break lines in print (Sidewinder X1)

[Puffstar 0]

Hi Guys,

Hope you can help. Printing a Storm Trooper helmet from Thingiverse and noticed Im getting break / support lines in the fill.These lines are also occurring on the support towers so I know its not in the design. I cannot see them in the slicer preview at all.

 

Using Cura 4.8.0

Artillery Sidewinder X1 profile

Add support touching built plate

20% infill

0.2 layers using 0.4 nozzle 

 

Any help would be greatly appreciated.

 

.

 

 

Edited January 10, 2021 by Puffstar

[GregValiant 1,488]

Zooming in it looks like it may be intermittent under-extrusion.  You might be getting a partial clog in the nozzle and then it clears itself.  It's hard to tell but is the very top layer rough on the outside edge (looks like there are little points all around)?

Have you heard the extruder missing steps?

 

[Puffstar 0]

Thanks @GregValiant for the reply. If it was a clog it would not be so uniformed perfectly to that layer. It appears to be a fill issue where it looks like its inserting a break / join line.

 

Will research "extruder missing" as I am not familiar with that.

 

Cheers. 

[GregValiant 1,488]

"I cannot see them in the slicer preview at all."

That's because they aren't there.  Consider that Cura would have to decide (all by itself) to add a feature, and to do it randomly, after generating the preview which is from the gcode it generates.  That doesn't happen.  Your lowest problem line appears to be more than one layer tall.  Those things that look like dots around the top rim are also present in the upper line where you have the arrow.  That's a sign of under-extrusion.  You notice that when the extrusion flow is correct that the outside wall is nice and smooth.  No dots.  If you run your finger along that top edge I think you will feel the dots.  It should be smooth.  There is no setting in Cura to change the flow for "A Layer".  You would need to specify the layer and the flow for that layer.  It can be done, but you would need to use the Change at Z plugin, or hand code some M221 lines into the Gcode.

 

When there is a clog - the extruder motor struggles to push the filament through.  If pushing requires more torque than the motor can deliver, it will "skip steps" and snap backwards.  It is an indicator that something isn't right.  It is a noise that anyone with a printer will hear from time to time...and learn to really hate.

 

White filament can be very difficult to dial in.  It contains the most colorant and I think they use titanium oxide as the colorant (very white and used in paints).  I print most PLA at 210, but white at 200.