Independent steps per mm on E axis

Spodeopieter

I want to drive one extruder axis from the integrated E0 and E1 drivers , but with different steps per mm for the two drivers, because I have different motors driving the same axis , inline extruders on the same piece of filament.

configuration with M92 and M584 does not seem to be able to do this.

How can I make this work, do you have any ideas/suggestions ?

Can I bind one axis to another axis so they move the same amount of units ?

briskspirit

M92 E97:97 ; Set steps per mm for extruders E0 and E1

deckingman

@spodeopieter As @briskspirit said.

A real life example would be my own config which uses 5 extruders mapped to drive 5 to 9. Each extruder has been calibrated and has a slightly different value for the steps per mm. So I have:

M584 X0:3 Y1:4 Z2 U10 V11 E5:6:7:8:9

followed by

M92 X80 Y80 U80 V80 Z3200 E409:403:407:405:403

briskspirit

@deckingman Ian, may I ask you to help me check my config please? https://forum.duet3d.com/topic/7048/help-to-check-config-please

Spodeopieter

Yes , but then each would be a independent extruder axis , I need them to function as one , I have the two extruders inline , they both push the same piece of filament (I need to have very high extrusion force) .

I need Drives 3 and 4 to function together as an E-axis , but with different steps per mm , because I have two different extruders.

I can probably do it with a g code parser , but this would not be ideal.

briskspirit

@spodeopieter Make them as the one tool.

deckingman

@briskspirit said in Independent steps per mm on E axis:

@spodeopieter Make them as the one tool.

Exactly so.

Taking my real life example again, I use a mixing hot end which has 5 extruders feeding in to one nozzle. So I have for example
M563 P0 D0:1:2:3:4 H1

In your case it would simply be M563 P0 D0:1

dc42

@deckingman said in Independent steps per mm on E axis:

@briskspirit said in Independent steps per mm on E axis:

@spodeopieter Make them as the one tool.

Exactly so.

Taking my real life example again, I use a mixing hot end which has 5 extruders feeding in to one nozzle. So I have for example
M563 P0 D0:1:2:3:4 H1

In your case it would simply be M563 P0 D0:1

And then M567 E1:1 to set them to extrude equal amounts.

deckingman

@dc42 said in Independent steps per mm on E axis:

@deckingman said in Independent steps per mm on E axis:

@briskspirit said in Independent steps per mm on E axis:

@spodeopieter Make them as the one tool.

Exactly so.

Taking my real life example again, I use a mixing hot end which has 5 extruders feeding in to one nozzle. So I have for example
M563 P0 D0:1:2:3:4 H1

In your case it would simply be M563 P0 D0:1

And then M567 E1:1 to set them to extrude equal amounts.

Ah yes, forgot to mention the mixing ratio - thanks for putting that right David.

Spodeopieter

@briskspirit @dc42 @deckingman Thanks for helping me out !