Delta z height AC Predator

[Gary]

No z height stays the same, which is my problem!

"I’ve tried using G92 to set z height, but it does not seem to work. Is there any way of setting the z height with a macro?"

[jay_s_uk]

@Gary
I haven't had any issues with the Z height on my predator.
Is it maybe the z probe offset that you have issues with?

[Gary]

Nothing to do with the probe. Switch on and z height different.
01/03/20 - 449.10
01/03/20 - 450.15
02/03/20 - 450.15
07/03/20 - 451.42
09/03/20 - 451.72
09/03/20 - 456.42

Gary

[Gary]

last one incorrect as I was messing with homedelta. Probably 451.42

[jay_s_uk]

@Gary

Any chance you could share your config and config-override files so I can take a look?
Are you using the stock effector and probe?

[Gary]

Jay, Stock effector and probe

CONFIG.G
; Configuration file for Duet WiFi (firmware version 1.21)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v2 on Tue Feb 26 2019 21:31:01 GMT+0000 (Greenwich Mean Time)

; General preferences
G21 ; Work in millimetres
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves
M552 S1 ; connect to WiFi

; Delta Settings
M665 L440 R227 H456.747 B185.0 ; Set delta radius, diagonal rod length, printable radius and homed height
M666 X0 Y0 Z0 A0.00 B0.00 ; Put your endstop adjustments here, or let auto calibration find them

; Network
M550 P"Anycubic Predator2" ; Set machine name
M551 P""
M552 P192.168.0.12 ; Set password
;M552 P0.0.0.0 S1 ; Enable network and acquire dynamic address via DHCP
M586 P0 S1 ; Enable HTTP
M586 P1 S0 ; Disable FTP
M586 P2 S0 ; Disable Telnet

; Drives
M569 P0 S0 ; Drive 0 goes forwards
M569 P1 S0 ; Drive 1 goes forwards
M569 P2 S0 ; Drive 2 goes forwards
M569 P3 S1 ; Drive 3 goes forwards (E3D Titan extruder - MT-1703HSM168RE 0.9deg step 180917 1.68A)
M350 X16 Y16 Z16 E16 I1 ; Configure microstepping with interpolation (20teeth pulley) "E3D MT-1704HSM168RE 0.9deg step 190102, 400 steps/rev 1.68A"
M92 X160.00 Y160.00 Z160.00 E837 ; Set steps per mm
M566 X1000 Y1000 Z1000 E1000 ; Set maximum instantaneous speed changes (mm/min)
M203 X12000.00 Y12000.00 Z12000.00 E10000 ; Set maximum speeds (mm/min)
M201 X3000.00 Y3000.00 Z3000.00 E3000.00 ; Set accelerations (mm/s^2)
M906 X1000.00 Y1000.00 Z1000.00 E1100.00 I30 ; Set motor currents (mA) and motor idle factor in per cent
;M906 X1344.00 Y1344.00 Z1344.00 E1344.00 I30 ; Set motor currents (mA) and motor idle factor in per cent (reduced to 80% of max Amps)
;M84 S30 ; Set idle timeout
M84 S600

; Retraction
M207 S4.0 F5000 R-0.025 T2500 Z0.5 ; Firmware retraction

; Axis Limits
M208 Z0 S1 ; Set minimum Z

; Endstops
M574 X2 Y2 Z2 S1 ; Set active high endstops

; Z-Probe (standard AC Predator microswitch probe, clips just under nozzle)
M558 P4 H5 F120 T6000 ; Set Z probe type to switch(P4) and the dive height + speeds
G31 P500 X0 Y0 Z17.656 ; Set Z probe trigger value, offset and trigger height
M557 R115 S20
G29 S1 ; Load the heightmap

; Heaters
M307 H0 A137.8 C533.3 D1.5 V24.3 B0 ; Disable bang-bang mode for the bed heater and set PWM limit
M305 P0 T100000 B4300 C0 R4700 ; Set thermistor + ADC parameters for heater 0
M143 H0 S120 ; Set temperature limit for heater 0 to 120C
M305 P1 T100000 B4300 C0 R4700 ; Set thermistor + ADC parameters for heater 1
M143 H1 S240 ; Set temperature limit for heater 1 to 240C

; Fans
M106 P0 S0 I0 F500 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P1 S1 I0 F500 H1 T45 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on

; Tools for p0
M563 P0 D0 H1 ; Define tool 0
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C

; Automatic saving after power loss is not enabled

; Custom settings are not configured
M572 D0 S0.1 ; Pressure Advance
;M591 D0 P2 C4 S1 ; Activate filament sensor
M404 N1.75 ; Set for print monitor
M592 D0 A0.07772 B-0.00029 ; Nonlinear extrusion. Set parameters for extruder drive 0

; Miscellaneous
T0 ;select tool 0 gary added
M501 ; Load saved parameters from non-volatile memory

CONFIG OVERRIDE
; config-override.g file generated in response to M500 at 2020-03-07 11:46
; This is a system-generated file - do not edit
; Delta parameters
M665 L440.000:440.000:440.000 R224.891 H456.513 B185.0 X-0.442 Y-0.213 Z0.000
M666 X-6.790 Y3.376 Z3.414 A0.00 B0.00
; Heater model parameters
M307 H0 A137.8 C533.3 D1.5 S1.00 V24.3 B0
M307 H1 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H2 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H3 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H4 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H5 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H6 A340.0 C140.0 D5.5 S1.00 V0.0 B0
M307 H7 A340.0 C140.0 D5.5 S1.00 V0.0 B0
G10 L2 P1 X0.00 Y0.00 Z0.00
G10 L2 P2 X0.00 Y0.00 Z0.00
G10 L2 P3 X0.00 Y0.00 Z0.00
G10 L2 P4 X0.00 Y0.00 Z0.00
G10 L2 P5 X0.00 Y0.00 Z0.00
G10 L2 P6 X0.00 Y0.00 Z0.00
G10 L2 P7 X0.00 Y0.00 Z0.00
G10 L2 P8 X0.00 Y0.00 Z0.00
G10 L2 P9 X0.00 Y0.00 Z0.00

Gary

[jay_s_uk]

@Gary
~456mm was roughly what I got when I had mine set up with the stock effector and probe.
Are you sure that the probe is firmly connected to the magnetic plate every time?
Also, are you probing the height every time that you use the machine?

On another note, I would up the current on your M906 command to 1400. I had mine set at 1000 for ages but after receiving info from anycubic, the motors used are 1800ma.

[Gary]

Jay,
Probe not the problem. Turn machine on home and one day z height reads different on another day.
(As above my motors are MT-1704HSM168RE 0.9deg step 190102, 400 steps/rev 1.68A not stock).
On my other stock machine I've set v-ref to 0.61 working great.
Going to change my belts. I've got some GT ones.
Gary

[jay_s_uk]

@Gary
Missed that on the motors.

I never used to probe the machine every time. Couldn't be bothered to fit the probe every time.

I have had a belt snap that appears to have been stretching for a while that led to dodgy readings. If you're going to change the belts, also plan on changing the bottom pulleys as they are smooth and ideally you want toothed pulleys.

Other than that, I've not had an issue with any of the opto endstops etc.

[Gary]

@jay_s_uk
Thanks for your advice. Yeah when problems happen I clean the bed, check the carriages and if that does not work do the stock probe bit. Machine is second hand so who knows what it's been through! Do you have a link to toothed pulleys? I was thinking of getting them. The Gates belts are compatible with the stock belts.
Thanks again
Gary

[jay_s_uk]

@Gary

These are the type you'd need.

[Gary]

@jay_s_uk
Thanks for the link.

I still don't understand how config override has H456.513 as below
M665 L440.000:440.000:440.000 R224.891 H456.513 B185.0 X-0.442 Y-0.213 Z0.000

And doing a Homdelta, (with it being edited to just home), the web interface shows z 456.42. Am I missing something?

[jay_s_uk]

@Gary
Whats in your homedelta file?
Are you doing the home after any sort of probing or is this as soon as the machine is turned on?

[Gary]

@jay_s_uk
Soon as printer turned on. No probing. There's stuff edited out in there that needs deleting, but Homedelta below;

; homedelta.g
; called to home all towers on a delta printer
;
; generated by RepRapFirmware Configuration Tool v2 on Tue Feb 26 2019 21:31:01 GMT+0000 (Greenwich Mean Time)

G91 ; relative positioning

G1 S1 X490 Y490 Z490 F1800 ; move all towers to the high end stopping at the endstops(S1 checks for endstops) (first pass)
;G92 X0 Y0 ;force this to read 0,0
;G92 Z456.747

;below 3 comment/uncomment
;G1 X-5 Y-5 Z-5 F1800 S2 ; go down a few mm GARYuncomment (S2 - Ignore endstops while moving. Also ignore if axis has not been homed.)
;G1 S1 X10 Y10 Z10 F360 ; move all towers up once more (second pass) GARYuncomment
;G1 Z-5 F6000 ; move down a few mm so that the nozzle can be centred GARYuncomment

;G1 Z-10 F1800 ;need to move down for x0 y0 to complete
;G92 Z456.747

G90 ; absolute positioning

;G1 X0 Y0 F1800 ;force to centre
;G92 Z456.747

[Gary]

Normal Homedelta below
Below obviously moves z height. It becomes 441.42

; homedelta.g
; called to home all towers on a delta printer
;
; generated by RepRapFirmware Configuration Tool v2 on Tue Feb 26 2019 21:31:01 GMT+0000 (Greenwich Mean Time)

G91 ; relative positioning

G1 S1 X490 Y490 Z490 F1800 ; move all towers to the high end stopping at the endstops(S1 checks for endstops) (first pass)

;below 3 comment/uncomment
G1 X-5 Y-5 Z-5 F1800 S2 ; go down a few mm GARYuncomment (S2 - Ignore endstops while moving. Also ignore if axis has not been homed.)
G1 S1 X10 Y10 Z10 F360 ; move all towers up once more (second pass) GARYuncomment
G1 Z-5 F6000 ; move down a few mm so that the nozzle can be centred GARYuncomment

G1 Z-10 F1800 ;need to move down for x0 y0 to complete

G90 ; absolute positioning

G1 X0 Y0 F1800 ;force to centre
;G92 Z456.747

[jay_s_uk]

One thing I have noticed is your endstop adjustments in M666 are a lot larger than mine

M666 X0.081 Y0.238 Z-0.319 A0.00 B0.00

What 'S' value are you using at the end of your bed file?

[Gary]

@jay_s_uk
I'm sure it's your bed file with S6

[jay_s_uk]

Try overriding the M665 and M666 values and then reprobe.
I.e. resend whats in config and then probe

[Gary]

@jay_s_uk
Yeah I did that before. I deleted config override and re-probed, but I've noticed that re-probing overwrites the M665 and M666 values in the override file. Worth another try though. When you said your endstop adjustments were smaller than mine by how much?

[jay_s_uk]

@Gary

The code I included is my endstop M666.

As you can see, my X is 0.081. Yours is -6.790