External perimeter separation on eastern side  

New Member

I could use some help debugging what's going on with this artifact. 

For my first 3D printer, out of the box, the MINI printed smoothly with the default equipment and settings and Prusament! So I started to experiment with new equipment and different filament.

I purchased some MH Build series PLA filament, as well as a hardened steel 0.6mm nozzle, but the experience was not as smooth. 

Some prints went smooth with those new variables, but the one thing I'm trying to trace down right now is this separation between the object and the external perimeter. Oddly, this only happens to the perimeters on the east facing side (the one closest to the z-axis gears, or x position in the direction of 180). The print settings are kept to the default for the most part .. 0.2mm layer height, 3 perimeters, temps of 215 first layer and 210 other layers, using the default "Original Prusa MINI 0.6 nozzle"

On the first layer, this separation is not present and presents a solid connection between all perimeters and infill. But as this image represents, when I have a flat surface on top, you can see a slight separation on this one eastern side. (Ignore the stringing, that's another challenge I'm iterating through).

Any thoughts on what could be causing this separation on the eastern side of my prints? Or are there some settings I should be tweaking in the PrusaSlicer?

Posted : 15/09/2020 3:23 pm
Noble Member

I do not use the Mini, but this looks like a simple case of a slight underextrusion.

If this were my print, I would probably try increasing the extrusion multiplier in the slicer very slightly.

Posted : 15/09/2020 4:03 pm
Trusted Member

Hardened steel nozzles don't have the same thermal properties as brass nozzles, you'll need to raise your hotend temps up by maybe as much as 10 or 15C to mimic results from a brass nozzle. Also as mentioned above tune in your extrusion multiplier. 


Posted : 16/09/2020 3:46 am
New Member

Thanks for the suggestions!

I started a grid search on the extrusion multiplier setting with the temp increased, and could use some help interpreting the results.

I can clearly see visible gaps between layer lines at 1.0 and 1.015. But also at 1.015 I can see some excess material near the perimeters, which continues on through 1.075. Or am I interpreting the imperfections at the corners incorrectly as over-excursion when they could just be blobs (which is contributing to the stringing)?

For stringing, my understanding is I focus on a grid search through the Retraction Settings next. Before heading down that route, it'd be helpful for my learning if someone with more experience than me could chime in at to which extrusion multiplier they'd continue with from the image above.

Posted : 16/09/2020 3:51 pm

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