Home in place (no switch) and machine cordinate offset.

Hi
Working on a knee mill conversion from UCCNC to LinuxCNC. The knee is the Z axis. When I home, the knee is all the way down at a visual mark and the machine coordinate is set to 14.00. I’m trying to get the same thing to happen with Linuxcnc but can’t seem to make it happen. These are the settings I’m using:


MIN_LIMIT = 0.00
MAX_LIMIT = 14.00
HOME = 14.00
HOME_OFFSET = 14.00
HOME_SEARCH_VEL = 0
HOME_LATCH_VEL = -0
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = 0

I have tried a lot of combinations of home and home offset. Swapping 0 and 14. -14 etc etc and no matter what the Z machine coordinate is always 0.00 when I click the home button.

Any advice?
Thanks.
Derek

 

Derek240 wrote:

Hi
Working on a knee mill conversion from UCCNC to LinuxCNC. The knee is the Z axis. When I home, the knee is all the way down at a visual mark and the machine coordinate is set to 14.00. I’m trying to get the same thing to happen with Linuxcnc but can’t seem to make it happen. These are the settings I’m using:


MIN_LIMIT = 0.00
MAX_LIMIT = 14.00
HOME = 14.00
HOME_OFFSET = 14.00
HOME_SEARCH_VEL = 0
HOME_LATCH_VEL = -0
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = 0

I have tried a lot of combinations of home and home offset. Swapping 0 and 14. -14 etc etc and no matter what the Z machine coordinate is always 0.00 when I click the home button.

Any advice?
Thanks.
Derek

Are you saying that the you don't get any movement ?

if so:-
HOME_SEARCH_VEL = 0 this has to be a value
HOME_LATCH_VEL = -0 this has to be a value the -ve sign means it reverses

Hi Clive

No it's a home in place setup with no switches or movement.

Hi Andy

I'm pretty sure that is what I'm doing now and yes it has the correct envelope but the machine coordinate with the knee down is 0.00 and I need it to be 14.00. I have a lot of code already with G53 G00 Z14.0 in it and I'd rather not have to edit all of it.

Hi Andy

I'm thinking you are correct about the offset not working with immediate homing. No matter what combo I tried I could not get the machine coordinate to be anything other than 0.00.

If I add a home switch and set the home offset to 14 I wonder if it would set the machine coordinate to 14.00. I don't need a switch but that is a ton easier than fixing a lot of code.

Thanks