Printing stop momentarily

engikeneer

@Rattlemycage if you are not using bed mesh compensation, it could also be that you have your slicer set to 'Lift Z' on a retract?

My Zaxis settings are: 75 mm/min Jerk & 200 mm/s^2 accel

I have 3 Z-motors wired in series to the Duet so can't run them very hard/fast - they used to be faster/higher accel/Jerk when I only had 2 Z-motors. When setting these, I just kept adjusting the numbers whilst moving the Z axis up and down ~20mm until I found the limit where the Z- motors would start skipping steps. I then set my Jerk/Accel to be a bit less than that to be on the safe side.

Other thought, It could equally be your extruder motor settings causing slow retractions (exactly as with the Z-axis) as these look a little low (depending on your setup). Try increasing the extruder Jerk and Accel settings and see if that helps.

On either of these, your motor currents are all set at 800mA. Not sure what your motors are (so check what their limits are!) but you could go higher to get more torque and so allow higher accel and jerk values.

For all of these, just update the numbers in right lines the config.g file via Duet Web Control, save it and reboot the Duet. Whilst tuning, you can temporarily tweak them by sending the relevant comands via the G-code command line in DWC

Rattlemycage

Thank you so much for your assistance.

Phaedrux

@Rattlemycage said in Printing stop momentarily:

M566 X900.00 Y900.00 Z22.00 E120.00:120.00 ; set maximum instantaneous speed changes (mm/min)
M203 X6000.00 Y6000.00 Z280.00 E1200.00:1200.00 ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z40.00 E250.00:250.00 ; set accelerations (mm/s^2)

These are the lines you would edit by the way.

Also, what slicer are you using? Could you share a video of the behaviour?

dc42

Are you printing the file from the built-in SD card, or some other way (e.g. via USB or an external SD card)?

Rattlemycage

I am printing the file via the Duet Web Control 2.0.4

The slicer is Simplify3D.

When the head stops it leaves small blobs of filament.

Rattlemycage

I increased the speed. without success. Still stopping. What am I missing guys?

; Drives
M569 P0 S1 ; physical drive 0 goes forwards
M569 P1 S1 ; physical drive 1 goes forwards
M569 P2 S1 ; physical drive 2 goes forwards
M569 P3 S1 ; physical drive 3 goes forwards
M569 P4 S1 ; physical drive 4 goes forwards
M584 X0 Y1 Z2 E3:4 ; set drive mapping
M350 X16 Y16 Z16 E16:16 I1 ; configure microstepping with interpolation
M92 X80.00 Y80.00 Z800.00 E415.00:415.00 ; set steps per mm
M566 X900.00 Y900.00 Z200.00 E120.00:120.00 ; set maximum instantaneous speed changes (mm/min)
M203 X6000.00 Y6000.00 Z2000.00 E1200.00:1200.00 ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z250.00 E250.00:250.00 ; set accelerations (mm/s^2)
M906 X800 Y800 Z800 E700:700 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S10 ; Set idle timeout

; Axis Limits

deckingman

@Rattlemycage Does this momentary stopping coincide with a layer change, or with a retraction, or is it seemingly random? Can you make and post a video of it happening?

Rattlemycage

@Rattlemycage, It is seemly random. On a single layer of an object perimeter, say 4 inches by 5, it might actually come to a stop 7 or more times. I tried to upload a video but my files are larger than the 4mb permitted.

Phaedrux

For larger files you will need to host them on a file sharing cloud platform like dropbox or google drive or vimeo or youtube.

Can you also share the sliced gcode file itself?

Your E speeds are still quite slow at 1200mm/min. That would restrict your retraction speed to 20mm/s. If you have a longer retraction move that can lead to a noticeable pause at travels and layer changes.

A low E jerk can also cause slow downs when used with pressure advance, but I don't see pressure advance command in your config.

I would suggest trying these speeds

M566 X900 Y900 Z200 E3000:3000 ; set maximum instantaneous speed changes (mm/min)
M203 X6000 Y6000 Z2000 E6000:6000 ; set maximum speeds (mm/min)
M201 X2000 Y2000 Z250 E3000:3000 ; set accelerations (mm/s^2)
M204 P500 T2000 ; print and travel move acceleration

I've removed the .00 to make it more legible. And added the M204 command to have seperate print and travel move accelerations which should speed up travel moves quite a bit which can help blobbing as well. (assuming the blobbing is on retractions.)

Rattlemycage

Thank you for all your assistance. I feel rather embarrassed to ask for more.
I have the settings for my machine.

Printing Acceleration 1000.00 mm/s2
Retract Acceleration 3000.00 mm/s2
Travel Acceleration 1000.00 mm/s2
Max Acceleration X 9000.00 mm/s2
Max Acceleration Y 9000.00 mm/s2
Max Acceleration Z 100.00 mm/s2
Max Acceleration E 10000.00 mm/s2
Max Jerk X/Y 12.00 mm/s
Max Jerk Z 0.40 mm/s
Max jerk E 5.00 mm/s

How do i put these values in my config.g please?

Thank you

Phaedrux

@Rattlemycage said in Printing stop momentarily:

How do i put these values in my config.g please?

Well you must first edit the config.g file either on the web interface or on the SD card directly.

https://duet3d.dozuki.com/Wiki/Duet_Web_Control_Manual

The values you want to edit are the ones I pasted above. Bear in mind that the values you posted are from marlin and are in mm/s and RRF uses mm/min, so note the units being used.

I would still recommend the values I posted.

M566 X900 Y900 Z200 E3000:3000 ; set maximum instantaneous speed changes (mm/min)
M203 X6000 Y6000 Z2000 E6000:6000 ; set maximum speeds (mm/min)
M201 X2000 Y2000 Z250 E3000:3000 ; set accelerations (mm/s^2)
M204 P500 T2000 ; print and travel move acceleration