That's how I do it. I have an oak board, 3 x 1/2 x 36 which I ran through the drum sander to get it perfectly flat. Then Kenny M made me an assortment of tapered lams. I lay one of the tapered lams on the oak board then lay a 1/4" board which I want to taper on top of that. I make 2 or 3 passes then raise the belt up one turn of the adjustment handle and keep going till I have the board tapered to what I want. I scribe a squiggly line down the center of the board before I start, that way I can see where the taper ends. As I start the lam into the sander, I hold it tight on the feed end, then when there is enough sticking out the output end, I grab that end and hold it tight.