Two different motors used by E0

DuetUser

Hi,

I'm going to add a secondary filament drive motor for at filament spool to offload main extruder. Extruder motor is 25mm 1.0A 200 steps one and the helper motor is 42mm 1.6A 400 steps one to provide the same gear ratio.

Is there a possibility to connect one motor to E0 driver, the second motor to E1 driver and drive both at the same time while extruding?

It's easy to do for Z axis with M584 X0 Y1 Z2:3 E4 or something, but M584 X0 Y1 Z2 E3:4 assigns different drivers to E0 and E1.

I'm currently on RRF 1.21 and Duet 2 Ethernet.

Connecting two motors to one driver ine series leaves the small one underpowered (it has 2x larger resistance)

Norder

@duetuser
Two extruders are to be used here for conveying filament.
Maybe it will help you ?

DuetUser

@norder Great! Thanks!

dc42

@duetuser you can configure them as separate extruders but then adjust your M563 tool definition to use both of then as if you have a mixing extruder, and then set the M567 mix ratio to 1:1.

DuetUser

@dc42 Thanks a lot! works like a charm!

DuetUser

When 2 motors are connected this way is it possible to drive only one of them (to load filament)
One way would be to create a dummy tool :

M563 P1 D1

and driving it :

T1
G1 E1500 F1000

but it is too much of a hack.

I know there is M302 P0 to allow cold extrusion, but is there a
way to force a certain piece of silicon on the board to feed pulses to connected motor?

deckingman

@duetuser said in Two different motors used by E0:

When 2 motors are connected this way is it possible to drive only one of them (to load filament)
One way would be to create a dummy tool :

M563 P1 D1

and driving it :

T1
G1 E1500 F1000

but it is too much of a hack.

I know there is M302 P0 to allow cold extrusion, but is there a
way to force a certain piece of silicon on the board to feed pulses to connected motor?

Assuming you have a tool defined thus....
M563 D0:1
.......to use two extruders. Then you can use the form G1 E1500:0 F1000 which will extrude 1500 mm of filament using extruder drive 0. Or you can use G1 E0:1500 which will use extruder drive 1. When the colon separator is used thus, the mixing ratio to ignored.

DuetUser

@deckingman
Ofcourse! Thanks a lot it's so elegant!