Texture on print surface

AndreasDesmedt

Hi all!

Cool forum! Helped me a lot in setting up the Duet and building my Delta printer. I'm in the last stage of getting my new delta printer fully up and running. Everything is working well and quality is extremely good so far, with the best I've seen on any of my machines. But there is one tiny thing that I have noticed.

When printing parts with straight up walls, it seems ther is some sort of pattern or texture on the surface of the print. It's delta related, because it is less on movements where only 2 axes are moving. It's super fine and you can't feel it, but it's noticeable when you hold it under bright light. Has anyone had this happen and know the fix? I'm running 0.9° steppers with x16 microstepping, interpolation on. I've been thinking about vibrations from the belt but I wanted to check here first before I begin to change everything.

https://imgur.com/0PHLv2u

Another small question: what are the variations the Duet uses when doing auto calibration and automatically changing radius, Endstop offset,...? The IR probe on my delta has a pretty consistent trigger height, so every point where it triggers is pretty much the same nozzle height, only problem is that my glass bed is not flat. So the trigger height does differ, but the distance from the nozzle to the bed is always right. Made me wonder if that gives problems when doing auto calibration, does the firmware know that it is a bed variation and not a variation in radius? How is it able to split up these things, or isn't it?

Thanks in advance!

Andreas

Phaedrux

That looks a lot like the infill pattern showing through. Could that be it?

AndreasDesmedt

Can't be an option as it's a perimeter-only print.

AndreasDesmedt

Anyone?

dc42

Are you certain that there is no infill between the inner and outer perimeters?

AndreasDesmedt

@dc42 said in Texture on print surface:

Are you certain that there is no infill between the inner and outer perimeters?

Nothing, 100% sure. I figured out the lines are spaced about 2mm from each other, wich makes me think it's indeed a belt problem. I'm running toothed idlers, will switch to smooth ones with a twisted belt. Will also replace belts and pulleys to better quality ones and check again.

dc42

Toothed idlers should be OK, I use them on my delta and I don't see any banding.

Is the vertical pitch of the banding 2mm, or some other value?

AndreasDesmedt

@dc42 said in Texture on print surface:

Toothed idlers should be OK, I use them on my delta and I don't see any banding.

Is the vertical pitch of the banding 2mm, or some other value?

It indeed is, lines are 2mm spaced from each other vertically. But like I said, it's barely visible and can't be felt, but under strong light they show up.

The parts where only 2 out of the 3 carriages move have less of these lines. Wich probably proves it is an XYZ motion problem.