Metal bar securing log is a log dog. Use a felling axe to drop tree and cut to the line then remove slabs off the side of what will become a beam,step,wall log,trim piece or floor joist ect. with a broad axe. A curved handle helps avoid hitting knuckles. An adze could be used for final leveling of flat surface. Timbers could be flat on any number of sides depending on application. Economy of labor a factor for sure.A women wanting flat walls vs a man wanting a build finished may have generated a couple discussions. l.o.l..
Bigger sized axes were for larger work ,for example sills for a cabin or home.Often one side of axe is flat and opposite side contoured with straight side against line. Hew to the line!