Cura 3.2.1 Underextrusion after retraction

[jofleck 0]

Hey folks, 

I own an ultimaker 2 for a while. Usually Im using simplify3D + Octoprint for slicing. Now I gave Cura 3.2.1 a try because I really like the octoprint integration and the tree supports are absolutely awesome. However I have problems when Im printing objects which needs a lot of retractions. I am experiencing underextrusions every few layers so I can break the model really easy. Currently I'm printing at 0.1mm layer height with 40mm/s and 20mm/s inner and outer wall speed. I'm retracting 4mm at 25mm/s (Same settings as in simplify3D). 

 

I played around with speeds, other filaments (I'm printing PLA) and temperatures. Nothing helped except slicing the model with simplify3D. 

 

Do you have any Ideas? 

 

 

Edited March 15, 2018 by jofleck

[Brulti 177]

Hello,

 

Could you post your model here? That way we could give it a try ourselves and see if we can find what the problem is.

[jofleck 0]

Hey folks, 

I resolved the problem. Maybe someone has the same problem. So here is the solution:

 

I installed Cura on another Computer and tried it. On this machine everything worked fined with the default settings. So I enabled all settings and compared them with the settings on my primary computer. I noticed that the initial layer temperature  was always 20°C hotter than the normal temperature (This setting was hidden). In my Case 230°C for the initial layer was to hot. When the printer began to retract about 20 (!!!) layers later, suddenly liquid filament dropped out and after this I had underextrusion the next few layers. 

 

I have no explanation why the initial layer temp was alway 20°C more. I reinstalled Cura and deleted all corresponding files. Now its working like a charm

 

But really, really interesting that a to hot temperature can affect the print even 20 layers later....