One of the most difficult aspects of wood preparation is knowing how much to sand to remove all the machine marks and other flaws. Here’s a trick that may make it easier.
Draw some pencil marks on the wood. Then sand the wood until you have removed them entirely.
Sanding is very personal. We all sand differently. We use different grits, more or less pressure, more or fewer passes and with more or less wear on the sandpaper. So you may determine that, for you, sanding off the pencil marks once is enough. Or you may determine that drawing a second set of marks after the first has been removed and then sanding off these marks works better. In other words, doing it twice.
