y slope with 3.5.0-rc1, not seen with 3.4.6

Adrian52

Have been using 3.5.0-rc1 for a while with no major problems, but printing a simple model today showed up a strange slope in the y direction:
alt text
The same gcode file using 3.4.6(left) and 3.5.0-rc1(right)
The 'y' side slopes to the bottom of the 'U' cutout, and is then vertical.
When printing the same .stl rotated 90deg, a similar effect is seen, although the 'y' face becomes vertical from the square cutout. The X face is vertical in all the prints.
The right print is after reinstalling 3.5.0-rc1 immediately after printing the left print with 3.4.6.
The .stl file used was generated in openScad, simply subtracting cubes and cylinder from the original 20x20 cube (it is a jig for aligning bits for glueing).

gloomyandy

@Adrian52 It's not easy to see what is happening with the far y side, does that slope/shift as well or is just the y side closer to the camera that has shifted? A photo looking straight on from the x side might help get a better idea of what is happening.

o_lampe

@Adrian52 Is your max-speed and retraction setting the same with both FW?
Maybe you are slicing with a high travel speed, but 3.4.6 limits it while 3.5.1 doesn't...

Adrian52

@gloomyandy the slope is parallel on both the +y and -y faces, about 10deg to the vertical
Should have said I am running a kossel xl style delta, with a 1.01 duet 2wifi

Adrian52

@o_lampe I am using fw retraction, and the same gcode file was used for both prints

nikscha

@Adrian52 what are the print-times for both firmwares? If 3.5.0-rc1 is lower then @o_lampe might be onto something. Be sure to check the print times in the webinterface, not in the slicer.

Adrian52

@nikscha didn't note the print time for the 3.4.6 print - will have to do that again.
Have tried 3.5rc1 with input shaping set to "none", but the slope is exactly the same.

o_lampe

@Adrian52 said in y slope with 3.5.0-rc1, not seen with 3.4.6:

the same gcode file was used for both prints

That's what I meant. The slicer might have put insane high travel speeds in the gcode. It's up to RRF-config to cut that off.
(or set it right in the slicer printer profile and slice again)

Adrian52

@o_lampe I am in the process of finding out at what version the change occurred, and so far have :
3.5beta4 - slope
3.5beta1 - no slope
the print time was 20min exactly for both prints

Adrian52

With regard to versions showing this effect, the change seems to occur between 3.5beta2 (no slope) and 3.5beta3 (slope).
I have tried to get the minimal conditions to see the transition from sloped to vertical, as I had seen a change when rotating my original model; the y sides became vertical at the bottom of the y cutout. I have used a simpler 20x20x20 cube with a 2x2x2 cut out 10mm from the base.
If I put the small cutout on the y+ face of the cube, the y face is vertical from then on:
alt text
The cube is positioned with the -x face up, and the +y face to the left.
If I put the cutout on the y- face (or the x faces) the slope continues to the top.
The slicer has put the seam at the +x,+y corner, and the print path is anticlockwise, so y+ is the first perimeter of each layer to be printed.

Adrian52

On further testing, the seam position doesn't seem to affect things - with the seam at the x0y+ corner, the cutout on the y+ face still makes the print vertical from the level of the cutout (as above).
I also compared 0.15 layers with 0.25 layers, and the slope looks exactly the same. Tried measuring the slope more precisely - seems to be about 1.4mm over 20mm, about 4deg.

nikscha

@Adrian52 can you post your config?
I also had a look at the changelog between beta2 and beta3, but I don't see any change that might cause your problem. Maybe have a look yourself: https://github.com/Duet3D/RepRapFirmware/wiki/Changelog-RRF-3.x-Beta#reprapfirmware-350beta3

Adrian52

@nikscha
This rabbit hole gets curioser and curioser.

First, this is my config.g: as you see, I am using 2 orbiter extruders in tandem

; Think3DPrint3D configuration file for Mini Kossel for testing Duet WiFi

; Communication and general
M111 S0                             	; Debug off
M550 PKosselXL							; Machine name and Netbios name (can be anything you like)
M551 Preprap                        	; Machine password (used for FTP)
;*** If you have more than one Duet on your network, they must all have different MAC addresses, so change the last digits
;M540 P0xBE:0xEF:0xDE:0xAD:0xFE:0xED 	; MAC Address
;*** Wifi Networking
M552 S1									; Enable WiFi. Disabled for setup and testing. Enable once set up on your network.
M555 P0                           		; Set output to look like Reprap
M575 P1 B57600 S1						; Comms parameters for PanelDue
G21                                 	; Work in millimetres
G90                                		; Send absolute coordinates...
M83                                 	; ...but relative extruder moves

; Axis and motor configuration
M584 X0 Y1 Z2 E3:4						;explicitly assign drives
M569 P0 S0								; Drive 0 goes backwards - changed to backwards for robodigg clamps
M569 P1 S0								; Drive 1 goes backwards - "
M569 P2 S0								; Drive 2 goes backwards - "
M569 P3 S0								; Drive 3 goes backwards - changed for orbiter 1.5
M569 P4 S0								; Drive 4 goes backwards - orbiter 2.0
M84 S120								;set idle timeout to 120sec
;M574 X2 Y2 Z2 S1						; set endstop configuration (all endstops at high end, active high)
M574 X2 S1 P"xstop"
M574 Y2 S1 P"ystop"
M574 Z2 S1 P"zstop"
;*** The homed height is deliberately set too high in the following - you will adjust it during calibration
M665 L360.25 R173.990 H297.084 B120.0 X0.538 Y0.525 Z0.000
M666 X1.493 Y-1.213 Z-0.280 A-1.03 B-0.66		; put your endstop adjustments here, or let auto calibration find them
M579 X1.005 Y1.007 Z1.00		        	;correct x y z scaling
M350 X16 Y16 Z16 I1	    				; Set 16x microstepping with interpolation
M350 E16:16 I1								; Set exruder to 16x with interpolation
M92 X200 Y200 Z200						; Set axis steps/mm
M906 X1400 Y1400 Z1400 I0.6		; Set motor currents (mA) and increase idle current to 60%
M906 E850:850 I10							;current for orbiter
M201 X2800 Y2800 Z2800 E5000:5000			; Accelerations (mm/s^2)
M203 X20000 Y20000 Z20000 E7200:7200			; Maximum speeds (mm/min)
M566 X2100 Y2100 Z2100 E3000 P1			; Maximum instant speed changes mm/minute, switch on 2.03 jerk policy

; Thermistors and heaters

M308 S0 P"bedtemp" A"Bed temp" Y"thermistor" T100000 B4138      ; configure sensor 0 as thermistor on pin bedtemp
M950 H0 C"bedheat" T0                               ; create bed heater output on bedheat and map it to sensor 0
M307 H0 B0 S1.00                                    ; disable bang-bang mode for the nozzle heater and set PWM limit
M140 H0									;bed heater is heater 0 
M143 H0 S125
M308 S1 P"e0temp" Y"thermistor" T100000 B4725 C7.060000e-8 A"Extruder temp"  ; configure sensor 1 as thermister via e0temp
M308 S2 P"e1temp" Y"thermistor" T100000 B4725 C7.060000e-8 A"Cold end temp"  ; configure sensor 2 as thermister via e1temp
;M308 S1 P"spi.cs1" Y"rtdmax31865" A"Extruder temp"  ; configure sensor 1 as thermocouple via CS pin spi.cs1
;M308 S2 P"spi.cs2" Y"rtdmax31865" A"Test temp"		; configure sensor 2
M950 H1 C"e0heat" T1                                ; create nozzle heater output on e0heat and map it to sensor 1
M950 P2 C"e1heat"									; create output to switch lights
M307 H1 B0 S1.00                                    ; disable bang-bang mode for the nozzle heater and set PWM limit
M143 H1 S300                                        ; set temperature limit for heater 1 to 295C
M570 H1 S60											;cancel print 60min after extruder temp fault

; ****Fans
M950 F0 C"fan0" Q500                               ; create fan 0 on pin fan0 and set its frequency
M106 P0 S0 H-1                                      ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"fan1" Q2500                                ; create fan 1 on pin fan1 and set its frequency
M106 P1 S1 H1 T45                                   ; set fan 1 value. Thermostatic control is turned on
M950 F2 C"!Fan2+^exp.pb6" Q25000
M106 P2 S0 H-1 C"Extra cool"
; Tools
M563 P0 D0:1 H1 F0                                   ; 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

; Tool definitions
;M563 P0 D0 H1 F0:2                     			; Define tool 0 with fan 0, fan 2 linked
;M563 P0 D0 H1 F0 									; tool 0 with fan 0 only
G10 P0 S0 R0                        				; Set tool 0 operating and standby temperatures
M567 P0 E1.00:1.00									; set mix ratio
M309 p0 S0.006										; set heater feed forward for tool 0
;*** If you have a single-nozzle build, comment the next 2 lines
;M563 P1 D1 H2                      					; Define tool 1
;G10 P1 S0 R0                       				; Set tool 1 operating and standby temperatures
;M92 E458                        					; Set extruder steps per mm
M92 E667:667                        					; Set extruder steps per mm orbiter
M572 D0:1 S0.04											;pressure advance extruder 0 and 1
;M572 D1 S0.02										; pressure advance extruder 1
M207 S2.1 R0.0 F7200 Z0.05             		; firmware retraction setting

; Z probe and compensation definition
M558 P8 C"zprobe.in+zprobe.mod" R0.4 F1000 H5 A2 S-1		;Z probe smart effector
M672 S105:20:235									;set z probe sensitivity
;G31 P100 X0 Y0 Z-0.10								;probe offset for old smart effector
G31 P100 X0 Y0 Z-0.02								;probe offset for new smart effector 0.27 for petg 0.18 for pla try 0.1 for direct drive

   												;laser filament monitor settings
M591 D0 P5 C"connlcd.encb" R01:300 E10 L0.398 S1 A1		;version for reprap3

;M955 P0 C"spi.cs3+spi.cs4" I64 S5000 R10							;accelerometer configuration

;*** If you are using axis compensation, put the figures in the following command
M556 S100 X0.05 Y0 Z0                  				; Axis compensation here
M593 P"ei3" F30 L400 S0.0							; Damp ringing at 30Hz
M376 H10											;taper mesh over 10mm
M501												;use override-config.g parameters
M208 S1 Z-0.2										; set minimum Z
M912 P0 S-2											;calibration mcu temperature reading
G28													;Home axes
M42 P2 S1											;lights on
;G29 S1												;load height map and activate mesh compensation
;M290 S-0.1											;current baby steps 
;
T0													; select first hot end

I have made a couple more observations:

When printing 2 cubes together, the slope on each seems to be half that of a single cube. Similarly, printing a cube rotated 45deg, so that a corner is pointing in the y direction, the two +y direction faces are sloping with half the slope, but the -y direction faces are vertical.

As I had previously seen that a cutout on the y+ face of a cube made the print vertical from that point, I wondered if a tab on the y+ face might have the same effect. The answer is no - a 2x2x2 cube attached at the bottom middle of the y+ face results in half the slope seen with no cube. A 2x2x2 cutout in the same position gives a vertical cube.

Adrian52

A further note on versions - I just tried 3.5beta2+ (2023-02-10), and this gives no slope - a perfectly vertical cube.

dc42

@Adrian52 thanks for reporting this and for your investigations. We've created this issue https://github.com/Duet3D/RepRapFirmware/issues/924 and I will investigate it.

T3P3 created this issue in Duet3D/RepRapFirmware

closed Potential issue with delta printers #924

Adrian52

@dc42 Thank you. I just tried the 3.5rc1+ release from dropbox, and that still has the y slope.
Incidentally, the filament monitor output was still a little bit truncated:

Duet3D laser filament monitor v2 on pin (connlcd.encb,connlcd.3), enabled when SD printing, allow 1% to 300%, check all extruding moves every 10.0mm, calibration factor 0.398, quality 224, brightness 30, shutter 123, measured min 99% avg 101% max 122% over

Fred-Y

@dc42 - Adrian mentioned using a delta, 3.4.0b3 had an issue with deltas that seems similar.
https://forum.duet3d.com/topic/25166/3-4-0-b3-leaning-prints?_=1698282891138

Adrian52

@Fred-Y I was getting a bit of deja vu, but had not checked back - thanks for the link.

Adrian52

The latest rc1+ (from 31/10/2023) seems to have solved the issue. Thank you.

dc42

@Adrian52 thanks for confirming. I'll mark this thread as solved, but feel free to change it to unsolved if the issue returns.