Tips to mitigate vertical artifacting Duet 2 Wifi

fcwilt

Try varying the belt tension to see if has any effect.

Frederick

Phaedrux

Belt teeth on smooth idlers, or even belt teeth on small diameter toothed idlers can be a factor. It also looks a bit like regular ringing. What are your other print parameters? Post your config.g and slicer settings.

What does it look like with a regular ringing test print?

theruttmeister

Try printing your outer perimeter at really low speeds.

That looks like cogging, which tends to be speed dependent.

Basically stepper motors have speeds where they are stable, and speeds where they are less stable (related to things like winding, size, voltage etc). When its in an unstable speed range it will 'jump' between full/half steps, rather than moving smoothly between the steps.

I have a printer that at 80-90 mm/s does it really badly. But if I print the outer perimeter at 20-30mm/s you would never know. And solid surfaces don't show it for some reason.

If you are having steppers manufactured they ask what speed you plan on running them so they can design a winding to minimize cogging at that speed.

The other thing that seems to help is using bigger motors and under-driving them.

brotherchris

@Phaedrux I thought about crossing the belt's I might try that. Config and slicer profile attached. I will print a ringing test. slicer settiongs.gcode config.g

brotherchris

@theruttmeister Great info, this is 15mm/s.

Phaedrux

That's looking a bit cleaner. Is that a faint diagonal I see or is that an artifact of the image?

A good way to test what @theruttmeister is talking about would be to reprint that object sliced at 100mm/s and then using the speed factor to change the speed by 10mm/s every 10 layers or so.

brotherchris

@Phaedrux Yeah, it's 45 degree striping. I will try it faster.

brotherchris

More pic of the stripes. Reminds me of old school A4988 candy strips.

Phaedrux

For the sake of completeness can you provide your config.g, the results of M122 and M98 P"config.g". Maybe some more details on the printer.

brotherchris

@Phaedrux Sure, I posted config.g above, but I can do it again. config.g m122.txt 10/2/2020, 9:23:33 PM M98 P"config.g"
Warning: Heater 0 appears to be over-powered. If left on at full power, its temperature is predicted to reach 265C

The printer is an EXO cube, almost just like this one.
https://www.exoslide.com/exocube-printer

Phaedrux

@brotherchris said in Tips to mitigate vertical artifacting Duet 2 Wifi:

@Phaedrux I thought about crossing the belt's I might try that. Config and slicer profile attached. I will print a ringing test. slicer settiongs.gcode config.g

Sorry I missed those before.

Nothing stands out as obvious in the config.

Which leaves us with mechanics and the minutiae of stepper drivers.

brotherchris

@Phaedrux said in Tips to mitigate vertical artifacting Duet 2 Wifi:

minutiae

Totally agree, I am pretty used to troubleshooting these types of things. I have seen this before, but never on a 2660 driver. This post was mainly to see if any other Duet users were seeing this. Great discussion by the way, enjoying it.

Phaedrux

You might find this interesting: https://duet3d.dozuki.com/Wiki/Tuning_Stepper_Motor_Drivers

Not sure how applicable or helpful it would be in this case though.

brotherchris

@fcwilt Thanks for the reply, Left is normal, right is super tight belts.

brotherchris

@Phaedrux Ringing test.

Phaedrux

Might be able to reduce the ringing a bit with a drop of jerk from 1200 to 700.

Hard to say if that would be enough to fix the benchy artifacts.

fcwilt

@brotherchris said in Tips to mitigate vertical artifacting Duet 2 Wifi:

@fcwilt Thanks for the reply, Left is normal, right is super tight belts.

I wish I could remember exactly what I did to fix the problem. It was awhile ago when I had a CoreXY of my own design.

Frederick

Veti

i switched to 0.9 degrees stepper and 16 tooth pulleys.

see
https://forum.prusaprinters.org/forum/original-prusa-i3-mk3s-mk3-user-mods-octoprint-enclosures-nozzles-.../stepper-motor-upgrades-to-eliminate-vfa-s-vertical-fine-artifacts/

brotherchris

Latest print, the 0.9 degree steppers are my last resort. I think I have exhausted most of my other ideas. I will switch them out today and report back.

NexxCat

Sorry, kinda off topic, but just put 2+2 together and realised @brotherchris was Chris Riley. Love your videos, keep up the fab work