Bands in Z axis, over extrusion...bit of layer shifting

#1
Hi All!!

I'm a newish owner of the Gmax Pro 2 Dual Extruder Chimera. This thing is built like a tank, but I sure am having a bunch of difficulty getting it dialed in. I have a farm of medium sized Sovol SV01s that are rather simple to dial in. This was my first step into a mega build volume and I hoped it would allow me to do some large custom jobs people have been asking for. Please bear with me as this may get long, but I want to be detailed so you don't have to ask to many questions.

Issue: I'm getting bands or over extrusion on the outer perimeters and seeing some layer shifting. See attached Benchy pics

What I've Done:
- PID tuned
- E-step calibration
- Flow calibration (Single wall print and measure wall thickness and adjusted my flow so the wall thickness matches my nozzle width)
- Tightened belts (Oh they're good now) - Gcreate - Please add simple belt tensioners :)
- Temperature Tuning for my filament (3Dfuel PLA Pro)
- Bed leveled, Z- offset good, first layer looks great
- Reduced Jerk settings to 3 mm/s
- Reduced Acceleration to 300 mm/s
- Print Speed 40 mm/s Outer Wall Speed: 20 mm/s Inner Wall Speed 14 mm/s, Travel Speed 100 mm/s
- Retraction speed 40 mm/s, retraction distance .75 mm
- Deleted filament runout sensor to reduce any drag so filament has a straight shot to the extruder
- Bed power cable addressed so it doesnt snag on the extrusion
- Print head doesn't have any play and is firmly attached to the rail

I am your student. Please teach me :) I'm open to any advice
 

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