Problem with second third fourth layer...

[metejnik 0]

Can anyone give me some guidance as to why the first layer is ok and the next ones are bad?

The first layer is perfectly smooth, but the next ones are visible in the photos, which are disgusting and even the nozzle rubs on them as it moves.

Ender 3 v2, Mriscoc firmware with Manual Mesh set up, double Z axis calibrated, dual gear extruder set up, 0,4mm nozzle, quality 0,2mm, filament PLA, UltiMaker Cura 5.5.0, print speed 50mm/s, retraction distance 6,5mm, retraction speed 35mm/s.

Thanks in advance!

Edited November 18, 2023 by metejnik

[Slashee_the_Cow 272]

The first layer usually prints with different settings - often taller and wider, with higher flow.

 

With transparent materials, you generally want to use the thickest layers and widest lines possible, since the most visible parts are the seams where two parts meet.

 

If your parts don't need to be strong, you can change Top / Bottom > Top/Bottom Line Directions to a (single) number like 0, 90, or 45 depending on the orientation of your print. Look in the preview, you want the angle which will give you the longest lines. Just please note that as I said, this will compromise strength because it's basically only reinforcing one direction instead of two (0,90) or four (45, 135).

 

If the retraction settings you mentioned are the ones you generally use for any PLA, it's worth testing this filament specifically. Things like this, or "silk", can be more flexible, stretchy, or just plain harder to grab as normal PLA.

 

If the nozzle is rubbing against higher layers, it sounds like your filament is expanding as it dries. You'll probably have to make all settings visible for this one, but see if you can go to Material > Vertical Scaling Shrinkage Compensation and test turning it down a tiny bit (like 0.1% at a time, or more if that makes barely any difference - it's not something I've ever had to play with).

 

Finally, I might not understand all the laws of optics (the circle of confusion just confuses me) but it's a fact of life that unless your material is 100% transparent - and this isn't - every time you add more, the whole thing becomes more opaque. You're never going to get a really transparent result from FDM printing. About the best you can do is want to have something thin and not detailed, break out a 1mm nozzle, hope your hot end goes hot enough and lay down the thickest single layer you can.