Finally returning to our discussion on hand planes we pick back up by talking about the roughest planes on the bench. The Jack Planes! This class of bench plane falls between the large jointers and the smaller smoothers, but they're the perfect size for doing rough work without wearing out the user. In the Stanley-Bailey numbering system the Jack Planes are the No.5's, No.5, No.5-1/4, No.5-1/2. But in case there's no number or it's a wooden bodied or you're just not sure, the Jack Plane is easy to identify by its size - approximately 9-12 inches in length. Again, not to long, but not to short! The Jack isn't a plane built for beauty, so if you're picking one up second hand don't be surprised if it's really, really beaten up. But don't worry, it'll work amazing.