@droftarts they have a section in their assembly instructions specifically for the 6HC that said to use io2.
I figure they just copied over the mini instructions without actually testing it beforehand.

@deckingman thank you for your explanation much appreciated.

@deckingman That's a bit odd, because in the web interface it shows controls for both, and if i change the one fan slider, it changes the other slider a second later.
Same thing when the gcode changes the fan speed, the web interface's 2 sliders both change.
It also "sounds like" it's changing both, but I could be mishearing it, and I cannot verify visually.
On the web interface on PC is two buttons that switches between the fan you want to change speeds for. Clicking back and forth shows no difference in value. On mobile web interface you can see two sliders, and they both change. Just to make sure I'm describing it properly.
You are correct that it says "tool fan" and "Layer fan".

(I have the newest stable firmware and web control)

I have a duet3 6hc on a v-core printer.

My fans are configured like this:

M950 F0 C"out7" Q500                   ; create fan 0 on pin out3 and set its frequency
M106 P0 C"Hotend Fan" S0 H1 T45 L255   ; set fan 0 name and value. Thermostatic control turned on for Hotend
M950 F1 C"out4" Q500                   ; create fan 1 on pin out4 and set its frequency
M106 P1 C"Layer Fan" S0 H-1		       ; set fan 1 name and value. Thermostatic control is turned off

I have noticed that my slicer's gcode doesn't specify which fan to change speeds on, so both the fans are changing speeds. Is this working as intended?
I would have thought that when you ask the slicer to do more or less cooling on bridges, for instance, it is the layer fan you would like to have fan speed change on?
Is there a way to achieve this?
Also I thought the L255 parameter made the fan for the hotend run at max speed when turned on, so I'm clearly misunderstanding something.

Thanks for your time.

@droftarts
You were correct. I took the motor out of the orbiter and tested. It turned happily when no extruder was attached.
Opened up the planetary gears and did an inspection. Everything looked well lubed and turned easily.
Put it together again, and now it spun as it is supposed to.
Thank you

About the 1.2A - no, it doesn't get hot. It's in the documentation for the unit, so I hope they know what they are doing.

Hi guys.
I got myself a headscratcher I can't really figure out.

My problem is that when I try to extrude, I can extrude about 4mm, and then the motor starts buzzing, and stops extruding/turning. If I then try and retract, I can retract about 4mm and then then the buzzing starts again.

I have this setup
Board: Duet 3 MB6HC (MB6HC)
Firmware: RepRapFirmware for Duet 3 MB6HC 3.4.4 (2022-10-20)

The documentation for the Orbiter 2.0 states the following Gcodes needs to be set for Reprap firmware.
I put them last in the config.g file so I'm sure they will be set, in case I accidentally set something above that could overwrite.
The config.g file is also attached in case there is something relevant.config.g
M350 E16 I1
M92 E690
M203 E7200
M566 E300
M201 E10000
M906 E1200 I10
M572 D0 S0.02
M207 S1.5 F7200 Z0.2

I have heated the nozzle to 200 and have pla on the spool. I can push some through by hand, when pushing in the lever.

The Orbiter 2.0 didn't come with a connector that was correct for the board, so I had to crimp one myself. I'm fairly certain the order of the wires is correct, because it does move the filament forward when i tell it to extrude, and backwards when I retract (until buzz-stop)

Anybody have an idea, or know what I should read up on?

@stephen6309 That worked a treat. Thank you both for your help you are real human beans.

@stephen6309 oh. I was nervous about the partition I couldn't read containing important files. Performing the reformat as we are speaking.

@gloomyandy I am using the duet 3 board with a sd card plugged directly into the board. there is no raspberry pi machine connected to it.
Sorry if I haven't been clear on that.

@stephen6309 Dang it. I hoped it wouldn't be a big overhaul. Thanks for taking time out of your day to help me.

@stephen6309 Uh. I'm getting a "connection refused" error. when i SSH to the IP of the duet board.
is that a setting i have to enable in a file on the SD-card?