I have spent parts of the last 2 days trying to finish calibrating a hardened stainless steel .60mm nozzle with Sunlu PLA+ 2.0 filament.

I have been trying to print a test cube and I couldn't get the first layer to stick period. I washed plates, I swapped plates, I removed the nozzle and reinstalled it.

I swapped different filament brands, and they all printed flawlessly. Try that Sunlu white PLA and instant failure again. I was about ready to admit defeat and dry my first spool of PLA ever because I could think of nothing else to do.

But I took one last look at my settings for this filament. And I finally noticed my flow ratio was set at .096 rather than .96. I didn't even know the slicer would allow a number that small.

Once again the error was found to be located between the chair and the screen.........

I once spent quite a bit of time because I fat fingered a huge retraction amount and failed to spot it for days. You wouldn't think the slicer would have allowed a 50mm retraction distance either. It was a direct drive extruder and I was unloading my filament when I thought my extruder was stopping up randomly.

Thanks for sharing. It feels good to know you are not alone. I had a similar experience once where after lots of debugging I realized the "PLA" I was using was in fact PETG and I was extruding way too cold.

Ha! Years ago, I once spent nearly 2 whole days trying to unknowingly splice PLA and PETG together. All because I was an idiot and didn't read the spool labels. I just assumed, with the obvious results and damage to my ego....

Isn't amazing what slicers can do? There ain't no guard rails where we're going!

I sort of did this today. I was testing what each setting in orca slicer's scarf seam section did and I had the scarf flow at 0.6 and forgot I even had scarf seam on but some seemingly random features ended up as disconnected lines and I blew through like half a roll in calibration prints that came out flawless or near flawless before I realized

Try setting the scarf steps to 1 and the Bridge Flow ratio to 1.5, (as low a 0 and as high as 2). Then under Speed uncheck the Slow Down for Overhangs and set the speed to 20mm/sec. This is often a good place to start and works well on my Bambu mini. For testing, I print an upside down box with a 50x50 cavity and a height of 8mm.