the aluminum-plastic plate door head can be used without priming, with 2*4 galvanized iron pipes and welded keels, and the sizes are evenly distributed, that is, the size of an aluminum-plastic plate is 121.5*242.5, which is reasonably arranged and cut equally. When installing the aluminum-plastic plate, it is best to reserve expansion joints, and each plate is cut diagonally, so it is best to keep each plate with even gaps. The bottom layer is temporarily fixed with double-sided tape and then coated with 995 software, glue and the protective film outside. In summer, it is best to cool for one day and install the words on it the next day, so it is not easy to leak. This is my installation experience for several years. When installing in winter, the protective film should be removed first, which can improve work efficiency. (Pay special attention, after the galvanized pipe is welded, it must be polished flat, so that the signboard will be flat.)