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    Solved The back off might not be proper in relative position.

    Tuning and tweaking
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    • mendelevium
      mendelevium last edited by

      Error: Bad command: this home all script has to be rethought when the printer is commissioned. The back off might not be proper in relative position.
      I get this error 6 times (repeated 6 times when my printer does homing) I see nothing inappropriate. Any suggestions please? see my homing script....
      many thanks in advance.

      G91 ;relative mode
      G1 Z275 F2000 H1 ; move Z rapidly / 300mm up/ until Homing is triggered
      G90 ;absolute mode
      G1 Z260 F100 ; retract z 3mm slowly
      G91 ;relative mode
      G1 Z5 F25 H1 ; re-home at slow speed
      G90 ; return to absolute mode
      G1 Z261 ; back off

      G91 ;relative mode
      G1 Y400 F1000 H1 ; move Y rapidly / 300mm up/ until Homing is triggered
      G90 ; return to absolute mode
      G1 Y299 F100 ; retract Y 3mm slowly
      G91 ;relative mode
      G1 Y10 F25 H1 ; re-home at slow speed
      G90 ; return to absolute mode
      G1 Y300 ; back off reference at absolute

      G91 ;relative mode
      G1 X500 F1000 H1 ; move X rapidly / 300mm up/ until Homing is triggered
      G90 ; return to absolute mode
      G1 X344 F100 ; retract X 3mm slowly
      G91 ;relative mode
      G1 X10 F25 H1 ; re-home at slow speed
      G90 ; return to absolute mode
      G1 X344 ; back off reference at absolute

      SIam fcwilt dc42 3 Replies Last reply Reply Quote 0
      • SIam
        SIam @mendelevium last edited by

        @mendelevium can you provide the complete error message? What happens when you enter the in console: M98 P"name of the above script"

        Hypercube-Evolution-Hybrid, Piezo Orion, Orbiter
        Duet WiFi 1.02 or later + DueX5
        RepRapFirmware for Duet 2 WiFi/Ethernet 3.4.0beta4 (2021-09-27 11:30:36)
        Duet WiFi Server: 1.26
        Duet Web Control 3.4.0beta4 (2021-09-27)

        mendelevium 1 Reply Last reply Reply Quote 0
        • fcwilt
          fcwilt @mendelevium last edited by

          @mendelevium

          Typically the homing procedure involves 3 relative moves.

          1st - "fast" toward the endstop sensor until it is triggered.
          2nd - back off a short distance - often at the same speed.
          3rd - "slow" toward the endstop sensor until it is triggered.

          You are switching to absolute for move 2 - why are you doing that?

          Your 4th move for each axis has no F parameter and is going to be done at F25 which is quite slow - is that what you want?

          Thanks.

          Frederick

          Printers: A FT-5 with the 713 upgrade bits. A custom MarkForged style. A small Utilmaker style and a CoreXY from kits. Various hotends. Using Duets (2 and 3) running 3.4.1

          mendelevium 1 Reply Last reply Reply Quote 0
          • mendelevium
            mendelevium @SIam last edited by

            @siam
            The exact script is this;-

            mendelevium
            mendelevium
            6 Jun 2021, 12:15

            Error: Bad command: this home all script has to be rethought when the printer is commissioned. The back off might not be proper in relative position.

            1 Reply Last reply Reply Quote 0
            • mendelevium
              mendelevium @fcwilt last edited by

              @fcwilt
              That is exactly what I am doing. when I hit the end-stop a second time slowly - to be more precise.
              then I back off away from the microswitch. The second back-off speed makes any difference? I decided to use absolute since the position is then accurate. I do not know if it makes a difference. At work I deal with a number of CNC machine tools- lathes, machining centers and others.. that is how they behave.

              fcwilt 1 Reply Last reply Reply Quote 0
              • fcwilt
                fcwilt @mendelevium last edited by

                @mendelevium said in The back off might not be proper in relative position.:

                @fcwilt
                That is exactly what I am doing. when I hit the end-stop a second time slowly - to be more precise.
                then I back off away from the microswitch. The second back-off speed makes any difference? I decided to use absolute since the position is then accurate. I do not know if it makes a difference. At work I deal with a number of CNC machine tools- lathes, machining centers and others.. that is how they behave.

                Well as I said "typically" all three moves are relative.

                And you are getting an error message mentioning "back off" and "relative".

                If it were me I would just make all three moves relative and see if that makes the error message go away.

                There is no advantage to having the 2nd move be absolute and it complicates the code a bit.

                The speed of each move is up to you. It's fine to use the same speed for both the 1st and 2nd moves but, as you have done, the 3rd move is typically at a slower speed.

                But you likely want the 4th move to be at a speed faster then F25.

                Printers: A FT-5 with the 713 upgrade bits. A custom MarkForged style. A small Utilmaker style and a CoreXY from kits. Various hotends. Using Duets (2 and 3) running 3.4.1

                mendelevium 1 Reply Last reply Reply Quote 0
                • dc42
                  dc42 administrators @mendelevium last edited by

                  @mendelevium said in The back off might not be proper in relative position.:

                  Error: Bad command: this home all script has to be rethought when the printer is commissioned. The back off might not be proper in relative position.

                  That message must be either in your homeall.g file or in homex.g, homey.g and homez.g. It is not generated by the firmware

                  Duet WiFi hardware designer and firmware engineer
                  Please do not ask me for Duet support via PM or email, use the forum
                  http://www.escher3d.com, https://miscsolutions.wordpress.com

                  mendelevium 1 Reply Last reply Reply Quote 1
                  • mendelevium
                    mendelevium @dc42 last edited by

                    @dc42
                    you mean the error is being generated by an improperly scripted homeall/homex/y/z right?
                    the homeall has all the three files scripts in it.

                    dc42 1 Reply Last reply Reply Quote 0
                    • mendelevium
                      mendelevium @fcwilt last edited by

                      @fcwilt
                      nothing to loose by trying your suggestion...

                      1 Reply Last reply Reply Quote 0
                      • dc42
                        dc42 administrators @mendelevium last edited by

                        @mendelevium said in The back off might not be proper in relative position.:

                        @dc42
                        you mean the error is being generated by an improperly scripted homeall/homex/y/z right?
                        the homeall has all the three files scripts in it.

                        Yes. Please post the entire homeall.g file exactly as it is, also homex.g, homey.g, homez.g. Most likely, someone put those messages in the file(s) but they are not preceded by ';' so they are treated as commands instead of comments.

                        Duet WiFi hardware designer and firmware engineer
                        Please do not ask me for Duet support via PM or email, use the forum
                        http://www.escher3d.com, https://miscsolutions.wordpress.com

                        mendelevium 2 Replies Last reply Reply Quote 1
                        • mendelevium
                          mendelevium @dc42 last edited by

                          @dc42
                          Hmmm
                          the homeall has that. But funnily enough it is appears 6 times....

                          this home all script has to be rethought when the printer is commissioned. The back off might not be proper in relative position.

                          G91 ;relative mode
                          G1 Z275 F2000 H1 ; move Z rapidly / 300mm up/ until Homing is triggered
                          G90 ;absolute mode
                          G1 Z260 F100 ; retract z 3mm slowly
                          G91 ;relative mode
                          G1 Z5 F25 H1 ; re-home at slow speed
                          G90 ; return to absolute mode
                          G1 Z261 ; back off

                          G91 ;relative mode
                          G1 Y400 F1000 H1 ; move Y rapidly / 300mm up/ until Homing is triggered
                          G90 ; return to absolute mode
                          G1 Y299 F100 ; retract Y 3mm slowly
                          G91 ;relative mode
                          G1 Y10 F25 H1 ; re-home at slow speed
                          G90 ; return to absolute mode
                          G1 Y300 ; back off reference at absolute

                          G91 ;relative mode
                          G1 X500 F1000 H1 ; move X rapidly / 300mm up/ until Homing is triggered
                          G90 ; return to absolute mode
                          G1 X344 F100 ; retract X 3mm slowly
                          G91 ;relative mode
                          G1 X10 F25 H1 ; re-home at slow speed
                          G90 ; return to absolute mode
                          G1 X344 ; back off reference at absolute

                          ; homez.g
                          ; called to home the Z axis
                          ; Created by Tonio 28feb 2021
                          G91 ;relative mode
                          G1 Z275 F2000 H1 ; move Z rapidly / 300mm up/ until Homing is triggered
                          G90 ;absolute mode
                          G1 Z260 F100 ; retract z 3mm slowly
                          G91 ;relative mode
                          G1 Z5 F25 H1 ; re-home at slow speed
                          G90 ; return to absolute mode
                          G1 Z261 ; back off

                          ; homey.g
                          ; called to home the Y axis
                          ;
                          ; Created by Tonio 28feb 2021
                          G91 ;relative mode
                          G1 Y400 F1000 H1 ; move Y rapidly / 300mm up/ until Homing is triggered
                          G90 ; return to absolute mode
                          G1 Y299 F100 ; retract Y 3mm slowly
                          G91 ;relative mode
                          G1 Y10 F25 H1 ; re-home at slow speed
                          G90 ; return to absolute mode
                          G1 Y300 ; back off reference at absolute

                          ; homex.g
                          ; called to home the X axis
                          ;
                          ; Created by Tonio 28feb 2021
                          G91 ;relative mode
                          G1 X500 F1000 H1 ; move X rapidly / 300mm up/ until Homing is triggered
                          G90 ; return to absolute mode
                          G1 X344 F100 ; retract X 3mm slowly
                          G91 ;relative mode
                          G1 X10 F25 H1 ; re-home at slow speed
                          G90 ; return to absolute mode
                          G1 X344 ; back off reference at absolute

                          1 Reply Last reply Reply Quote 0
                          • mendelevium
                            mendelevium @dc42 last edited by

                            @dc42
                            took off that comment and the error vanished... thanks so much
                            the matter is closed..

                            1 Reply Last reply Reply Quote 1
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