Unpredictable Print Quality

I have been printing mostly PLA and PETG with fairly good results. I recently printed a very large box. I got lots of strange results (see below). I did a flo calibraion some time ago and was wondering if these are the result of the wrong K value. Is there an easy way to rest to factory K values? Do you have any other idea as to what is going on here. This was printed with Voxel PLA Plus.

Print Project File:

Thanks… Richard

I’ve noticed a few patches like this myself.
My thinking is that given the temps are all stable, the flow is calibrated and the other parameters are fixed (retraction etc) something is changing.
The only things that spring to mind would be filament diameter or composition, a small change in either would be noticable and probably more noticable when you’re printing fast which is the default with these printers.
So retraction is possible, slightly less than your current value perhaps.

I’ve also tried some PLA filament that is touted for high speed printing, it has a slightly lower viscosity at print temperatures I think, TBH it didn’t look like a quantum leap in anything but there were less defects which might say it is better or that the prints weren’t the shapes that trigger defects like this.
Instead of sharp angular corners I’ve been putting a tiny fillet on them so I don’t get a stop and retract anywhere near the corners and edges, seem to work as well.

Thanks. I ran a calibration cycle on the printer and printed two small parts with two different rolls of Voxel PLA and they printed great.

Tomorrow I am going to print a slightly bigger part with the original PLA that had the issues. Curios to see what happens.