I noticed my Taz 4 having issues printing the bottom of fillets and circular parts. For example if I have a cube and all the edges are filleted the fillets on the bottom edge that would touch the glass will look like crap but the fillets on top will look great. I seem to have the issue with support material turned on or off.
I have included some pictures. The three circular objects were supposed to be round, the one in the middle is the original injection molded piece. Guess I should mention that I printed these two pieces laying down as they are shown in the photo. Granted the Photo is showing upside down for some reason.
This one is the bottom that has messed up the fillet, while the top looks good. I apologize for bad picture quality, this black plastic is hard to photograph.
Bad Corner, against the glass
Good Corner, top surface