Strange Blobbing on Layer Change

Phaedrux

@davidewen said in Strange Blobbing on Layer Change:

I've increased jerk in PrusaSlicer to the following;
X: 32
Y: 32
Z: 32
E: 20

Where did you change that?

I assume that's in mm/s?

Does prusa slicer now allow per move jerk settings as well as acceleration? I didn't think so.

Is your prusa slicer set to RepRap gcode flavour?

Can you share a sliced gcode file?

Your config file still has the limits set very low, so unless your slicer is actually sending M566/M203/M201 commands to change the limits during a print you are being limited by the config.g

Norder

@Phaedrux

Does prusa slicer now allow per move jerk settings as well as acceleration? I didn't think so.

The PrusaSlicer has its own jerk setting (mm/s), maximum acceleration (mm/s²) and maximum feed (mm/s)
for each axis.

Phaedrux

@Norder said in Strange Blobbing on Layer Change:

The PrusaSlicer has its own jerk setting

Where? You mean in the machine limits?

Norder

@Phaedrux
Yes, exactly.
But it is clear that the upper limit is determined by the config.g.

davidewen

@Norder @Phaedrux @weed2all

Thank you all for responding.
I will not be able to check settings or respond back with said settings until late next week.

Cheers

davidewen

@Phaedrux

Yes, I made those changes in PrusaSlicer.
Are you suggesting that I make the changes in config.g?
And if so, is that command M566?

My current M566 is not labeled "jerk" so I just want to confirm.

M566 X1500.00 Y1500.00 Z600.00 E120.00			; set maximum instantaneous speed changes (mm/min)

M203 X12000.00 Y12000.00 Z600.00 E2100.00		; set maximum speeds (mm/min)

M201 X1500.00 Y1500.00 Z500.00 E250.00			; set accelerations (mm/s^2)

Phaedrux

Yes, maximum instantaneous speed changes is often called jerk.

davidewen

@Phaedrux

Got it. Do you have some recommendations from my current settings?

Phaedrux

@davidewen Try these

M566 X1500.00 Y1500.00 Z600.00 E3000			; set maximum instantaneous speed changes (mm/min)
 
M203 X12000.00 Y12000.00 Z600.00 E6000		; set maximum speeds (mm/min)
 
M201 X1500.00 Y1500.00 Z500.00 E3000			; set accelerations (mm/s^2)

davidewen

@Phaedrux
Thanks for the info. This has helped a lot. Seam is still there, but greatly improved.
I will play around with these settings to see if I can get it to almost perfect.

Cheers!

Phaedrux

@davidewen said in Strange Blobbing on Layer Change:

Seam is still there, but greatly improved.

Have you tune pressure advance yet? That's the remaining piece of the puzzle.

https://docs.duet3d.com/en/User_manual/Tuning/Pressure_advance