I have attached a simple drawing of a winch that I would like to design. To get the size of the spool, hydraulic motor and winding arm correct, I need to figure out the formulas to calculate the torque needed to rotate the winding arm and the forces on the rope at each section. (ie. W,X,Y and Z where Y and Z are the spool empty (y) and the spool full (z). The reaction load at W is 250 lbs. Think of this as a large fishing reel that you can cast line out and reel it in. This is the style of winch I want to design, but I need to know the formulas to calculate the forces on the rope to then optimize the design and size the hydraulic components. Can anyone help me with the pulley formulas to calculate the forces, assuming all the angle changes are friction free?