Circles coming out jagged

Festivejelly

Ive updated my firmware on my duet 2 wifi so that I could use an accelerometer.

All seems to be going okay except circles are being printed all jagged, like it cannot handle doing curves. I thought RRF had arc support?

Its very odd because essentially on any curves it prints them all jagged.

In the slicer it looks absolutely fine, no weird segmentation. Any ideas? Could it be the duet cant handle the speeds/accel? im going around 150mm/s

Festivejelly

Jerk and acceleration settings

M350 X16 Y16 Z16 I1 ; Configure microstepping with interpolation
M566 X300 Y300 Z8 C2 E200:200:200:200 ; Set maximum instantaneous speed changes (mm/min)
M203 X35000 Y35000 Z600 C5000 E5000:5000:5000:5000 ; Set maximum speeds (mm/min)
M201 X4000 Y4000 Z100 C500 E4000:4000:4000:4000 ; Set accelerations (mm/s^2)

Version 3.5.0 RC2

jay_s_uk

@Festivejelly your z jerk is stupidly low. Don't forget it's in mm/min so 8 would be 0.13mm/s

Festivejelly

@jay_s_uk Im not seeing a problem on the Z but thats an interesting observation.

Festivejelly

@jay_s_uk Its based on part on this: https://github.com/Duet3D/RRF-machine-config-files/blob/master/E3D_Tool_Changer/dc42-duet3-centreZero-2Titan-2Hemera/sys/config.g

Always worked fine for me in the past.

gloomyandy

@Festivejelly Can you post an example of a circle and perhaps the gcode used to produce it.

Festivejelly

@gloomyandy Ill try and create generic one as I cant share the Gcode for the actual objects. But I do wonder if its a quirk of Bambu Slicer as ive been using that as it allows to print walls inner out inner.

Im going to slice the file in Prusa Slicer and see if it has the same issues,

Phaedrux

@Festivejelly said in Circles coming out jagged:

@jay_s_uk Im not seeing a problem on the Z but thats an interesting observation.

If you have mesh compensation active, Z would certainly play a part.

Your X and Y jerk are also very low. Circles are still made up of segments.

I think you should test with X Y and Z jerk set to 600 and see if it improves.

Festivejelly

@Phaedrux I'll give that a shot, they were always fine that low in the past but i'll give it a shot if not just to rule it out. Ive also increased the Z jerk

Phaedrux

You don't mention your firmware version, but recent changes in pressure advance and input shaping may also have an impact on jerk.

What firmware were you on before, and what firmware are you on now?

Festivejelly

@Phaedrux I think it was 3.4.3 ill need to hunt around in my files but I dont think the binaries are named by the version so might be hard to tell.

I upgraded the version to use the duet accelerometer which ended up being a dud anyway, wish id stayed on the version I was on!

Ive rolled back to an older firmware version and it seems to be printing better now but the ringing is all over the shop even with input shaping. I wonder if the input shaping is actually causing this.

Im not entirely confident in the input shaping values from the sensor tbh.