Duet 2 WiFi/Ender 3 rounded/bulging corners

I recently got into the RepRap world with the Duet2 wifi on my Ender 3 Pro(glass bed and converted to direct drive before changing) and ever since then I’ve been having issues with corners coming out rounded/bulging. I copied the exact settings from the old board running Merlin(prints were perfect) and the prints just won’t come out the same.

Stock settings

Acceleration - X500 Y500 Z100 E5000
Jerk - X600 Y600 Z18 E300 (mm/min)

I dialed in the extruder steps/mm but I just keep getting this weird curved corner.

So far I’ve tried dialing in pressure advance and messing around with speed/jerk/accelerations and nothing helps.

Here you can see the issue on the corners. The white and blue were old prints from Marlin and it seems they are way better
[m.imgur.com]

I’m not sure what else to try

X and Y acceleration seem pretty low. If you set it higher do layers start shifting?

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I tried up to 2000 for X and Y, no skipping but it didn’t seem to help either. I’m printing a single walled square at 50mm/s all the way down to 10mm/s and it’s the same result. Nothing was changed except for the board. I’m out of ideas lol

It's a mistake to try to compare prints when you change multiple things at once. In this case you have changed both the controller and the filament.

On the black Y cube, it's obvious that you have severe ghosting, almost certainly caused by ringing. If the Y face was printed parallel to the Y axis, that might be caused by a loose X belt, or the X motor current being set too low.

You may have inadvertently changed the following when you upgraded the controller:

- Motor currents. If your previous controller used tiny pots to set the current, you can only know what the currents were if you measured the voltages and you know the value of the sense resistors on the driver boards.
- Hot end temperature. If you know exactly what temperature table your hot end thermistor used under Marlin, we can replicate the temperatures in RRF. Otherwise, it's anyone's guess. AFAIK nobody has done details measurements of how those "100K NTC B3950" thermistors behave at printing temperatures. The B value is only valid at lower temperatures, typically it is quoted between 25C and 75C.

Did you follow the guide at [duet3d.dozuki.com] ? It was written for users upgrading to Duet Maestro, but almost all of it applies to Duet WiFi too.

HTH David

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].