Issues when printing first layer of 0.3mm or more with PLA
Good afternoon,
I recently finished the assemble of my new Prusa i3 MK3S kit and i am doing my first printing with it, but there is an issue with the first layer that I do not understand.
I have done a few prints using a layer height of 0.2mm and 0.25mm and the first layer prints fine, however as I noticed the Prusa Slicer suggest to prints the first layer with a different height (larger) than the other layers I tried with 0.3mm and the problem started.
I do not know exactly hoe to describe the problem so I am attaching a couple of pictures of what happens.
I tried to adjust Z live and it sort of worked but not properly.
Would appreciate any guidance on the subject.
Regards,
Julian
RE: Issues when printing first layer of 0.3mm or more with PLA
Having troubles attaching the photos. Do they need to be of any specific size?
RE: Issues when printing first layer of 0.3mm or more with PLA
RE: Issues when printing first layer of 0.3mm or more with PLA
It looks like a bed contamination issue. I don't recognize the material: is the bed PEI or some other material? Or is it a cutting board? Dooh 🙄
RE: Issues when printing first layer of 0.3mm or more with PLA
Also keep in mind: Most profiles use a 0.2mm 1st layer height. This is thick enough to account for minor bed inconsistencies, but not so thick as to create problems with adhesion and cooling. If you are using a 0.4mm nozzle, the absolute maximum recommended height is 0.32mm (80% of the nozzle size). At this size, extrusions have a round cross section as layer height approaches extrusion width. There is less "squish" with the underlying bed layer which leads to poor adhesion, which may account for your issue. I stick with a 0.2mm layer height regardless of other layer heights even when printing thick layers with a 0.8mm nozzle.
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RE: Issues when printing first layer of 0.3mm or more with PLA
@tim-m30
Hahaha sorry Tim, yes that is a cutting Board, the printer has a pei smooth bed but regarding your comment I would like to clarify that I used isopropyl alcohol before the printing
Thanks
RE: Issues when printing first layer of 0.3mm or more with PLA
@bobstro
Thank you, will bear it in mind. However the printing I was doing was at 0,3 which according to your theory should be fine, therefore I would like to have more thoughts on the subject to understand what is happening. I was using a Snapmaker Original, before having my new Prusa, and never had anything like this printing at 0,3mm layers.
RE: Issues when printing first layer of 0.3mm or more with PLA
Alcohol will cause that sort of contamination. Unless you are fastidious and use a virgin rag and ounces of alcohol, it is very easy to leave an oil film residue on the PEI. You can check for a film by simply running a fresh paper towel dampened in alcohol or acetone across the "clean" sheet. Any streaking, refraction or sheen during evaporation is caused by oils on the bed. I have found it nearly impossible to get a clean sheet using alcohol. Soap and hot water works every time (except when I accidentally grab my disk sponge to scrub).
RE: Issues when printing first layer of 0.3mm or more with PLA
@tim-m30
Thank you Tim, will look at it.
Precisely today I was doing a large printing and the first layer was working very well for most of the area but there was a region were I was seeing waves and not good adhesion on the layer, maybe it was some oil in that specific place.
Regards,
JES