Smudgy/ripply top layers & solid infill
Any ideas where these smudgy top layers come from? Especially the corners?
It's a VC3.1 400, enclosed, Rapido UHF fed by Orbiter. PLA, printed after excessive heatsoak, 0.6n, 0.4lh
I did: tune PA, checked my rotation distance, calibrated flow, reduced extrusion width on top layers and top solid infill to 0.41, reduced infill/parameter overlap to 5%. Sliced with PrusaSlicer 2.8.0
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12 Replies
can you try without top and front panel so that the champer is vented for PLA?
I have my front open and have a separate temperature sensor and fan for the chamber. It maintains 25°. Should be fine...
I printed the same gcode without PA - looks the same.
What's your print speed and your extruder temp
I faced similar problems the past days.
One of my finding is that my T0 is hotter than displayed which caused ripples on my top layers while printing at 210 C because it was actually at 230-240C.
After reducing it to 190C I gor better
This way my primary source for the ripples
The 2nd problem afterwards were gaps + ripples. This was caused by an to high print speed (Default profile in PS is not suited for PLA @ 200mm/s lol)
Reduces it for testing to 100mm/s max and got a perfect top layer
@boinappi have you made progress?
Not really:
I followed https://ellis3dp.com/Print-Tuning-Guide/articles/first_layer_squish.html and realized that the first layer squish has quite an impact to top surface layer quality, even if the top layer is in a higher layer with sparse infill below, which allows the filament to relax. I also learned that the stock print bed is quite tolerant to first layer squish.
In the pictures i posted i printed with 3 top layers. The finishing, smudgy layer is printing significantly slower. The layer before has a lot smoother surface than the final layer, which could be a sign that i don‘t fight with thermal x-gantry issues, but i can‘t prove it yet.
I also need a more structured approach to this issue - there are yet too many variables. I implemented a heat soak script (did it manually before) and (can someone confirm this could be an issue?) do my tests with a stable room temperature.
Btw.: happy new year and trouble free 3d printing 😉
Okay - finally some new insights:
I am now at a stage where i can rule out two major culprits of my prior prints:
1) warping
2) thermal x-gantry issues
Both got better with a heatsoaking script. I did heatsoaking before, but i guess my manual approach was not good enough.
Additionally i calibrated first layer squish, which has major effects on top surfaces.
v0: This is not perfect yet - but already way better than before. You can spot some fins along the edges and - which i think is much more of an issue: one corner with more material (nearly a blob).
Questions: Why this corner? Is this PA related?
Print info: 0.6n, 0.3lh, 10% infill, 4 top layers, 40x40x10
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This could be related. Unfortunately they didn‘t find a solution. https://forum.prusa3d.com/forum/original-prusa-i3-mk3s-mk3-how-do-i-print-this-printing-help/blobbing-at-corners-of-print-only-on-one-side-help/
Original Prusa 3D Printers
Blobbing at corners of print only on one side, help!
I work with pixel art and will be doing a lot of tight-cornering prints, and I’m having a bit of a surface issue. This only occurs during the infill ...
v1: Reduced top layer speeds and solid infill speeds to 1/4 of the print speed of the last version. Not really a great difference. Will focus on PA now.
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Hello do you get any succes ?
Hello do you get any solution for this ?
Yes. There were many, each of them with a little success and over all I get quite nice surfaces now.
1. heat soaking your chamber
2. check your heat soak - I did the paper test
3. calibrate your first layer
4. calibrate first layer squish
5. calibrate extrusion rate
6. calibrate PA
Check Ellis Print Tuning Guide for details. There is also an issue with small top surfaces and overextension principally.
I also switched to Orca Slicer for calibration.
I thought first layer calibration and first layer squish is the same 🤔
Do you have a photo of your results now