This has a been a recurring problem for me, and I have no idea what parameters are causing this. Often times, when there is a vertical wall, these patterns will appear, often in the exact same spot for the same print, so its likely a slicer-side problem. Also, no pattern will appear on the opposite, but mirrored side. It seems to stem from the fact that one layer will have gaps in the wall, and then for the next layer, material can only be deposited on top of that same spot. Does anyone have any idea what settings I can change to get rid of this problem?

Weird patterns on side of print

Weird patterns on side of print

Weird patterns on side of print


June 9, 2019

Protolate Protolate
Beginner
2 posts

6 replies


This is the pattern you get with persistent underextrusion. The cause can be a partial clog, in that case your extuder is clicking periodically and you can see the cog skipping back. The filament can slip in the extruder because of not enough grip, then you get no clicking. Or can be simply badly set up slicer, for example when you do not set up the filament diameter correctly.

June 9, 2019

psanyi psanyi
Exalted
945 posts

It also could be an issue with your stepper motors. See this blog page for details about this: Smoothing Stepper Motor Movement

June 11, 2019

Birk Binnard Birk Binnard
Exalted
704 posts

I have a similar problem on the CB3. At first I thought it was an extruder problem. It wasn't. Then there is the old "clogged nozzle" since the CB3 measures that and claims its clogged. It wasn't. Then I thought maybe the ribbon cable was faulty because the problem always occurred on the far corner of the print. But I don't think that is the problem either.

So that leaves Craftware or the firemware. I suspect the firmware is having some problems converting gcode to movements under some circumstances. Don't know but we will see.

June 12, 2019

Allen67 Allen67
Beginner
36 posts

If you have a precise scale, you should weigh the part and compare it with the weight it should be given the amount of filament in it. I'm guessing it is way lighter. Google for "100g jewelry scale" to see what I mean.

June 13, 2019

psanyi psanyi
Exalted
945 posts

I think I and everyone here assumed this was some type of hardware problem. IT ISN'T. First, maybe it was the extruder not working well. Nope. Then I thought it was the ribbon cable maybe disconnecting because this was occurring when it was stretched. NOPE. I did lots of troubleshooting and its not that.

So there is only two things that might be causing it for me, Craftware or the printer firmware. In a day or so I will know which. I strongly suspect, a firmware problem.

I have been doing testing printing the same model multiple times, and the defects are the same at the same point in the model, every time. I've looked at them with high magnification. The CB3 also has a filament monitoring system that seems to detect "nozzle clogs" at the exact same time in a print over and over. I have videos showing this. I highly doubt that a nozzle would clog EXACTLY at the same time over and over. And maybe 30 or 40 clogs during a print? Each time the Craftbot can magically clear these "clogs."

So I would not get to occupied with trying to solve a hardware problem, because at least on my printer, its clearly a software/firmware problem.

UPDATE: After a bunch of printing using Simplfy3D, I am now very certain that the print quality problems I was having were due to Craftware, NOT the Craftbot 3's firmware. If you are having print quality problems, try a different slicer.

Not only was the Craftware gCode causing quality problems (and on a Mac when it even runs) the gCode was also triggering the CB3 filament monitor to "detect" a clogged extruder that was never clogged. This would occur OVER and OVER. With the Simplify3D version, not one clogged nozzle problem on the whole print, like I would expect.

Maybe instead of producing Craftware, maybe CU could spend some time making profiles for other slicers. Just a thought.

June 13, 2019

Allen67 Allen67
Beginner
36 posts

Try a different slicer and report back if that doesn't solve your problems. I've printed things in Craftware and then Simplify3D, and the difference is night and day.

June 14, 2019

Allen67 Allen67
Beginner
36 posts
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