 G0 Z50
N3 S2000 M3
N4 X0 Y0
N5 Z30
N6 G1 Z20. F1000.
G91
N7 G1 Z-5. F1000
N8 X20 Y40
G91
N9 G0 Z20
M30

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