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    Problem with z-probe offset

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    • fcwiltundefined
      fcwilt
      last edited by

      @koaldesigns said in Problem with z-probe offset:

      This is invalid - delete it - or comment it out: M574 Z1 S2 ; configure Z-probe endstop for low end on Z

      This serves no purpose - do that same as above: M574 Z0 P"nil" ; no Z endstop switch, free up Z endstop input

      You have no X and Y offset values in this: G31 P500 Z2.41

      To be safe add them: G31 P500 Xnnn Ynnn Z2.41 where nnnn are the actual values for your printer.

      I have never encountered any situation where the Z offset value is simply ignored.

      Why do you think it is being ignored?

      Frederick

      Printers: a small Utilmaker style, a small CoreXY and a E3D MS/TC setup. Various hotends. Using Duet 3 hardware running 3.4.6

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      • koaldesignsundefined
        koaldesigns
        last edited by

        @fcwilt I have modified my config.g to what you suggested:

        ;Endstops
        
        M574 X1 S1 P"!xstop"   ; X min active low endstop switch
        M574 Y1 S1 P"!ystop"   ; Y min active low endstop switch
        M574 Z1 S0             ; configure Z-probe endstop for low end on Z
        
        ;Z-Probe
        
        M558 P1 C"zprobe.in" H18 F200 R.5 T3600 # Z-Probe connected to Z-endstop input
        G31 P500 X1 Y1 Z2.41
        M557 X150:600 Y-450:450 S50 ; probe from X=10 to 190, Y=10 to 190mm with a mesh spacing of 20mm
        

        I have tested this and the offset is still .7mm even though it is defined as 2.41mm. I have changed the dive height (H) and after homing it is always the dive height (H) +0.7mm instead of H + 2.41mm so the trigger height is definitely being ignored.

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

          @koaldesigns

          Odd.

          Please post your homeALL.g and homeZ.g files

          Frederick

          Printers: a small Utilmaker style, a small CoreXY and a E3D MS/TC setup. Various hotends. Using Duet 3 hardware running 3.4.6

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          • koaldesignsundefined
            koaldesigns
            last edited by

            I do not have a home.z files as it is impossible for my printer to only home the Z-axis as it is dependent on the other axis being homed. My homeall.g is as follows:

            G91							;Relative positioning
            M561					;Remove any mesh leveling
            G92 W0					;Set Z to 0 (temporary no z stop yet)
            
            G1 H2 Z30 F400
            G0 H1 Y-300 X-300 F800		;Move both distal and proximal to home positions
            G0 H2 X5 F200				;Slowly turn proximal away from home position
            G0 H1 X-10 F200				;Slowly home proximal
            G0 H2 Y5 F200				;Slowly turn distal away from home position
            G0 H1 Y-10 F200				;Slowly home distal
            
            G90							;Absolute positioning
            
            G0 H2 X-60 Y60 W0 F800			;Move arm to center of range
            G30
            

            @fcwilt

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

              @koaldesigns

              I don't think you need the H2 parameters on the X and Y moves.

              Everything else looks fine.

              When you say it ends up at dive height + 0.7mm - is that as reported by the DWC or are you measuring it?

              Thanks.

              Frederick

              Printers: a small Utilmaker style, a small CoreXY and a E3D MS/TC setup. Various hotends. Using Duet 3 hardware running 3.4.6

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              • koaldesignsundefined
                koaldesigns
                last edited by

                I do need the H2 parameters because it's a SCARA machine. Everything has been tuned and works properly for what I need except the z offset. Also, I don't have to measure it because that's what the firmware says, and when I move to Z0, the hotend is always the same distance above the bed no matter the z-offset so it is being ignored. @fcwilt

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

                  @koaldesigns

                  Have you executed a G31 from the console after booting to see what it reports?

                  You don't by chance have another G31 somewhere this overriding the one in config.g?

                  Frederick

                  Printers: a small Utilmaker style, a small CoreXY and a E3D MS/TC setup. Various hotends. Using Duet 3 hardware running 3.4.6

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                  • koaldesignsundefined
                    koaldesigns
                    last edited by

                    The G31 command yielded this before and after homing:

                    G31
                    Z probe 0: current reading 487, threshold 500, trigger height 2.410, offsets X1.0 Y1.0
                    

                    but still reports 18.7mm z height after homing when it should be 20.41. @fcwilt

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

                      @koaldesigns said in Problem with z-probe offset:

                      The G31 command yielded this before and after homing:

                      G31
                      Z probe 0: current reading 487, threshold 500, trigger height 2.410, offsets X1.0 Y1.0
                      

                      but still reports 18.7mm z height after homing when it should be 20.41. @fcwilt

                      What kind of probe is it?

                      That reading of 487 is awfully close to the threshold value.

                      I noticed that in your homeALL.g file you used G92 W0 with the comment that there was no Z end stop yet.

                      It got me to thinking. Does your printer have a axis named Z? If not how does G30 know to move on W.

                      Curious.

                      The only other thing I can think of is that 3.2 has a bug. I know for my printer with 3 Z steppers each with their own Z end stop switch there was a bug that prevented it from working correctly.

                      Frederick

                      Printers: a small Utilmaker style, a small CoreXY and a E3D MS/TC setup. Various hotends. Using Duet 3 hardware running 3.4.6

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                      • koaldesignsundefined
                        koaldesigns
                        last edited by

                        The W axis is a wrist joint and is irrelevant for this. I'm going to give it a break for tonight and see whats up tomorrow. It could be something to due with mesh bed leveling but I'm unsure. @fcwilt

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                        • Phaedruxundefined
                          Phaedrux Moderator
                          last edited by

                          Do you get any errors when sending M98 P"config.g"?

                          Z-Bot CoreXY Build | Thingiverse Profile

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                          • chas2706undefined
                            chas2706
                            last edited by

                            Sorry to hijack this thread but would just like to get something off my chest.
                            Ive had problems with both my corexy printers regarding Z height and first layer issues since upgrading from RRF3.1.1. Both printers have SBC. They both now running on RRF3.2.2 and neither are capable of printing anything from scratch without my intervention. Each time I have to adjust babystepping to get the first layer height correct.
                            Example: In config.g one printer has Z offset G31 X-30 Y-5 Z2.72 which was found by doing correct process to find Z height. On attempting to print, Z is too high. If I lower Z by 0.28 using on the fly babystepping the first layer is spot on. Before next print I change G31 in config.g to G31 X-30 Y-5 Z3.0 so as to equal the difference with babystep. On next print Z is too low and babystepping back up by 0.28 corrects this!!!!
                            Just in case I'm doing something wrong I then change config to G31 X-30 Y-5 Z2.44 (minus 0.28). This time the print too low by 0.28!!!
                            Both printers have similar issue and neither printer has any other G31 command in any other piece of gcode or macro.
                            I have only one functional printer which is old faithful ender 3 pro which in my opinion prints every time because there's no Z probe present, everything is set up manually, no SBC attached and therefore much simpler.
                            Ever since RRF3 firmware versions have been available I've had issues and still have issues with SBC not always connecting to DCS, when booted up, sometimes config.g not been processed so DWC shows no extruders, no heaters, no fans etc...
                            It was months and months ago that i first reported an issue that any gcode command that I enter into the console in DWC has to be clicked on twice before DWC responds, I find that this issue is STILL present and has now even expanded to include the emergency stop icon on DWC. So at one point my head crashed into the bed because the emergency stop does not always work first time!!!
                            Lastly, I fail to understand how on both printers with SBC attached i often encounter "network failed, no network connection" showing on SBC's DWC but im somehow happily connected to DWC via laptop!!
                            I spent £1500 on my last printer but the best and most reliable prints come from my simple £250 Ender 3.
                            Rant over, feel better now!

                            Phaedruxundefined 1 Reply Last reply Reply Quote 1
                            • Phaedruxundefined
                              Phaedrux Moderator @chas2706
                              last edited by

                              @chas2706 said in Problem with z-probe offset:

                              Rant over, feel better now!

                              Well that's something at least. 😉 Feel free to start a new thread if you want to work through any other issues.

                              Z-Bot CoreXY Build | Thingiverse Profile

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                              • chas2706undefined
                                chas2706
                                last edited by

                                Sorry to hijack this thread but would just like to get something off my chest.
                                Ive had problems with both my corexy printers regarding Z height and first layer issues since upgrading from RRF3.1.1. Both printers have SBC. They both now running on RRF3.2.2 and neither are capable of printing anything from scratch without my intervention. Each time I have to adjust babystepping to get the first layer height correct.
                                Example: In config.g one printer has Z offset G31 X-30 Y-5 Z2.72 which was found by doing correct process to find Z height. On attempting to print, Z is too high. If I lower Z by 0.28 using on the fly babystepping the first layer is spot on. Before next print I change G31 in config.g to G31 X-30 Y-5 Z3.0 so as to equal the difference with babystep. On next print Z is too low and babystepping back up by 0.28 corrects this!!!!
                                Just in case I'm doing something wrong I then change config to G31 X-30 Y-5 Z2.44 (minus 0.28). This time the print too low by 0.28!!!
                                Both printers have similar issue and neither printer has any other G31 command in any other piece of gcode or macro.
                                I have only one functional printer which is old faithful ender 3 pro which in my opinion prints every time because there's no Z probe present, everything is set up manually, no SBC attached and therefore much simpler.
                                Ever since RRF3 firmware versions have been available I've had issues and still have issues with SBC not always connecting to DCS, when booted up, sometimes config.g not been processed so DWC shows no extruders, no heaters, no fans etc...
                                It was months and months ago that i first reported an issue that any gcode command that I enter into the console in DWC has to be clicked on twice before DWC responds, I find that this issue is STILL present and has now even expanded to include the emergency stop icon on DWC. So at one point my head crashed into the bed because the emergency stop does not always work first time!!!
                                Lastly, I fail to understand how on both printers with SBC attached i often encounter "network failed, no network connection" showing on SBC's DWC but im somehow happily connected to DWC via laptop!!
                                I spent £1500 on my last printer but the best and most reliable prints come from my simple £250 Ender 3.
                                R

                                Phil Maddoxundefined 2 Replies Last reply Reply Quote 1
                                • Phil Maddoxundefined
                                  Phil Maddox @chas2706
                                  last edited by Phil Maddox

                                  @chas2706 Im experiencing pretty much the same behavior . I need 0.280 in baby stepping to even get the print on the bed

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                                  • Phil Maddoxundefined
                                    Phil Maddox @chas2706
                                    last edited by

                                    @chas2706 Updated to 3.2.2 and removed a space i had before the Z numerical field in config.g and my problems have gone away
                                    Good luck

                                    1 Reply Last reply Reply Quote 1
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