I am working on a continuous fiber feeder that injects into a paste extruder, but I can't seem to get the feedrate right when extruding both the paste and fiber at the same time. I have tried both G1 Exxx:xxx F commands, as well as setting a mix ratio then using G1 E F commands. In both instances, I set the feedrate to be the feedrate for the actual material (not the fiber) as it is the larger of the two extrusion distances. My understanding was that the larger of the two distances/E's would be set to the specified feedrate, and the lesser would be 'downclocked' to start and finish at the same time (i.e., extruded at a lower feedrate); but this does not seem to be the case.
When using the same feedrate as I do with normal (non-fiber injected) extrusions, the fiber/paste extrusions do not finish on time. To test the theory that the feedrate needs to be increased when extruding two materials at once, i set the feedrate to 1.7698x its nominal value (due to my mix ratio of 1:0.7698); when I did this, it finished too early.
My question is, what should the feedrate be when extruding two materials? I cannot find much, if any, documentation on this. Or am I going about this completely wrong?
Config with unneccessary parts removed below, firmware is 3.4.4. Note I only using the duet for extrusion and secondary systems, we do not control motion with it.
Thanks!!
; General preferences
M575 P1 S1 B57600 ; enable support for PanelDue
G90 ; send absolute coordinates...
M83 ; ...but relative extruder moves
M550 P"MRAM" ; set printer name
G4 S2 ; wait for expansion boards to start
; Drives
M569 P0.3 S1 ; physical drive 0.3 goes forwards
M569 P0.1 S1 D0 ; physical drive 0.1 goes forwards
M569 P0.2 S1 ; physical drive 0.2 goes forwards
M569 P0.0 S1 ; physical drive 0.0 goes forwards
M569 P0.4 S1 ; physical drive 0.4 goes forwards
M569 P0.5 S1 D0 ; physical drive 0.5 goes forwards
M569 P21.0 S1 ; Set vipro toolboard wire feeder stepper drive direction
M569 P20.0 S1 D3 ; Set wire cutter toolboard stepper drive direction, turn on stealthchop
M584 X20.0 Y0.3 Z0.2 E0.0:0.5:0.1:21.0 ; set drive mapping
M350 X16 Y16 Z16 E16:1:1:16 I0 ; configure microstepping with interpolation
;M92 X80.00 Y80.00 Z400.00 E274.00:1594.77:1594.77
M92 X400 Y80.00 Z400.00 E274.00:180:180:383.5 ; set steps per mm
M566 X120.00 Y900.00 Z60.00 E120.00:1500000.00:1500000.00:6000.00 ; set maximum instantaneous speed changes (mm/min)
M203 X5000 Y6000.00 Z180.00 E6000.00:8000:8000:6000 ; set maximum speeds (mm/min)
M201 X100.00 Y500.00 Z20.00 E100.00:10000.00:10000.00:1000.00 ; set accelerations (mm/s^2)
M906 X1600 Y300 Z300 E2700:1200:1200:1600 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout
; Axis Limits
M208 X-50 Y0 Z0 S1 ; set axis minima
M208 X50 Y750 Z750 S0 ; set axis maxima
; Vipro Control
M302 P1 ;allow cold extrude
M569 P0.1 T21:21:0:0
M569 P0.5 T21:21:0:0
M950 P0 C"out3" ;Vipro Drivers on/off
M950 P2 C"out8" ;Vipro Syringe Air Supply
M950 P6 C"io8.out" ;UV Lights
; Tools
M563 P0 S"Typhoon" D0 H1:0 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
M563 P1 S"Vipro 415" D1 F0 ; define tool 1
G10 P1 X0 Y0 Z0 ; set tool 1 axis offsets
G10 P1 R0 S0 ; set initial tool 1 active and standby temperatures to 0C
M563 P2 S"Vipro 414" D2 F0 ; define tool 2
G10 P2 X0 Y0 Z0 ; set tool 2 axis offsets
G10 P2 R0 S0 ; set initial tool 2 active and standby temperatures to 0C
M563 P3 S"Both Vipros" D1:2 F0
G10 P3 X0 Y0 Z0 ; set tool 2 axis offsets
G10 P3 R0 S0 ; set initial tool 2 active and standby temperatures to 0C
M563 P4 S"Wire Feeder" D3 F0
G10 P4 X0 Y0 Z0 ; set tool 3 axis offsets
G10 P4 R0 S0 ; set initial tool 3 active and standby temperatures to 0C
M563 P5 S"Vipro 415 and Wire Feeder" D1:3 F0
G10 P5 X0 Y0 Z0 ; set tool 4 axis offsets
G10 P5 R0 S0 ; set initial tool 4 active and standby temperatures to 0C
M567 P5 E1.0:0.7698 ;set mix ratio
M563 P6 S"Both Vipros and Wire Feeder" D1:2:3 F0
G10 P6 X0 Y0 Z0 ; set tool 4 axis offsets
G10 P6 R0 S0 ; set initial tool 4 active and standby temperatures to 0C