Extra bit apparently added by OctoPrint

Hi All,

TLDR= Octoprint is adding a bit extra to the print, need to stop it from happening.

Was scared to try it at first, not wanting to mess with the factory settings of the printer...(ie firmware) but I realised quite early on that it's easier than I thought and it is fabulous!
I've been using Octo for a while now, pi zero 2, and it's brilliant, so well done to all involved, thanks.

Anyway, just recently I have noticed an interesting oddity has appeared in all my prints.
One of the corners of each object gets an extra tiny diagonal line printed so the edge isn't square anymore.

Elimination tests:
It's not in the original gcode from the slicer (creality 4.8)
It's not added by the slicer (tried creality later version)
It's not there if I load up the gcode into mainsail (not using it because I have marlin stock firmware).
The models almost exclusively come from tinkercad, and usually involve simple rectangles (yes, I'm not very imaginitive).
I've also tried a fresh build, new pi zero-2W / new sdcard / newly formatted from Pi firmware writer / loaded, updated, no plugins. Loaded up a fresh STL file from tinkercad & there is is.
It looks like this in the mainsail gcode viewer Imgur: The magic of the Internet - not there.
It looks like this in octoprint Imgur: The magic of the Internet - there it is - little diagonal line.
The extra diagonal line at 45 degrees is actually being printed, so once finished, it needs to be shaved off again. It's a fraction of a mm but there.

I've googled it but not found anything, which surprises me.
Can't really read the gcode to confirm manually that it's not there in the original, but mainsail shows it's not there...
I've tried all the elimination tests I can think of to remove variables, hence the fresh install.
I'm clearly missing something - or I am doing something wrong.
Please help !
thanks in advance, much appreciated.

You sure those aren't travel moves? Can you share a gcode file? I think you're seeing that because of the options selected in GCode Viewer tab.

image

Green lines are travel moves, they are not printed but moves the head does without extruding. See also the retract symbols at the start and end.

jneiliii is right. Those are travel moves. If it actually lays down any filament, that would be a stringing event and you need to do a little more tuning.

Ooh that's interesting, thanks for mentioning it.
Isn't it coincidental that it's the same place as the extra fuzzy bit...?

So the question changes then...
Why am I getting one fuzzy corner on my prints?

I guess I'll have a go with the sd-card then...that's the only remaining variable, before asking the question elsewhere...

Thanks, (I think).

As CmdrCody pointed out, you probably need to tune your settings more, specifically temperature and retraction. Here's a good reference guide on calibrating slicer settings: https://teachingtechyt.github.io/calibration.html. What is happening more than likely is your retraction isn't large enough to reduce the backpressure on the nozzle causing oozing of the filament out of the nozzle as it travels.

Now if you watch it while it's printing and it gets to that corner and is pausing slightly than that could be firmware buffer being too small or possibly a plugin. If you haven't already you should try running OctoPrint in safe mode to validate that any installed plugins aren't causing stuttering.

Another thing could be you didn't turn on Random Seams and every layer starts and stops in that same corner. That will put all the over/under retraction at the same point which will blob out a corner in no time.

Hiya

That's a really helpful insight into the workings, thanks.
I will try & do that...

Hi Foosel,

I read your post & it sounded very plausible, thanks - hence my earlier reply to go away & look elsewhere.

However, on reflection (having slept on it & remembered when it started a couple weeks ago) I remembered that those little green lines started about halfway (ish, not exactly) up the print, not the whole height of the object.

They green lines did indeed coincide with the extra blob, maybe it is stringing, but why wouldn't it be concistently adding those travel lines in the same place each layer I wonder?

The other layers didn;t have the little green "travel" lines in the corner and didn't have the extra blob.

At this stage it's a an oddity which I'd like to sort out, it's not stopping printing of utilitarian objects but it has a huge bearing on aesthetic objects...

BTW - as per the original post, I tried a brand new install of octoprint, & it's the same so definitely not a plugin causing it.

Hi jneilliii

Wow that's really interesting, thanks, I wondered what those triangle were!
You're absolutely right - those are indeed "moves" which show up.
Without those two boxes ticked, it's exactly the same view as mainsail, which makes perfect sense, thanks.

I'm quite intrigued as to why they are where they are, because they're outside the print object.

So if thats the case, and they are moves, which should have retracted, and they're depositing filament, then that's wrong & sounds like I need to look at retractions etc - or changing slicer!

Thanks
I might update in a week or two after some experimenting...
keep up the fab work.

very slicer and slicer setting dependent. some slicers offer more control over that kind of stuff than others. might want to look at the do not cross perimeters setting (can't remember exact name). switch your seam to random and you'll see a bunch of random travel moves all over the place.