Help on fixing missing z layers

[Ridgerunner2270 0]

Hi all,

 

I'm new to 3d printing. So, this maybe a common problem to fix (I just can't seem to find a fix for it).

Anyways, the problem I'm having is missing Z layers when printing a model. You can see this problem in the attached image. What I really don't understand is the problem doesn't show up in Cura's layers view. Any idea what could be wrong? This happens with other models I've tried to print out as well.

 

Thank you for any help!

 

 

[Labern 774]

If layer view looks ok then you probably have under extrusion or a problem with your z-axis.

If its the same height in every print then it will be Z-Axis. but if you get it randomly then is probably under extrusion.

A closer look at the missing layers would help determine your issue and sharing what printer you have and material used, settings like nozzle size, speed, temp and layer height will also help.

 

[Ridgerunner2270 0]

Hi Labern,

 

Thanks for replaying. The printer I'm using is a Creality CR-10 mini. The material used is PLA+. Nozzle size is 0.4mm, speed set to 40mm/s, temp to 230C (Seems to print better at that temp. smoother result), layer height was set to 0.08mm. A closer look at the layers is attached and every setting in Cura also. Like I said, I'm still very new to 3d printing. So, there's probably a lot of setting set wrong lol. 

 

Also, I've noticed that as I scale the models size in Cura, the position of the missing z layers seems to move, but I'll have to double check that by printing a couple models. 

 

Hope this helps!

Edited March 7, 2019 by Ridgerunner2270

[burtoogle 513]

Hello @Ridgerunner2270, please could you attach the gcode for one of the prints that has missing lines.

[Ridgerunner2270 0]

Code for the Groot model and a Deadpool I just printed that seems to have the same issue (See image). 

CCR10_deadpool-bust.gcode CCR10_Groot_v1_1M_Merged 120mm.gcode

[burtoogle 513]

Hi @Ridgerunner2270, thanks for the gcode. As you can see from the attached images showing that gcode. There are no lines/layers missing. So it is more likely to be a problem with your printer that is somehow triggered. Perhaps there is a setting that can be adjusted?

 

 

[Ridgerunner2270 0]

Thank you for the idea. However, I have zero to no idea what setting on the printer would cause it you skip like that, but I'll try to see what I can find online when I get home later. Anyone else have an idea?

[Labern 774]

Don't know much about your printer. But you may need to check to see if the filament is grinding or slipping in the feeder. or if you hear knocking sounds coming from your feeder.

[Ridgerunner2270 0]

Actually, I do hear a sound every once in a while from the spool (Feeder?), when I'm printing. I thought that was normal? If it's not normal, what do I need to do to fix it?

 

Nevermind. I know what your talking about now. I haven't heard any popping coming from the feeder, but I'll make sure the teeth on the gear is clean when I get home.

Edited March 7, 2019 by Ridgerunner2270

[Labern 774]

This is an Ultimaker forum so you may not get your answer here. But check your nozzle is clean. Maybe carry out an atomic pull. Check filament passes through the bowden tube and nozzle properly. You can heat the nozzle, open the feeder and push filament through by hand and it should push through without too much force. 

other then that have a look for a CR10 forum which may offer better advice. 

[Ridgerunner2270 0]

Okay cool. I'll see if I can find a creality CR-10 forum to get more help on the problem. Thank you to everyone that tried to help.

[Labern 774]

If you are hearing a sound coming from the spool then the filament could be catching and this can also cause under extrusion.

[dirrunner 0]

Hi All.

Looks like I catch same issue.

I sliced (Cura 4.8.0) test cube and notice missed layer, then I printed another two copies from same g-code file and catch same missed layers on same height. Next I sliced test cube using another slicer software. And models are perfect. 

I start to check G-Code and found out:

I think it's software issue. Extra 0.3 mm per layer. It's a reason of horizontal gap. But I have no idea about root cause.

[gr5 2,172]

@dirrunner please post your project file: go to menu "file" "save...".  The resulting file contains not only your STL but the scaling, positioning.  Also it has your machine (printer) settings, your material settings, your profile used, and settings that you overrode.  Please post that here.

[dirrunner 0]

@gr5 hello

Here is my project file.

Test_Cube.3mf

My previous guess about extra 0.3mm was wrong. I didn't notice next lines returning print nozzle after Z-Hopped retract:
G1 F3000 E1066.37277
G1 F120 Z10.7
;MESH:NONMESH
G0 F3600 X126.244 Y118.89 Z10.7
G0 X112.504 Y112.184
;TIME_ELAPSED:808.275368
;LAYER:51
;MESH:Test_Cube.stl
G0 X112.504 Y112.184 Z10.9
;TYPE:WALL-INNER
G1 F120 Z10.4

I made one more slice of TestCube with Cura and print it. And gap at the 50 layer is still here. You can see it at the attached photo.

[gr5 2,172]

I opened your project, sliced it, looked at the gcode.  I think it's pretty obvious what the problem is.

 

Notice how Z is always increasing up until the layer that fails.  Searching for "Z" only here is a few lines before and after the failure:

G0 F120 X118.73 Y116.594 Z9
G0 F120 X124.952 Y117.032 Z9.2
G0 F120 X118.857 Y125.518 Z9.4
G0 F120 X109.074 Y114.165 Z9.6
G0 F120 X117.745 Y116.448 Z9.8
G0 F120 X125.854 Y109.449 Z10
G0 F120 X109.075 Y110.976 Z10.2
G1 F120 Z10.7
G0 F3600 X126.244 Y118.89 Z10.7
G0 X112.504 Y112.184 Z10.9
G1 F120 Z10.4
G1 F120 Z10.9
G0 F3600 X126.186 Y118.755 Z10.9
G0 X112.682 Y112.242 Z11.1
G1 F120 Z10.6
G1 F120 Z11.1
G0 F3600 X121.379 Y114.229 Z11.1
G0 X112.686 Y112.245 Z11.3
G1 F120 Z10.8
G1 F120 Z11.3
G0 F3600 X122.903 Y110.625 Z11.3

See the change at layer 10.4?  Until then Z is always moving up before printing the layer.  Starting layer 10.4 it is always coming *down*.  You have play in your printer.  In the Z axis.  This is normal.  This is why you should never use zhop.  The only printers that can use Z hop without problems like this are delta printers.  Google "delta 3d printer".  Those printers move all 3 axes all the time so they are build to have zero play/backlash.

 

So turn off zhop and print it agin.