How do I get a consistently flat printed first layer?

Snapmaker 2.0
1

Hi,
I’d like to get some advice on how to get consistency on the first layer surface when printing PLA.
I’ve only been using the default Luban settings for PLA, and generally been getting OK results, but lately is not behaving. I have no issue with ‘Bed adhesion’ or ‘layer adhesion’ I’m really just concerned about the aesthetics of the flat surface when part is removed from the bed (ie: Ideally would like the visible part to look nice and smooth without and lines or dips… which most of the time I was able to get) But lately I struggled to get the nice flat surface and I’ve attached some pics to show the mixed results. Is there any specific settings or tips to help ensure this time after time or it is just trial and error artform? Is it purely related to z-axis tolerance? OR something to do with the first layer line thickness (default is 150%)? OR Bed temperature? Any thoughts appreciated. Cheers, T

_20220222_200923
_20220222_2009232303×2039 449 KB

_20220222_201117
_20220222_2011171920×1587 171 KB

_20220222_201517
_20220222_2015171920×1280 147 KB

_20220222_200903
_20220222_2009032394×1890 447 KB

_20220222_200837
_20220222_2008371575×1585 326 KB

2

I resolved with a glue stick

3

My first two guesses would be that the nozzle is slightly too far off the bed or you’re underextruding. Try dialing back to 100% line thickness for starters, even if that seems counterintuitive, and see if that gives better results (the older version of Luban that I have open right now defaults to 100%, and I seem to recall someone else having problems with corners and edges at >100%). Calibrate esteps if you haven’t done so yet.

1 Like
4

Most of your prints are to far off the bed, try a hot calibration with 60°C bed (or what esle you print with). I would suggest to preheat the bed for 30min or so, to let the material and machine expand.

First layer quality also depends on layer height which compensates the tolerances of the buildplate a bit. 0.2mm is a good start.

I would suggest to calibrate your extruder (e-steps) to be sure you have no underextrusion. Search in the forum, there are a lot of threads about.

1 Like
5

Hi, nice one thanks for your reply I’ll try as you suggest. Tbh I do always calibration cold, so did wonder what happens to the hard, set bit of PLA still left in nozzle when adjusting z-axis. Didn’t realise can do hot calibration. Cheers