We're ready to start sanding now and since I'm using a belt sander, I've set up a backstop on my bench to hold the board in place. If you don't do this, the belt sander will shoot the board down the other end of the shop and you'll be doing a lot of walking all day long. If you do use a polish sander on this you probably don't need a backstop. Sand the board with a gradual side to side and back and forth motion overlapping your strokes so you get nice even...[sanding board]. That looks pretty good. Do all of your lumber like that and then we'll proceed.