Check "Inset Surface" in KISSlicer

thingiverse

This model help to decide the setting of "Inset Surface". If these two model can fit to each other, not too tight or too loose, that means you get correct setting of "inset surface" for your machine. Left pare in the picture, is a good mach. Need only a little force to push them fit each other.The right pare have too much "inset surface" and can't hold each other.