What's going wrong here

[xyleth]

The prints work, but they sure don't look pretty.  I'm not sure if it is an intermittent clog or extrusion failure or?

Voron 2.4, Revo Obxidan HF 0.4 nozzle.  0.24 layer height, Jayo PLA Meta @ 195C print temp.

[Dirk]

I doubt it is a clog.

Is obxidian not the super expensive nozzle for the even more expensive revo hotend?

I would suggest you tune your settings better for this plastic.

I would start with Ellis' guide and do the extruder calibration, it will also show any clogs or extruder failures. Then do a temperature calibration for that filament, Pressure advance and extrusion multiplier tunings. 

I would also suggest looking at if your coolings for your printer for pla is sufficient.

What I can see the top layer, the layers are not adhering and kind of wavy, so either your plastic is not melted enough (requiring higher nozzle temperature) or you are going too fast for it, that it is bothered before it has cooled down.

 

For further tuning of this problem, check out the topics cooling and layer times (the images are illustrative) and perimeter separation

 

 

 

 

Edited May 20, 2024 by Dirk

[xyleth]

Yes, it is the fancy nozzle.  The idea was to only have to have one set of nozzles regardless of if I'm printing abrasives or not.  Plus the Obxidian coating reduces plastic sticking to the nozzle during printing which was attractive, especially so with PETG.

I have been through the Ellis guide with this filament on this printer.  I wouldn't have asked for help if I hadn't at least done the basics . I thought I had got it dialled in, but clearly not.

This part was one of a batch of 5 printed together which all suffer from the same defect in roughly the same place.  The plastic has plenty of time to cool while the head is off printing the next part in the batch so I don't think it's that.

I also have the same part printed in the same plastic (same reel!) with the same settings and it has none of these issues.  The only difference is that was printed as a single item not as a batch.

[Dirk]

37 minutes ago, xyleth said:

I wouldn't have asked for help if I hadn't at least done the basics 

You wouldn't have been the first one if you had

So if you have gone through all those obligatory steps, you will know more about your extruder and nozzle and its ability.

38 minutes ago, xyleth said:

The only difference is that was printed as a single item not as a batch.

This is more informative.

Since it is the same layer height where you are having the problem, there might have been a problem with your plastic at that moment, like you suggested a partial clog, but I would first think an irregular part in the filament.

Another thing to consider is still the heat produced in the printer. Do you do anything to remove excess heat, like opening the doors, removing panels? This could cause the cooling to be too slow when printing pla.   Even the layer time is high.

 

 

 

 

 

 

So if you have 

[xyleth]

4 minutes ago, Dirk said:

You wouldn't have been the first one if you had

I know, but I strive not to be 'that guy', you know?

5 minutes ago, Dirk said:

Another thing to consider is still the heat produced in the printer. Do you do anything to remove excess heat, like opening the doors, removing panels? This could cause the cooling to be too slow when printing pla.  

The lid and the door of the Voron enclosure are off for PLA printing, the sides are on.  Bed is at 60C.  The Stealthburner part cooling fan is set to run in a range between 50 and 70% during regular printing as determined by the slicer (Orca), with 100% reserved for bridging.  The default is to run the part cooling at 100% all of the time.

The other part I have printed in this plastic is the frames that those twist locks hold together.  These are large, flat pieces and come out okay:

 

There is some weirdness though, after the first layer is down on the subsequent solid bottom layers a similar artefact appears where extrusion just seems to stop for one pass of the pattern:

If it is a transient clog it is remarkably good at resolving itself for the next line.  The next layer above goes over and it doesn't have any impact on the finished part I can tell, and once the infill starts it seems fine.

Max speed for solid infill is 200mms.  Outer walls 120, top surfaces 100.

[Dirk]

That last picture is informative. Like you say it looks as if it doesn't extrude for a whole line.

This would point more in the direction of your extruder. 

But it wouldn't explain why the single parts come out ok.

I would take a look at the extruder.

[claudermilk]

1 hour ago, xyleth said:

I know, but I strive not to be 'that guy', you know?

The lid and the door of the Voron enclosure are off for PLA printing, the sides are on.  Bed is at 60C.  The Stealthburner part cooling fan is set to run in a range between 50 and 70% during regular printing as determined by the slicer (Orca), with 100% reserved for bridging.  The default is to run the part cooling at 100% all of the time.

...

Max speed for solid infill is 200mms.  Outer walls 120, top surfaces 100.

There's a couple of points that I would look at more. PLA loves cooling, run your fans 100% all the time for PLA. Also, your speeds are likely high (I was going to ask about that). I'd try running higher cooling fan speeds then slow things down. I'm running 80 for outer and 120 for inner walls and 110 for solid infill on my plain brass Revo nozzle.