Homing and bed probing faster but no change in printing   Had a thought re. extruder motor calibration.  The Titan uses the same extruder so I've taken the steps/mm for that and put it in the Duet.  It's a fair bit lower.  OK slightly less extrusion but otherwise no change.  The problem remains!!!

As an experiment I've let the print continue for longer having halved the extrusion rate to save filament (though this is the very cheap ABS at about £4 a Kg).  The printing speed is continually decreasing from a start which might be tolerated but now, after some 10m, it's got down to a crawl with it needing several seconds watching to be able to see any movement at all.  How weird is that!!!  Perhaps even more oddly (or maybe not) is that the extrusion rate seems to have been the same throughout the print.  It's only the XY speed that seems to have decreased or indeed to be far less than it should be.  Can't say about the Z as I haven't got past the first layer.

I would very much appreciate any help or suggestions as to what might be wrong.  I expect to get a solution to this as has happened with seemingly insoluble problems in the past.  I can't believe this is the fault of the Duet with so many others using it quite satisfactorily. 

At least today hasn't been a total loss - I've sold my last 460EX astro camera and took it to the Post Office to send to the buyer - another £1,300 for the funds   Trying to be positive

Very weird. Can you post your config.g as it stands now. The gcode file of the printed object would be useful too. I'll have a look and see if I can spot anything.

I have a gcode simulator on my tablet I can run it through to see if that is where the problem is.

config.g

; Configuration file for Duet WiFi (firmware version 1.20 or newer)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool on Mon Jan 15 2018 15:49:12 GMT+0000 (GMT)

; General preferences
M111 S0                           ; Debugging off
G21                               ; Work in millimetres
G90                               ; Send absolute coordinates...
M83                               ; ...but relative extruder moves
M555 P2                           ; Set firmware compatibility to look like Marlin
; Automatic saving after power loss is not enabled
M667 S1                           ; switch to CoreXY mode *** Gina added
M208 X0 Y0 Z0 S1                  ; Set axis minima
M208 X190 Y190 Z240 S0            ; Set axis maxima

; Endstops
M574 X1 Y1 S0                     ; Set active low endstops       **********  Gina added
M574 Z1 S2                        ; Set endstops controlled by probe
M558 P4 H7 F600 T6000 I1          ; Set Z probe type to unmodulated and the dive height + speeds  *** I1 added  speed 600mm/min
G31 P500 X24 Y0 Z1.3              ; Set Z probe trigger value, offset and trigger height
M557 X25:165 Y15:175 S70          ; Define mesh grid

; Drives
M667 S1                           ; switch to CoreXY mode *** Gina added
M569 P0 S0                        ; Drive 0 goes forwards
M569 P1 S0                        ; Drive 1 goes backwards
M569 P2 S1                        ; Drive 2 goes forwards
M569 P3 S0                        ; Drive 3 goes backwards
M350 X16 Y16 Z16 E16 I1           ; Configure microstepping with interpolation
M92 X62.45 Y62.45 Z401.02 E209.25 ; Set steps per mm        **********************    418.50 was 783.53
M566 X1200 Y1200 Z12 E120         ; Set maximum instantaneous speed changes (mm/min)  ***************
M203 X6000 Y6000 Z900 E1200       ; Set maximum speeds (mm/min)
M201 X500 Y500 Z250 E250          ; Set accelerations (mm/s^2)         ******************
M906 X1000 Y1000 Z1000 E1400 I30  ; Set motor currents (mA) and motor idle factor in per cent
M84 S30                           ; Set idle timeout

; Heaters
M305 P0 T100000 B4138 C0 R4700    ; Set thermistor + ADC parameters for heater 0
M143 H0 S150                      ; Set temperature limit for heater 0 to 150C
M305 P1 T100000 B4138 C0 R4700    ; Set thermistor + ADC parameters for heater 1
M143 H1 S300                      ; Set temperature limit for heater 1 to 300C

; Tools
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

; Network
M550 P"GinaRep Mini"              ; Set machine name
M552 S1                           ; Enable network
;*** Access point is configured manually via M587
M586 P0 S1                        ; Enable HTTP
M586 P1 S0                        ; Disable FTP
M586 P2 S0                        ; Disable Telnet

; Fans
M106 P0 S0.3 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
M106 P2 S1 I0 F500 H1 T45         ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned on

; Custom settings are not configured

gcode coming shortly...

Test Ring 100mm OD 2mm thick 10mm high 02.gcode

Trying that gcode on my Titan printer - currently heating up...

Later - printing fine on the Titan.

Config looks ok. I'll have a look at gcode.

Had a look at the gcode. First layer is at 8mm/s, rest at 12mm/s. It seems to spend a long time doing infill between the inner & outer walls - maybe thats when it slows down. Maybe try a model without a narrow wall e.g a cube.

Been analysing the situation.  The hardware must be alright because all the axes move correctly from individual commands and also homing and bed probing.  The gcode file seems alright as it is prints fine on my Titan.  That leaves the Duet.  It would seem that the gcode is somehow incompatible with the Duet - there must be differences between the Duet and RAMPS etc. plus Marlin.  Maybe a different host app and slicer.

9 minutes ago, tekkydave said:

Had a look at the gcode. First layer is at 8mm/s, rest at 12mm/s. It seems to spend a long time doing infill between the inner & outer walls - maybe thats when it slows down. Maybe try a model without a narrow wall e.g a cube.

I did try a block but that was a while back.  I'll try a small cube.

Maybe try Slic3r standalone.

Designed a 20mm cube and uploaded it to the Duet - currently heating up.

The weirdness continues!!  It started with a skirt of about the right size then started printing the main 20mm cube 110mm high   Speed is better.  X print spacing is more like 1.8mm than 0.3mm. 

36 minutes ago, tekkydave said:

Maybe try Slic3r standalone.

Yes, I will.

Downloaded the Linux version to my Linux Mint desktop, loaded the 20mm cube stl file and saved the gcode to the Duet Print folder.  Uploaded and now running the gcode.  Slic3r was blindingly fast seemed to produce the gcode instantaneously

Total rubbish!!!   Ultra slow printing except where it went from top to bottom and vice versa.  All the time extruding fast!  Hence the pile up of filament!

I think it's to do with absolute/relative extruder movement. Check you have your start gcode setup correctly in slicer. You should be able to select the right output format in slicer too.

Here's a screenshot of slic3r - can you see anything wrong?

Trying again with main printing speeds reduced.

That's a lot better but insufficient extrusion so I'll put the extrusion speed back up to what I think it should be.  Speed seems alright

20 minutes ago, Gina said:

Here's a screenshot of slic3r - can you see anything wrong?

Your settings are all set to 'default' have you adjusted them to suit the printer & filament?

Yes, I used the setup wizard.

Comparing your gcode & mine I can see you are missing a

G90 ;absolute positioning

somewhere.

Your extruder is being given absolute coordinates to go to but it is treating them as relative hence the over-extrusion. Either add one in your start g-code or set the output format to Marlin in Slicer (might be listed as 'Reprap').

Seems to be printing alright but didn't do bed probing so I'll have to add the pre-print g-code.

Maybe Slic3r has the correct output format set by default. The version of cura your Repetier Host is using is quite old now. Latest version is 2.8 I think (numbering scheme was changed - I think 15.xx became V1).

I'm letting the current print finish as it looks good   Meanwhile, I've been setting up slic3r and added my start and end g-code copied from the ABS versions for my Titan printer.

But it looks like using slic3r instead of CuraEngine has cured the problem