I'm in process of sanding the deck and find that the random orbital sander leaves circular scratches in the epoxy. With enough sanding they tend to blend together but they are there never-the -less. my furniture experience suggests that these marks if on wood, will show through the varnish. Do they on the epoxy? Or do they just disappear?If they show, then do you all hand sand as the last sanding step or can you get to a fine enough sandpaper to make the circular scratches invisable. Thanks for your comments. Earl