First layer or feeder issue?

[vincentbaas 19]

I'm having a strange issue with my UMO+, that I haven't been able to figure out myself. My last succesful print was a pretty large 5h print, but after that the problems started. It prints a very uneven first layer, it almost looks like too much material is deposited. This causes the nozzle to start 'plowing' through the material, and causes it to push down the print bed. At first I thought it was a feeder issue, as the knurled bolt was grinding into the filament. But now I think the issue must be somewhere else, as the feeder seems to be working fine. 

 

I feel I've tried all the options I could think of myself, so I need your help here. Am I having a first layer or a feeder issue? Or is it something else? 

 

Things I've tried already:

• Cleaning the nozzle (atomic), knurled wheel, and bowden tube multiple times
• Replacing the little black feeder wheel with a steel bearing
• Changing material (both ColorFabb PLA/PHA and Ultimaker PLA)
• Checked if belts, pulleys and other screws were still tightened
• Leveled the print bed multiple times, both closer and further away from the nozzle
• Checked the PTFE coupler, it still looks fine
• Checked and tightened the screws in my pulleys, short belts, print head. None of theme were loose. 

 

Pictures:

Test cubes: 0.3 mm first layer at 205C, bed at 50C. Left 100% flow, right 80% flow.

 

Bed leveling test: 205C, bed at 60C. The print itself is even, only the material 'plowing' remains. 

 

 

Edited January 21, 2018 by vincentbaas