y axis negative issue

All,

Yesterday I turned on my machine after not working on it for four days and it acts like it lost its mind. I recently got a Probotix comet with a built in tool sensor and as of yesterday it was trying to use the tool sensor location but in the wrong coordinates, I was able to fix this in G59.3 by zeroing it out on center and setting the z limit at the exact switch trip position.

But today when I turn my machine on select home all it completes the the homing process and returns to G28 which shows x= 13.1000 and y=9.5625 approx but when i go to run a program it gives me an error that line 17 exceeds the y axis. Looking at line 17 and the rest of my code I see that I have several lines that show y being negative numbers such as y -7.625 and so forth.

When I move the machine to the end of the work envelope at the y axis it shows as y -3.25 so it can not go to the y-7.625 position. How do I correct the work envelope to show the correct settings?

Hi,

If you have been messing around with co-ordinate systems and got in a mess, the first thing I would do is delete your .var file, to stop the persistence of values in it.

Then startup and home.
Press # and you should see all axes on zero in G53

Press # again to revert to G54

Then move to wherever you touch off at (bottom left top datum of workpiece is traditional) and touch off each axis.

If your limits settings in your ini file are correct, you will be able to move anywhere you like on the workpiece

If not you need to alter them.
www.linuxcnc.org/docs/devel/html/config/...tml#sub:AXIS-section
The figures are in G53 machine units from the home switches and should be just short of the limit switches at both ends

eg. Z limits
MAX_LIMIT = 0.5 # half mm beyond home
MIN_LIMIT = -70 # max plunge of spindle before hitting limit switch

If you home in the centre of the table, X and Y would have equal negative and positive values, otherwise something similar to Z except the large value would probably be positive.

regards

Thanks I will try deleting the . VAR file and restart the system. I looked the my INI file and I see that the min and max limits do not loo like what you say they should look like. I have included all 3 axis portions of the INI file below.

[AXIS_0]
TYPE = LINEAR
HOME = 13.0
MAX_VELOCITY = 5.0
MAX_ACCELERATION = 6
STEPGEN_MAXACCEL = 30
SCALE = 800.0
FERROR = 0.05
MIN_FERROR = 0.01
MIN_LIMIT = -0.1
MAX_LIMIT = 26.25
HOME_OFFSET = -0.2
HOME_SEARCH_VEL = -0.5
HOME_LATCH_VEL = -0.2
HOME_IGNORE_LIMITS = 1
HOME_SEQUENCE = 1
HOME_FINAL_VEL = 3.0

[AXIS_1]
TYPE = LINEAR
HOME = 12.5
MAX_VELOCITY = 5.0
MAX_ACCELERATION = 6
STEPGEN_MAXACCEL = 30
SCALE = 800.0
FERROR = 0.05
MIN_FERROR = 0.01
MIN_LIMIT = -0.1
MAX_LIMIT = 25.1152
HOME_OFFSET = -0.2
HOME_SEARCH_VEL = -0.5
HOME_LATCH_VEL = -0.2
HOME_IGNORE_LIMITS = 1
HOME_SEQUENCE = 1
HOME_FINAL_VEL = 3.0

[AXIS_2]
TYPE = LINEAR
HOME = 0
MAX_VELOCITY = 0.5
MAX_ACCELERATION = 10.0
STEPGEN_MAXACCEL = 31.5
SCALE = 2000
FERROR = 0.05
MIN_FERROR = 0.01
MIN_LIMIT = -5.25
MAX_LIMIT = 0.1
HOME_OFFSET = 0.2
HOME_SEARCH_VEL = 0.5
HOME_LATCH_VEL = 0.2
HOME_IGNORE_LIMITS = 1
HOME_SEQUENCE = 0

Thank you ArcEye. After deleting my VAR file and setting everything back up it appears my machine is working again. The feed rate is slower now but that is ok. I think my z axis was set way to fast for some detail work I was trying to do so this is a good thing.

Again thank your your guidance in helping me fix my issue, I was starting to pull my hair out. LOL