I'm a bit stumped, and am looking for advice. I have an extremely old (Circa 2015) Craftbot Plus. It's hardly any parts of the original unit, kept alive with custom parts out of just spite. I use cura as my slicer, and it works fine for my needs. Recently, my kids have wanted to print custom keycaps. This is a difficult FDM print to begin with, and my old hardware isn't doing me any favors; it might be impossible. That being said, my prints turn out good, except for the tiny details in the actual stem. The picture is attached of various settings; I've tried a ton of stuff. I can share a cura profile, but the gist is I'm printing in PLA and have experimented with 195-210 degrees, .1mm layer height, line widths between .175-.2mm, various speeds, minimum speed and minimum layer duration, I've disabled ironing, and I've played with retraction. I'm kind of stumped, and am wondering if anyone has things I should try.
Have you adjusted your flow rate? Slicers are usually pretty close to spot on for 0.4mm nozzles but in my experience going up or down in nozzle size usually results in having to change the flow % pretty significantly. In addition to what others have said about minimum layer time / heating the parts up too much, I think you may be over-extruding as well.
The test I like for testing flow is to print a handful of cubes ~15 layers tall, with 2 bottom layers, 3 infill layers, and 10 top layers. Print each one at a different flow rate (in cura you can change settings per part to print them all at once) and look at the top layer when it's done. You don't want any bulging from between print lines (over-extruding) or any gaps in between them (under-extruding).
Yea, I've adjusted it down a bunch, but I think I bottomed out at 90%; do you think I should go lower?
Print a calibration test. Orcaslicer has these built in. If Cura doesn't, you can get them from Ellis's excellent tuning guide.
Cura has plugins with the tests.
I'll second the other comment, Ellis's guide is where I learned the trick above from. 90% sounds like it's pretty low but I've had filaments and nozzles require as low as 83% for adequate results.