Troubleshooting printing layer squashing? I am having a strange intermittent printing error specific to one particular object I'm trying to print.



My printer is a BCN3D Sigma R17. I am printing a thin wall (0.6mm) cup object. I'm using:


Simplify3D with Sigma Progen profiles
0.6mm brass nozzle (w/thermal paste)
0.1mm layer height
Spiral (vase mode)
Filaform PLA.


As you can see in the images, the first few layers print ok, but then the nozzle seems to collide/penetrate the previous layer and grinds against it as it moves around in a circle. The result is a combination of rough textured surface and good quality surface. One half of the print also seems to be thicker, presumably from the increased extrusion width caused by squashing layers in the z-axis. I’ve tried


changing model's wall thickness,
disabling spiral mode
increasing layer height
changing filament
upgrading printer (latest stepper drivers)
changing extrusion width
performing full calibration


All without success. You can view the gcode and S3D fff profile here:
https://drive.google.com/drive/folders/0B6SnaYyiYI7vcGU1U3Uxb0RrX3M?usp=sharing

The image shows some filament left hanging from a stopped print. It seemed to be squeezed out from excess pressure, as if it was being blocked during the print due to being pushed against the layers.
Well, for a 0.6 wall thickness using a 0.6 nozzle you should have one line for the whole wall. But I´m seeing in your prints walls of 0.1 and 0.4 as infill, Why?
I´m using simplify3D and I can see the results about walls and infill prior to send to the printer. On this kind of parts avoid infill and give priority to walls.

So the main problem with your gcode is that wall thickness, is too much difference between the filament extrusion 0.6 vs 0.1 this is 16.6% of the printing flow, so you need to set print flow to 16.6% or 20%, not 80%. 
You must need to use retraction to avoid blobs and set a lower temperature.

I saw this video to control Coast issues, but is explained how to set settings on Simplify3D; I hope you can visualize your issues before printing.
https://www.youtube.com/watch?v=WWpdGY0V-gM