Welcome to the SeeMeCNC Community

I've recently printed this part, and it seems to be some filament starvation, but it's like a pattern.
Could it be the roll of filament and in consecuence the input used? I've meassured it, and it goes from 1.79 to 1.74 :S
or it might be something else?

E-steps are calibrated, belts seem tight enough, effector with spring clips and acetal u-joints, so there is almost no play


Full size picture: https://farm1.staticflickr.com/388/1928 ... 9695_o.jpg
[img]https://farm1.staticflickr.com/388/1928 ... 9695_o.jpg[/img]

[img]https://farm4.staticflickr.com/3893/190 ... 41d5_o.jpg[/img]

The pattern is the cross-hatched pattern in the second layer, visible through the gaps in the under-extruded section of the first layer.

What material is this and what hot end temperature are you running? Do you have the PEEK fan and shroud installed yet and are you sure it's running consistently during the print? Did you happen to watch what the hot-end temperature was doing while this was happening? If you take the hot end up to temperature and manually turn the extruder drive, how much resistance to extrusion is there?

IMBoring25 wrote:The pattern is the cross-hatched pattern in the second layer, visible through the gaps in the under-extruded section of the first layer.

Indeed, the pattern repeats itself to the other layers of this print.

IMBoring25 wrote:What material is this and what hot end temperature are you running? Do you have the PEEK fan and shroud installed yet and are you sure it's running consistently during the print? Did you happen to watch what the hot-end temperature was doing while this was happening?

ABS black, 240ºc, (2.8mm retracts 40mm/s speed)
I'm running an E3D V5 with the fan. Yes, the fan turns ON with the hotend (connected to HEAT1).
The temperatured was consistant during that part.

IMBoring25 wrote:If you take the hot end up to temperature and manually turn the extruder drive, how much resistance to extrusion is there?

I'm not at home right now. Will check that as soon as I can.

Thanks for your help.



I will try with different prints, same material, and see if the thin lines are in the same location.
More temperature, 245ºc maybe.
With 1.75 filament diameter instead of 1.76 but no hopes with that.

Yeah I'd try printing the exact same part in the exact same location again and see if you get the same problem in a different area.

It sure seems like it's due to the variation of the filament diameter. If that's the case the only fix is to use filament with a tighter tolerance.

Just to be sure, I removed the nozzle, torched it, clean everything and reinstalled it.


Printed 3 of them, 5ºc higher. the first one is in the exact same location.
The pattern changed, and layers are with some offset. Tower allignment? belts too tight?

https://farm4.staticflickr.com/3807/191 ... 8b1a_o.jpg
[img]https://farm4.staticflickr.com/3807/191 ... 8b1a_o.jpg[/img]
To be honest, it doesn't look that bad in person. It looks terrible by watching the picture

https://farm1.staticflickr.com/325/1928 ... eb39_o.jpg
[img]https://farm1.staticflickr.com/325/1928 ... eb39_o.jpg[/img]

Are the areas of underextrusion immediately after a travel move? What retraction length and speed are you using?

E3D V5 / 2.8mm retracts / 40mm/s speed

Yes, after a travel move, but doesn't seems to be after a retract.


Just wondering if this could cause other problems:
[img]https://farm1.staticflickr.com/300/1869 ... d09e_c.jpg[/img]
Last week the heat break broke... don't ask how So a lathe operator (? can't find the word in english) made me one.
The problem is that the machined part between the heater block and the heat sink is bigger than the original.

Instead of 2.8mm diameter is 4.7mm

So I decided to give Slic3r a chance, downloaded the last stable version (1.2.9) and god... I love it.
Now they support filament overlap and the new beehive 3d infill seems great.

The filament starvation pattern disappeared and layer alignment got so much better.
Im a picture guy, so here they are:

(man... it's so hard to take pictures of black abs )

Original CuraEngine print:
https://farm4.staticflickr.com/3756/191 ... 1d5d_o.jpg
[img]https://farm4.staticflickr.com/3756/191 ... 1d5d_o.jpg[/img]

Same settings Slic3r print (unfinished print):
https://farm4.staticflickr.com/3913/187 ... 9041_o.jpg
[img]https://farm4.staticflickr.com/3913/187 ... 9041_o.jpg[/img]


Both, here you can clearly see the layer alignment:
https://farm1.staticflickr.com/447/1915 ... 40ee_o.jpg
[img]https://farm1.staticflickr.com/447/1915 ... 40ee_o.jpg[/img]


Thank you all for your help.
Martin.

Do you think slic3r is just slowing things down so you get a better print? or was the speed setting the same?

Yes sir, both with the same speed.
Same settings in general. Infill is different.

Also, I've printed that part like 6 times with Cura trying different speeds, flow, etc with no luck.