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Offline Davek0974

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Soft limits info please...
« on: February 17, 2014, 04:45:10 AM »
Having just got my hand jog wheel working nicely (thanks Hood) I have uncovered an issue that i need help with

The first cycle runs perfectly - jog to position, reset origin, run code.

this however leaves the z-axis at zero work co-ords but -50 machine co-ords.

the next time i issue a start cycle i get soft limit warning on Z axis as i am trying to probe to -65mm from machine zero but it obviously wont let me as that would be way beyond machine z limit max.

is there a way round this????
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives.
Plasma table, Mach3 V062, Step motors, C&CNC THC.

Offline Hood

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Re: Soft limits info please...
« Reply #1 on: February 17, 2014, 04:57:22 AM »
You need to home the machine on startup and have the SoftLimits correct. The Z will likely be Zero as Max and the travel of your Z axis as the Min setting, but as a negative value.
You get the soft limits setup from Config menu then Homing and Limits.
Hood

Offline Davek0974

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Re: Soft limits info please...
« Reply #2 on: February 17, 2014, 05:18:23 AM »
Yeah, thats all done and understood.

I just ran one part, it left the z axis at -95, when i went to repeat the run it faulted on z-axis soft limit.

Z soft is set at -75/0 as that is the physical limits.

I think i'm getting in a state with work offsets or something lingering at the end of each run that i need to reset??

dont forget i'm using G31 probing.
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives.
Plasma table, Mach3 V062, Step motors, C&CNC THC.

Offline Hood

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Re: Soft limits info please...
« Reply #3 on: February 17, 2014, 05:28:01 AM »
soft limits are machine coords so as long as you are homing the correct direction and have the soft limits set to axis travels then it should be fine no matter what the work offsets are.
If however you are homing fully down then you will either need to set the Z Min as Zero and Max as travel as a positive value or better would be set a Home Off value to the Homing and Limits setting for the Z, that value would be the travel of your axis as a negative value.

So basically it all depends where your Z homes to and also make sure your Z is travelling the correct way, ie Z negative motion is down.
Hood

Offline Davek0974

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Re: Soft limits info please...
« Reply #4 on: February 17, 2014, 05:34:35 AM »
Yes z home is at the top and works ok,

The part i run left z at 10 which is the park setting in the post processor.

I have mach set to issue a g92.1 reset at the end of each run.

the run left the z dro at -95 with a work offset.

When i go to run again i get z soft warning.

If i re-home, all is well but only for one run, i cant run more than one cycle without rehoming??????

something is not set right but i fail to see what.

Z max is zero and min is -75 as it homes at the top.
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives.
Plasma table, Mach3 V062, Step motors, C&CNC THC.

Offline Davek0974

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Re: Soft limits info please...
« Reply #5 on: February 17, 2014, 06:29:56 AM »
Could someone have a scan of the simple .tap file attached please.

I am trying to learn why it throws a soft-Z limit upon cycle start.

Z max = 0
Z min = -75
Homed to top position.

I can run the part but not without acknowledging the warning first

thanks
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives.
Plasma table, Mach3 V062, Step motors, C&CNC THC.

Offline Hood

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Re: Soft limits info please...
« Reply #6 on: February 17, 2014, 07:08:57 AM »
Not had a chance to look through the code but it is likely the G31 that is making Mach think the motion will go outwith the limits. Might want to try an older version of Mach if you are currently using 066 as that may also be an issue.
Hood

Offline Davek0974

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Re: Soft limits info please...
« Reply #7 on: February 17, 2014, 07:14:00 AM »
Oh dear.

How do i get an older version and will it upset the work you did on the screen set???


Dave
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives.
Plasma table, Mach3 V062, Step motors, C&CNC THC.

Offline Davek0974

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Re: Soft limits info please...
« Reply #8 on: February 17, 2014, 07:50:54 AM »
Is there really an issue with probing/offsets in v066??

How can i probe in another way that works??

I was finally hoping to get my machine cutting this week for the first time but I am having serious issues with z soft limits and my code.

Is it easy to downgrade and where do i find older versions? Google brings up nothing.

Will it upset the custom screenset & xml i have?


I'm losing the faith :(
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives.
Plasma table, Mach3 V062, Step motors, C&CNC THC.

Offline Hood

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Re: Soft limits info please...
« Reply #9 on: February 17, 2014, 08:04:19 AM »
I dont know if 066 has issues with probing, I do know it has issues with homing if using an external controller and also issues with Lathes and I have heard of a few others.
 You can get older versions from here ftp://anonymous@machsupport.com/

As I said I have not had a chance to go through your code with your xml, bit busy at work today so will be tonight at the earliest before I can spend time.

Hood