The back of the sofa collapsed. Prepare a needle and thread and four buttons, unzip the sofa cushion, take out the filler, and sew the buttons on the sofa cover. The position of the four buttons should be like this. Compare the front and back in pairs, and push the buttons as close as possible. Then, the filler is stuffed into sofa cover.

If the base collapses, turn the sofa over and check whether the canvas belt or nylon belt is broken. If it is broken, it should be replaced. When replacing the belt, the two ends should be nailed to the wooden frame, the two ends of the belt should be folded three times, and the nails should be nailed into a cross. Nail the seat frame with a 5 cm wide wooden Fang along the bottom belt. If the spring is broken, it should be replaced with a new one. First, fix the spring on the wooden Fang with small nails according to the drawing, and then tie the spring into an "M" shape with hemp rope or nylon rope. The tied spring should be high in the middle, low around, high in the front and slightly lower in the back. When replacing the sack cloth, put in fillers such as miscellaneous felt and foamed plastic in turn, then cover the cloth, and fix each layer with nails, paying attention to the feet and shape.