@chrishamm Thanks for the very quick reply! Just to confirm I should be building it with the Duet3_MB6HC_no_SD configuration?

I was hoping to play with some firmware features. I have built Duet3_MB6HC_no_SD for project RepRapFirmware. I note that there are update instructions when it is not in SBC mode. But the SBC mode setup does not mention anything about uploading custom firmware. Can I still just upload the firmware via DWC? I see there is an "Upload Firmware Files" button and I have built a Duet3Firmware_MB6HC.bin. Also should I be using the Duet3_MB6HC_no_SD configuration or the Duet3_MB6HC configuration? I assumed the first since the SD card is in the connected Raspberry Pi.

@deckingman Yes this could well be it.

@droftarts Nice idea but unfortunately the Y axis is longer than the X axis in machine.

I will get myself a new lead screw.

@o_lampe I first just checked against a ruler and saw that over distance the bad lead screw threads were not lining up to the ruler over a longer distance. A CAD model was available for the lead screw. I generated the "negative" of it and 3d printed out a 200 mm segment. As I expected it snapped right on all my good lead screws but if I tried to snap it on to the bad lead screw it did not work and I can easily visually verify that falls out of alignment. I feel this is enough proof for me.

I am rather sure that one side is not loosing steps. This would be the good side and it looks to be very accurate. I think I will wait for a replacement lead screw. While it would be nice to be able to compensate for this I can see it being a low priority feature! Best for me to start with the right hardware.

I recently assembled one of the WorkBee CNC derivatives. The Y axis uses two motors. The Low X side of the Y axis seems to be very accurate. The High X side of the Y axis looks to be off due to what I measure to be a slightly stretched out lead screw. Every 400 mm the High X side moves one extra mm. I am going to replace the lead screw. In the mean time I was wondering if it was possible to compensate for this in the config? No commands are jumping out at me. If I could get the motor on the High X side of the Y axis to step just a bit slower than the other one then I would have a workaround

The relevant part of my config.g:

; Drives
M569 P0.0 S1                   ; physical drive 0.0 goes forwards
M569 P0.1 S0                   ; physical drive 0.1 goes backwards
M569 P0.2 S0                   ; physical drive 0.2 goes backwards
M569 P0.3 S1                   ; physical drive 0.3 goes forwards
M584 X0.0 Y0.1:0.2 Z0.3        ; set drive mapping
M350 X16 Y16 Z16 I1            ; configure microstepping with interpolation
M92 X400.00 Y400.00 Z400.00    ; set steps per mm
M566 X900.00 Y900.00 Z300.00   ; set maximum instantaneous speed changes (mm/min)
M203 X6000.0 Y3000.0 Z2000.0   ; set maximum speeds (mm/min)
M201 X500.00 Y250.00 Z100.00   ; set accelerations (mm/s^2)
M906 X2400 Y2400 Z2400 I30     ; set motor currents (mA) and motor idle factor in per cent
M84 S30                        ; Set idle timeout

Thanks for all the information! I'll take a poke at the M584 code. As of know with all my plans I can live the axes starting and stopping at the same time. I would see myself just manipulating one at the time in a simple fashion. Just starting out to experiment a bit with the hardware side of things. The planned RRF 3.5 features sound exciting.

I am looking to use my Duet 3 to control some linear actuators that help automate some things in my workshop. I was wondering if I can configure things so that I can just add arbitrary axes rather that use some existing machine profile like Cartesian or whatnot.

As of now I wired my stepper and endstop to the Duet. I configured things so that they are just controlled via the x axis. This all works great. However, the intended application for this axis is to set the height of a platform precisely. Preferably I would be able to just give it a name that reflects its purpose. Is there anyway to do this or am I locked to the predefined "architectures"? I would like to add further arbitrary axes over time to deal with other little tasks.

I don't mind doing a little coding to accomplish things. I guess a workaround for me would be to write a little plugin for the web interface to give me a panel that looks how I want it to.