Once you have both sides equally sanded, then it's time to finish the crown. Back on the belt sander, you place the paddle on the belt the same direction as you started with, and slowly, very slowly start rolling the paddle down towards the center line. Keep rolling it back and forth until you get all of the untouched wood rounded off too the center line on both sides, but leave your center line on, get as close as you can without sanding it off. Once you have all the wood rounded off with your center line still left, then start sanding the center of your paddle, by rolling it back and forth from one edge to the other side edge. Watch out for your finger tips and finger nails, you will sand them off too
. Keep working that paddle back and forth until you have a nice even crown on it from the screw end to the tail end of your paddle, be carefull not to sand it uneven. Make sure you go slow enough to keep the thickness of your paddle even the full length of the paddle. Check the bottom of your paddle frequently to make sure you don't have any flat spots or edge rails on it, rock it from edge to edge when your crowning it.