Silk PLA curved surface imperfections
I'm having this recurring issue with Esun Silk PLA and sometimes any normal PLA on a curved surface. It almost looks like Z seam zits but it is completely random on where it happens as I have the Z seam located on a sharp edge. This happens at layer heights of 0.10, 0.15, 0.20 all on quality setting in Prusaslicer.
Things that I've tried to fix this issue:
- Different nozzle temps from 190-220
- Slowing the printer speed
- Increased/decreased retraction speeds & distances
- Increasing flow in Tune (i3Mk3s+)
- Increased/Decreased extrusion multiplier
- Wipe while retract enabled
- Retract on layer change enabled
- Only retract when crossing perimeters enabled
- Reduced fan speeds to 50% ( fan enabled after the first 4 layers)
I've now run out of ideas as to where to next try. I see someone else on this forum had the same issues I have but there wasn't a solution posted
you can try to align the seam position using aligned, or rear, or paint where you want it to be (requires PS 2.3)
(not sure to understand your "I have the Z seam located on a sharp edge" to me it seems to be the seam position)
The Z seam was set to the far right of that image as its a turbine blade so the seam is on a edge/corner of the print. In the Z seam settings it is set to Aligned
I had a similar issue with silk PLAs on my mini. The polymer blend used in silks to make them shiny, makes them a bit thicker. I found the best results for surface finish and what looked like underextrusion was to decrease retraction length AND speed. Printing them at 215-220 with just enough retraction to stop flow, and slow enough that it doesn't separate the melted blob from the unmelted filament so it actually pulls back, gives me a good surface finish and minimal if any stringing. Also you can reduce retract % before wipe.
As it's a turbine blade I assume you'll be post processing to smooth out the printed texture and reduce surface turbulence so a quick wipe over with a fine abrasive paper to denib the surface beforehand should be OK in this case.
In many cases minor surface imperfection are simplest to deal with if you give the part what you can think of as a quick, final, polish.