Hot end fan switches off at the start of the print.

[GrahamExp]

@dc42 so like this?
; Fans
M950 F0 C"out8" Q0 ; create fan 0 on pin out7 and set its frequency - Part Cooling Fan
M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"out7" Q500 ; create fan 1 on pin out8 and set its frequency - Hotend Cooling Fan
M106 P1 S1 T45 H1 ; set fan 1 value. Thermostatic control is turned on

[GrahamExp]

@grahamexp So what happens now is that the hot end fan (fan 1) starts up at 45 degrees but as soon as the printing begins it switches off again. Part cooling fan is now fan 0.

[SIam]

@grahamexp please post the first 50- 100 lines from your generated g-code

[GrahamExp]

@siam ;FLAVOR:RepRap
;TIME:1471
;Filament used: 0.844173m
;Layer height: 0.25
;MINX:127.88
;MINY:109.761
;MINZ:0.3
;MAXX:173.172
;MAXY:190.237
;MAXZ:69.428
;ARCWELDERPROCESSED
;LINEARADVANCEPROCESSED
; Postprocessed by ArcWelder
; Copyright(C) 2020 - Brad Hochgesang
; resolution=0.05mm
; path_tolerance=1%
; max_radius=1000000.00mm
; firmware_compensation=True
; mm_per_arc_segment=1.00mm
; min_arc_segments=12
; default_xyz_precision=3
; default_e_precision=5

;Generated with Cura_SteamEngine 4.8.0
T0
M190 S70
M104 S255
M109 S255
M82 ;absolute extrusion mode
G28 ;Home
G1 Z15.0 F6000 ;Move the platform down 15mm
;Prime the extruder
G92 E0
G1 F200 E3
G92 E0
M83 ;relative extrusion mode
G1 F1500 E-2.5
;LAYER_COUNT:278
M572 S0.550000 D0 ;added by LinearAdvanceSettingPlugin
;LAYER:0
M107
G0 F1800 X129.314 Y111.721 Z0.3
;TYPE:SKIRT
G1 F1500 E2.57838
G3 X131.478 Y110.170 I4.273 J3.677 E0.05677 F1800
G3 X134.459 Y109.809 I2.190 J5.596 E0.06412
G3 X148.452 Y112.224 I-9.081 J94.362 E0.30040
G3 X167.834 Y128.297 I-8.557 J30.041 E0.54778
G3 X173.150 Y151.443 I-42.633 J21.975 E0.50717
G3 X166.571 Y173.960 I-48.325 J-1.900 E0.50082
G3 X145.391 Y188.503 I-26.690 J-16.176 E0.55959
G3 X134.082 Y190.219 I-20.282 J-95.543 E0.24187
G3 X131.450 Y189.818 I-0.490 J-5.620 E0.05677
G3 X129.295 Y188.255 I2.132 J-5.207 E0.05677
G3 X128.096 Y185.878 I4.291 J-3.655 E0.05677
G3 X127.968 Y182.725 I8.568 J-1.927 E0.06706
G3 X128.417 Y181.251 I9.908 J2.213 E0.03259
G2 X128.161 Y118.021 I-89.047 J-31.255 E1.36259
G3 X127.893 Y115.782 I5.351 J-1.776 E0.04794
G3 X128.567 Y112.834 I7.467 J0.156 E0.06441
G3 X129.314 Y111.721 I4.978 J2.534 E0.02838
G0 X129.721 Y111.906
G3 X131.849 Y110.487 I3.872 J3.502 E0.05457
G3 X134.415 Y110.235 I1.804 J5.177 E0.05495
G3 X148.343 Y112.638 I-8.992 J93.687 E0.29899
G3 X167.386 Y128.359 I-8.429 J29.604 E0.53701
G3 X172.726 Y151.316 I-42.320 J21.944 E0.50335
G3 X165.883 Y174.252 I-46.997 J-1.533 E0.51142
G3 X145.303 Y188.084 I-26.019 J-16.486 E0.53936
G3 X134.045 Y189.792 I-20.170 J-94.993 E0.24080
G3 X131.520 Y189.383 I-0.456 J-5.186 E0.05458
G3 X129.494 Y187.823 I2.074 J-4.789 E0.05456
G3 X128.603 Y186.115 I4.064 J-3.206 E0.04092
G3 X128.393 Y182.780 I7.886 J-2.171 E0.07113
G3 X129.680 Y178.828 I75.446 J22.384 E0.08787
G2 X128.567 Y117.886 I-90.315 J-28.832 E1.31137
G3 X128.374 Y115.147 I5.612 J-1.772 E0.05851
G3 X128.983 Y112.962 I5.422 J0.334 E0.04826
G3 X129.721 Y111.906 I4.580 J2.415 E0.02728
G1 F1500 E-2.5
;MESH:Canopy_1.stl
G0 F1800 X137.542 Y183.534
;TYPE:WALL-OUTER
G1 F1500 E2.57838
G3 X139.669 Y180.068 I310.315 J188.047 E0.08596 F1800
G3 X143.539 Y176.885 I8.004 J5.787 E0.10704
G3 X145.915 Y176.082 I8.132 J20.146 E0.05305
G2 X153.745 Y171.178 I-5.581 J-17.613 E0.19731
G2 X158.010 Y164.600 I-15.846 J-14.946 E0.16657
G2 X161.219 Y148.753 I-32.558 J-14.841 E0.34471
G2 X156.708 Y132.780 I-36.464 J1.674 E0.35382
G2 X149.723 Y125.622 I-17.042 J9.643 E0.21368
G2 X144.322 Y123.436 I-11.154 J19.793 E0.12353
G3 X140.198 Y120.599 I3.357 J-9.296 E0.10693
G3 X139.204 Y119.229 I7.436 J-6.440 E0.03580
G2 X137.548 Y116.476 I-260.902 J155.064 E0.06790
G2 X133.733 Y116.029 I-12.269 J88.209 E0.08117
G1 X133.774 Y115.625 E0.00858
G3 X147.119 Y117.926 I-8.473 J88.991 E0.28216
G3 X162.737 Y131.183 I-7.194 J24.303 E0.44567
G3 X167.287 Y151.609 I-37.413 J19.054 E0.44692
G3 X161.434 Y171.144 I-42.187 J-1.996 E0.43529
G3 X144.646 Y182.677 I-21.406 J-13.174 E0.44308
G3 X133.773 Y184.374 I-20.367 J-94.816 E0.23267
G1 X133.733 Y183.971 E0.00856
G2 X137.542 Y183.534 I-19.285 J-184.910 E0.07656
G0 X137.562 Y183.501
G0 X137.645 Y183.363
G0 X138.092 Y183.43
;TYPE:SKIN
G3 X140.001 Y180.322 I37.766 J21.057 E0.07709
G3 X143.716 Y177.264 I7.678 J5.542 E0.10278
G3 X146.040 Y176.481 I7.921 J19.670 E0.05188
G2 X154.046 Y171.467 I-5.708 J-18.012 E0.20174
G2 X158.392 Y164.770 I-16.139 J-15.232 E0.16964
G2 X161.637 Y148.737 I-32.932 J-15.010 E0.34873
G2 X157.071 Y132.573 I-36.871 J1.688 E0.35807
G2 X149.936 Y125.262 I-17.402 J9.846 E0.21826
G2 X144.463 Y123.042 I-11.377 J20.192 E0.12521
G3 X140.511 Y120.321 I3.220 J-8.908 E0.10250
G3 X139.552 Y118.998 I7.107 J-6.161 E0.03456
G1 X138.092 Y116.57 E0.05987
G3 X147.626 Y118.515 I-8.784 J67.395 E0.20581
G3 X162.362 Y131.368 I-7.771 J23.783 E0.42455
G3 X166.869 Y151.588 I-37.010 J18.862 E0.44243
G3 X161.082 Y170.918 I-41.713 J-1.957 E0.43070
G3 X144.511 Y182.279 I-21.068 J-12.964 E0.43715
G3 X138.092 Y183.430 I-19.716 J-91.482 E0.13784
G0 X138.664 Y182.85
G1 X138.923 Y183.108 E0.00773
G0 X139.447 Y183.028
G1 X138.891 Y182.471 E0.01663
G0 X139.119 Y182.094
G1 X139.968 Y182.943 E0.02537
G0 X140.486 Y182.856
G1 X139.345 Y181.715 E0.0341
G0 X139.572 Y181.337
G1 X141.003 Y182.768 E0.04277
G0 X141.515 Y182.674
G1 X139.806 Y180.965 E0.05108
G0 X140.047 Y180.601
G1 X142.027 Y182.581 E0.05918
G0 X142.535 Y182.483
G1 X140.303 Y180.252 E0.06669
G0 X140.57 Y179.914
G1 X143.041 Y182.384 E0.07384
G0 X143.545 Y182.283
G1 X140.855 Y179.593 E0.0804
G0 X141.149 Y179.281
G1 X144.046 Y182.178 E0.08658
G0 X144.543 Y182.07
G1 X141.462 Y178.989 E0.09208
G0 X141.782 Y178.704
G1 X145.036 Y181.959 E0.09727
G0 X145.53 Y181.847
G1 X142.127 Y178.444 E0.10171
G0 X142.476 Y178.188
G1 X146.019 Y181.731 E0.10589
G0 X146.501 Y181.608
G1 X142.848 Y177.954 E0.10919
G0 X143.228 Y177.729
G1 X146.977 Y181.478 E0.11205
G0 X147.44 Y181.336
G1 X143.628 Y177.524 E0.11393
G0 X144.046 Y177.336
G1 X147.9 Y181.191 E0.1152
G0 X148.349 Y181.034
G1 X144.476 Y177.161 E0.11575
G0 X144.932 Y177.012
G1 X148.791 Y180.871 E0.11534
G0 X149.228 Y180.703
G1 X145.395 Y176.87 E0.11456
G0 X145.863 Y176.732
G1 X149.656 Y180.525 E0.11336
G0 X150.079 Y180.343
G1 X146.323 Y176.587 E0.11226
G0 X146.774 Y176.433
G1 X150.495 Y180.154 E0.11121
G0 X150.902 Y179.956
G1 X147.216 Y176.27 E0.11017
G0 X147.648 Y176.097
G1 X151.303 Y179.751 E0.10922
G0 X151.697 Y179.54
G1 X148.072 Y175.915 E0.10834
G0 X148.486 Y175.723
G1 X152.088 Y179.326 E0.10767
G0 X152.472 Y179.104
G1 X148.893 Y175.525 E0.10697
G0 X149.293 Y175.32
G1 X152.848 Y178.876 E0.10627
G0 X153.22 Y178.642
G1 X149.685 Y175.107 E0.10565
G0 X150.067 Y174.884
G1 X153.585 Y178.402 E0.10514
G0 X153.945 Y178.156
G1 X150.443 Y174.654 E0.10467
G0 X150.808 Y174.414
G1 X154.301 Y177.907 E0.1044
G0 X154.649 Y177.65
G1 X151.172 Y174.173 E0.10392
G0 X151.523 Y173.919
G1 X154.993 Y177.389 E0.10371
G0 X155.331 Y177.121
G1 X151.868 Y173.659 E0.10349
G0 X152.213 Y173.398
G1 X155.663 Y176.848 E0.10311
G0 X155.99 Y176.57
G1 X152.544 Y173.123 E0.10301
G0 X152.869 Y172.843
G1 X156.313 Y176.287 E0.10293
G0 X156.629 Y175.998
G1 X153.194 Y172.563 E0.10266
G0 X153.504 Y172.268
G1 X156.94 Y175.704 E0.10269
G0 X157.247 Y175.406
G1 X153.809 Y171.968 E0.10275
G0 X154.115 Y171.668
G1 X157.549 Y175.102 E0.10263
G0 X157.845 Y174.793
G1 X154.406 Y171.354 E0.10278
G0 X154.694 Y171.037
G1 X158.136 Y174.479 E0.10287
G0 X158.422 Y174.159
G1 X154.982 Y170.719 E0.10281
G0 X155.253 Y170.385
G1 X158.703 Y173.835 E0.10311
G0 X158.978 Y173.505
G1 X155.521 Y170.048 E0.10332
G0 X155.789 Y169.71
G1 X159.249 Y173.171 E0.10343
G0 X159.516 Y172.832
G1 X156.042 Y169.358 E0.10383
G0 X156.293 Y169.004
G1 X159.777 Y172.488 E0.10413
G0 X160.03 Y172.135
G1 X156.543 Y168.649 E0.1042
G0 X156.774 Y168.275
G1 X160.281 Y171.781 E0.1048
G0 X160.526 Y171.421
G1 X157.004 Y167.899 E0.10526
G0 X157.235 Y167.524
G1 X160.764 Y171.054 E0.10549
G0 X160.999 Y170.683
G1 X157.445 Y167.13 E0.10621
G0 X157.655 Y166.735
G1 X161.23 Y170.309 E0.10683
G0 X161.452 Y169.926
G1 X157.863 Y166.337 E0.10727
G0 X158.058 Y165.926
G1 X161.67 Y169.538 E0.10795
G0 X161.883 Y169.147
G1 X158.251 Y165.515 E0.10855
G0 X158.446 Y165.104
G1 X162.087 Y168.745 E0.10882
G0 X162.287 Y168.34
G1 X158.634 Y164.687 E0.10918
G0 X158.814 Y164.261
G1 X162.481 Y167.929 E0.10961
G0 X162.676 Y167.519
G1 X158.993 Y163.835 E0.11009
G0 X159.173 Y163.41

[SIam]

@grahamexp said in Hot end fan switches off at the start of the print.:

M107

look at your start g code you have a m170 some wehre and this switch off your fan

[GrahamExp]

@siam M107 or M170? I see M107 not M170

[SIam]

@grahamexp
I mean this:

;LAYER:0
M107
G0 F1800 X129.314 Y111.721 Z0.3

Somewhere in your slicer will add this and this switch your fan off

M107: Fan Off

Deprecated in RepRapFirmware. Use M106 S0 instead.

Note that M107 will turn off the print cooling fan(s) associated with the current tool (see the F parameter in the M563 command).

[GrahamExp]

@siam I see it, so how do I stop this from happening?

[GrahamExp]

@grahamexp OK but that is the current tool fan and it set to be using tool 0 the hot end fan is set to be fan 1 so it should then not be affected, right?

[SIam]

@grahamexp mmmhh I understand this so that this is the hot end cooler

[dc42]

@grahamexp that looks better. Now please post your complete config.g file.

[GrahamExp]

@siam yes corect I want it always on .. or at least on as soon as it reached 45 deg. It should not be affected by the g code at all in preference. like on the older duet 2 board you had those always on fan pins.

[GrahamExp]

@grahamexp ; Configuration file for Duet 3 (firmware version 3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.2.2 on Mon Feb 01 2021 21:18:26 GMT+0200 (South Africa Standard Time)

; General preferences
G90 ; Send absolute coordinates
M83 ; Relative extruder moves
M550 P"Viking 300" ; Set printer name to Viking 300
M669 K1 ; Select CoreXY mode
G21 ; Set to milimeters
M111 S0 ; Debugging off

; Network
M552 P192.168.0.176 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 P0.0 S1 ; physical drive 0.0 goes forwards
M569 P0.1 S1 ; physical drive 0.1 goes forwards
M569 P0.2 S1 ; physical drive 0.2 goes backwards
M569 P0.3 S1 ; physical drive 0.3 goes forwards
M584 X0.1 Y0.0 Z0.2 E0.3 ; set drive mapping
M350 X16 Y16 Z16 E16 I1 ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z3204 E1004.00 ; set steps per mm
M566 X900.00 Y900.00 Z60.00 E500 ; set maximum instantaneous speed changes (mm/min)
M203 X18000.00 Y18000.00 Z360.00 E3000.00 ; set maximum speeds (mm/min)
M201 X3000.00 Y3000.00 Z360.00 E3000.00 ; set accelerations (mm/s^2)
M906 X800 Y800 Z1000 E1200 ; set motor currents (mA) and motor idle factor in per cent
;M84 S30 ; Set idle timeout

; Axis Limits
M208 X-5 Y0 Z0 S1 ; set axis minima
M208 X300 Y300 Z360 S0 ; set axis maxima

; Endstops
M574 X1 S3 ; configure sensorless endstop for high end on X
M574 Y2 S3 ; configure sensorless endstop for high end on Y
M574 Z1 S2 ; configure Z-probe endstop for low end on Z

;Stall Detection
M915 X Y S3 R0 ; Stall detection on the X and Y axis With sensitivity set by S and Action set by R ("Take3 No Action")

;Pressure/Linear Advance
;M572 D0 S0.75 ; Pressure/Linear advance enabled with D selecting tool and S selecting value.

; Z-Probe
M950 S0 C"io7.out" ; create servo pin 0 for BLTouch
M558 P9 C"^io7.in" H5 F360 T6000 A1 B0.2 ; set Z probe type to bltouch and the dive height + speeds
G31 P500 X-71 Y-42 Z3.0632 ; set Z probe trigger value, offset and trigger height
M557 X15:215 Y15:195 S40 ; define mesh grid

; Heaters
M308 S0 P"temp0" Y"thermistor" T100000 B4138 ; configure sensor 0 as thermistor on pin temp0
M950 H0 C"out0" T0 ; create bed heater output on out0 and map it to sensor 0
M307 H0 B1 S1.00 ; enable bang-bang mode for the bed heater and set PWM limit
M140 H0 ; map heated bed to heater 0
M143 H0 S120 ; set temperature limit for heater 0 to 120C
M308 S1 P"temp1" Y"thermistor" T100000 B4138 ; configure sensor 1 as thermistor on pin temp1
M950 H1 C"out1" T1 ; create nozzle heater output on out1 and map it to sensor 1
M307 H1 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit
M143 H1 S275 ; set temperature limit for heater 1 to 275C

; Fans
M950 F0 C"out8" Q0 ; create fan 0 on pin out8 and set its frequency - Part Cooling Fan
M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off
M950 F1 C"out7" Q500 ; create fan 1 on pin out7 and set its frequency - Hotend Cooling Fan
M106 P1 S1 T45 H1 ; set fan 1 value. Thermostatic control is turned on

; Tools
M563 P0 D0 H1 F0:1 ; 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

; Custom settings are not defined

; Miscellaneous
M575 P1 S1 B57600 ; enable support for PanelDue - io_0
M501 ; load saved parameters from non-volatile memory
M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; set voltage thresholds and actions to run on power loss

[Phaedrux]

@grahamexp said in Hot end fan switches off at the start of the print.:

; Tools
M563 P0 D0 H1 F0:1 ; define tool 0

You've got both fan0 and fan1 assigned to tool0 as the part cooling fan.

Change F0:1 to be F0

[GrahamExp]

@phaedrux problem solved. thank you for your help