I am trying to print a rod end bearing on my ender 5. I started with a sphere inside and a matching surface with different clearances between them. I printed .2mm, .5mm, and 1mm clearance. The 1mm was too loose, the .2mm ended up fusing together so it would not rotate and .5mm was decent but still too loose. I am going to experiment further with different clearances and diameters to see if I can find the sweet spot.
Is there some kind of rule of thumb to go by on FDM 3d printers on what resolution they are capable of, or what is the minimum clearance before things fuse together? I am sure there is lots of variables to this, nozzle size, stepper motor resolution and reduction ratio. Would a smaller nozzle be the way to go on this or is it the printers resolution that determines how this will work?