05-10-2020, 11:40 PM
You have a good start the timber looks to be good. The legs protrude through the cover and are for standing the seat on the floor. The wings remain under the cover and are to fill out the corners which would collapse under the tension of cover fitting. I would keep the springs if not pitted, for a superior 'feel' when seated. I would replace the hessian as it is probably brittle after so many years. All your clues are in the old cover, note that a plain unpleated section at the bottom will make stapling on easier and it is sometimes holed below the visible to enable the cushion to breathe when sat upon.