When starting print (I have a piezo sensor) it starts print at 0

I have successfully added the piezo sensor to my dbot with a duetwifi.

Problem I have is that now, when starting the print, it is at 0 and does not move up to .3 even though I have it at .3 in cura. I have no idea why it is not moving up to the initial height.

Any thoughts? I am pretty confused as to why it won't sent the initial layer hieight even though zprobe height is 0.

Config.g

; CoreXY sample config file for dc42 Duet firmware by Haga. Please use with care. Some of the settings needs to be changed to work with your printer. Read the duetWiki!
;*** [duet3d.com]

; Communication and general
M111 S0                             ; Debug off
M550 PDBotCoreXY                    ; Machine name (P + anything you like)
M551 Preprap                        ; Machine password (used for FTP connections)
M540 P0xBE:0xEF:0xDE:0xAD:0xFE:0xED ; MAC Address - If you have more than one Duet on your network, they must all have different MAC addresses, so change the last digits
M552 S1           					; Enable WiFi
M555 P2                             ; Set output to look like Marlin
;M575 P1 B57600 S1                  ; Comms parameters for PanelDue
M667 S1                    			; set CoreXY mode

; Machine configuration
M569 P0 S0               			; Drive 0 goes forwards (change to S0 to reverse it)
M569 P1 S1              			; Drive 1 goes forwards. (Change if motor goes wrong way. Or just turn the motor connection 180 degrees around..) 
M569 P2 S0                			; Drive 2 goes forwards z
M569 P3 S1                			; Drive 3 goes forwards 0
M569 P4 S1                			; Drive 4 goes forwards

M574 X1 Y2 S0            			; set endstop configuration (X1 is at MIN end. Y2 is at MAX end. (active high switch = S1, active low switch= S0)
M574 Z2 S1            				; set endstop configuration (X1 is at MIN end. Y2 is at MAX end. (active high switch = S1, active low switch= S0)



M350 X16 Y16 Z16 E16 I1             ; Set 16x microstepping with interpolation

M92 X100 Y100 Z800            		; Set axis steps/mm. Check that the printer really move as much as you tell it. Not more and not less.
M92 E138.4:138.4            		; Set extruder steps/mm. Change this to match your extruder.

M906 X800 Y800 Z800 E800            ; Set motor currents (mA). Increase if motor is to weak. Lower if motor gets too hot. 800-1000 is good for most.

M201 X1500 Y1500 Z300 E4000         ; Accelerations (mm/s^2). The acceleration, speed and jerk is a setting you can alter to try making the printer to print as nice as possible.. 
M203 X15000 Y15000 Z300 E1500       ; Maximum speeds (mm/min)
M566 X600 Y600 Z24 E300             ; Maximum jerk speeds mm/minute

M208 X300 Y200 Z300            		; set axis maxima (adjust to suit your machine)
M208 X0 Y0 Z0 S1                    ; set axis minima (adjust to make X=0 and Y=0 the edges of the bed)

G21                                 ; Work in millimetres
G90                                 ; Send absolute coordinates...
M83                                 ; ...but relative extruder moves

; Z probe
M558 P1 I0 R0.2 F500 X0 Y0 Z1       ; Analog Z probe, also used for homing the Z axis
G31 X0 Y0 Z0.1 P700               ; Set the probe height and threshold (put your own values here)
; The following M557 commands are not needed if you are using a bed.g file to perform bed compensation
;*** Adjust the XY coordinates in the following M557 commands to suit your build and the position of the Z probe
;M557 P0 X15 Y-15                     ; Four... 
;M557 P1 X15 Y-185                    ; ...probe points...
;M557 P2 X285 Y-185                   ; ...for bed...
;M557 P3 X285 Y-15                    ; ...levelling
;M557 P4 X150 Y-100                    ; 5th probe point for levelling

; Thermistors and heaters

;*** You can use S and B parameters to define the parameters of the thermistors you are using. Standard 100k thermistor from E3d is 4388 or 4725.
M305 P0 T100000 B4388 R4700 H0 L0   		; Put your own H and/or L values here to set the bed thermistor ADC correction
M305 P1 T100000 B4388 R4700 H0 L0   		; Put your own H and/or L values here to set the first nozzle thermistor ADC correction
;M305 P2 T100000 B4388 R4700 H0 L0  		; Put your own H and/or L values here to set the second nozzle thermistor ADC correction

;***Choose if you want to use the M301 or the autotune results and M307 command. Don't use both.
M301 H1 P10 I0.10 D100 T0.50 S1.0  		    ;PID settings for extruder 0 (no need for M301 if using M307)
;M301 H2 P10 I0.10 D100 T0.50 S1.0   		;PID settings for extruder 1

M570 S120                					;Increase to allow extra heating time if needed

;***Use for autotune. Comment out M301 if you do.
;M307 H0 A142 C293.5 D5.4 B0 				;Autotune result for bed
;M307 H1 A588.5 C242.9 D6.7 B0				;Autotuen result for first nozzle

; Fans
M106 P1 T45 H1	; enable thermostatic mode for fan 1 at temp 45 degrees. Fan turns on when P1(extruder 1) is above 45 degrees.

; Tool definition
M563 P1 D0 H1                       ; Define tool 0
G10 P1 S0 R0                        ; Set tool 0 operating and standby temperatures

;*** If you have a dual-nozzle build, un-comment the following 3 lines
;M563 P0 D1 H2                      ; Define tool 1
;G10 P0 S0 R0                       ; Set tool 1 operating and standby temperatures

;*** If you are using axis compensation, put the figures in the following command
M556 S78 X0 Y0 Z0                   ; Axis compensation here
M208 S1 Z0			; set minimum Z
M501								; Load Config-Override.g that is created using M500
T0                                  ; select first hot end

;*** Home all
G91

G1 Z10 F2000 		; lowers bed 4mm to avoid dragging nozzle over the bed

G1 X-340 F3000 S1  	; move up to 340/240mm in the -X (x endstop is MIN) and +Y(y endstop is MAX) directions until the homing switches are triggered
G1 X4 F600
G1 X-10 S1

G1 Y240 F3000 S1
G1 Y-4 F600 		; move slowly 4mm in +X and +Y directions
G1 Y10 S1 		; move up to 10mm in the -X and -Y directions until the homing switches are triggered

G91               	; set movement to relative mode
G1 Z5 F200       	; move Z down 5mm
G90               	; set movement to absolute mode
G1 X145 Y100 F2000  	; move X and Y to probe point. ADJUST X and Y values to get Z probe over target.
G30                	; home Z, using values from G31 in config.g
G91 
G1 Z.3 F200        	; move Z to Z=0
G90

T1
T-1
G10 P1 R140
M140 S60

Start Code

G21 ;metric values\n
G90 ;absolute positioning\n
M82 ;set extruder to absolute mode\n
M107 ;start with the fan off\n
G28 X0 Y0 ;move X/Y to min endstops\n
G28 Z0 ;move Z to min endstops\n
G29 S1 ;load mesh\n 
G1 Z15.0 F9000 ;move the platform down 15mm\n
G92 E0 ;zero the extruded length\n
G1 F200 E3 ;extrude 3mm of feed stock\n
G92 E0 ;zero the extruded length again\n
G1 F9000\n;Put printing message on LCD screen\nM117 Printing..."

Homeall.g

;homeall.g
;homing using a x-MIN, Y-MAX and z-MIN endstops



G91

G1 Z10 F2000 		; lowers bed 4mm to avoid dragging nozzle over the bed

G1 X-340 F3000 S1  	; move up to 340/240mm in the -X (x endstop is MIN) and +Y(y endstop is MAX) directions until the homing switches are triggered
G1 X4 F600
G1 X-10 S1

G1 Y240 F3000 S1
G1 Y-4 F600 		; move slowly 4mm in +X and +Y directions
G1 Y10 S1 		; move up to 10mm in the -X and -Y directions until the homing switches are triggered

G91               	; set movement to relative mode
G1 Z5 F200       	; move Z down 5mm
G90               	; set movement to absolute mode
G1 X145 Y100 F2000  	; move X and Y to probe point. ADJUST X and Y values to get Z probe over target.
G30                	; home Z, using values from G31 in config.g

G91 

G1 Z.3 F200        	; move Z to Z=0

G90

What's in the gcode? Sorry, .g is your gcode

Edited 1 time(s). Last edit at 06/17/2017 09:59PM by etfrench.

I am certainly no expert in the duetwifi but perhaps

G1 Z.3 F200 ; move Z to Z=0

should be G1 Z0.3 F200 in your config.g (and homeall.g) ??

It might be your G31 in config.g you have Z0.1 set which tells the system the probe triggers 0.1mm above the bed. It's actually 0.2mm below the bed with Piezo (on average) so change this to Z-0.2 and try again. That's your 0.3mm there.

Once you've probed/calibrated/levelled move to bed centre and send nozzle to z=0 it should be at exactly z=0 now ask for G1 Z0.3 and if you have feeler gauges check that it's 0.3mm if not alter the G31 offset a little.

I'd agree that the G1 z.3 f200 is probably unnecessary.

Edited 3 time(s). Last edit at 06/18/2017 07:42PM by DjDemonD.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Thanks guys. I will give that a go, things seem to be working a little better.

Also. Once I have calibrated and leveled for the first time, do I am not sure what to run and when.

Printer Startup - Do I need to set zero or just home it?
Calibration - done once in a while right and not all the time?
Print Start - Reference mesh and home

I do G30 at bed centre after home x and y. Then raise nozzle 10mm and I do G30 S-1 to check level after.

I do G29 grid level (see duet wiki for define levelling grid) which saves the grid. Load it using G29 S1 in config. I redo it if I change anything mechanically or change bed temp. But I don't do a grid level for each print it's not likely to change.

Any issues with false triggers and you need to include some reduced acceleration/jerk settings for probing, then speed back up after for normal printing.

Edited 3 time(s). Last edit at 06/19/2017 05:35AM by DjDemonD.

---

Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions