Stringers are extended by gluing them to each other for raising the length up to the whole length of the boat. Before lengthen the ends of stingers must be sawn to sharp angle (4-5 times length than the width of the stringer) for increasing the surfaces to be glued. To reach the well connected surfaces the cutting operation must be executed precisely. This way I made a pattern installed onto the saw to get the appropriate and same angles.
