Tiny print!
edit: settings are .1mm layer 40mm/s filament is ESun PETG.
Wire splitter-retainer plug for a 3d printed LED ‘lightbulb’ for a 3d printed lamp. Not bad detail for .4mm nozzle. I have a .25mm, I need to set up one printer with that size for the small prints.
This was the first test, changed the model to print a little better with thicker walls in some areas that the slicer with a .4mm nozzle cannot resolve.
Should I try forcing the line thickness under .4 to like .3 and see what happens with a .4mm, or does that totally not work?
Just my two cents: line width (or “extrusion width”, as it is called in Cura) below your nozzle diameter doesn’t work too well at all - you won’t get a consistent extruded line, but only very intermittent, because there’s just not enough material pushed through your nozzle. Once, I tried scaling down a 200mm high vase, originally with 0.18 layer height and 0.65 extrusion width. But whatever I tried for the 50mm and 30mm versions, I just couldn’t get them to look clean with 0.1 layers and 0.33 extrusion width - holes at the most inopportune places, such as the thinnest spot of the neck, leading to them breaking there at the slightest provocation. Only after going up to 0.4, which is the same as my nozzle diameter, I got some clean miniature vases out of my printer, without “stuttering” in the walls.
So, TL;DR: line width < nozzle size: just doesn’t work out. 
