When printing an object on an FDM printer, is it easier to sand and fill thick layer lines than thin layer lines for low detail objects such as small plates for cosplay armor (Under 6 inches in size per print), in order to get a good finish?
PLA, Ender 5.
No. The outside of the layer has a round cross section, so the higher the layer, the larger the semi circle cross section and the deeper the valley is between layers.
Fine layers take forever to print large objects though, so for making costume parts I would go max layer height. To get a good painted finish you don’t need to sand to the bottom of the valleys though. Sand the high spots so about 50% of the layer edge is flat, then use automotive “high build primer”. Paint it on thick and don’t worry about runs. The high build makes the paint fill in the valleys. Sand it again, down to when it’s smooth, or when you’ve exposed the plastic of the high parts of the layers. Can do it again if it’s still bumpy. Then regular primer (recommend same brand/line as the high build for chemical compatibility), light sand, and paint. If you sand with fine grit between layers of paint you can get a very impressive finish.
The key ingredient for nice paint is the high build primer, it is a great companion for FDM printers. They generally have it at the auto parts store, rather than the hardware store.
