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  1. #1
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    Nov 2010
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    Homing with physical switches

    When i do Homing using physical switches, everything goes well except the DRO for the machine coordinates is not showing zero but it shows positive number for x and y and a negative number for the Z axis It should show zero for all 3 DRO. The AUTO ZEROS in Homing Limits are already ticked. What's wrong?

    But if I use Soft Limits to Ref All Home, the machine coordinate are all zeros for X Y and Z.

  2. #2
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    Re: Homing with physical switches

    In the homing config in Mach3, there are entries for the X Y Z home position that the DROs will be set to when the switch is hit.
    Check their value and set them to Zero.

    Cheers

    Peter


    Sent from my iPhone using Tapatalk Pro
    -------------------------------------------------
    Homann Designs - http://www.homanndesigns.com/store

  3. #3
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    Is G28 Home location coordinates you are referring to?It's all zeros when the problem happens.
    Quote Originally Posted by phomann View Post
    In the homing config in Mach3, there are entries for the X Y Z home position that the DROs will be set to when the switch is hit.
    Check their value and set them to Zero.

    Cheers

    Peter


    Sent from my iPhone using Tapatalk Pro

  4. #4
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    Dec 2012
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    Re: Homing with physical switches

    Hello.

    It is possible that you have to do either a manual zeroing or a MOVE to coordinates <0,0,0>.

    Another possibility is as follows.

    I´m not familiar with software other than my own yet it is possible that your system is adding some takeoff distance that you have not considered. Let me explain.

    In my machines once I run the HOME sequence all the motors are driven in that direction. Every axis stops when its corresponding home sensor is hit. Once all home sensors are pressed another sequence turns the motors for a given distance away from each sensor. I named that distance as TAKEOFF. I don´t know if it´s named differently or even exists on other systems. I can preset that distance. It´s not until all axes have reached that distance that the counters are reset to zero.

    I hope this helps.

    Regards.

  5. #5
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    Re: Homing with physical switches

    Quote Originally Posted by BBMNet View Post
    In my machines once I run the HOME sequence all the motors are driven in that direction. Every axis stops when its corresponding home sensor is hit. Once all home sensors are pressed another sequence turns the motors for a given distance away from each sensor. I named that distance as TAKEOFF. I don´t know if it´s named differently or even exists on other systems. I can preset that distance. It´s not until all axes have reached that distance that the counters are reset to zero.
    I think that's normally referred to as "back-off"
    All controllers have their own homing routines but it's not uncommon to approach homing sensors at speed and then slowly back-off again until the sensors are cleared to get an accurate position.

    I suspect that the configuration lazercut is looking for is in the controller configuration.

  6. #6
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    And where is this aetting hidden? Thanks
    Quote Originally Posted by hof View Post
    I think that's normally referred to as "back-off"
    All controllers have their own homing routines but it's not uncommon to approach homing sensors at speed and then slowly back-off again until the sensors are cleared to get an accurate position.

    I suspect that the configuration lazercut is looking for is in the controller configuration.

  7. #7
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    Re: Homing with physical switches

    I'm not familiar with Mach3 which I guess that you are using. Perhaps it's integrated with the other settings.
    In Mach4 it's under config > control and the configuration looks different for each controller plug-in.
    Perhaps someone with Mach3 experience can step in?

  8. #8
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    I am sure one day that setting will be discovered.
    Soft limits is good enough for now. The physical switches will double up as limit switches.
    Quote Originally Posted by hof View Post
    I'm not familiar with Mach3 which I guess that you are using. Perhaps it's integrated with the other settings.
    In Mach4 it's under config > control and the configuration looks different for each controller plug-in.
    Perhaps someone with Mach3 experience can step in?

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