贴广告牌墙面如何找中间位置

Does it have a certain impact on marble to stick billboards on marble walls? According to the query of relevant public information, the billboard is fixed with angle steel welding to the advertising frame, the location where the billboard is to be installed is determined, the entire stone is removed at the fixed point, and the advertising frame is fixed with angle steel welding. The advertising rack must be connected to the steel structure with an angle steel of more than 30 degrees. When positioning, try to allow the advertising rack to cover the space left by removing the stone. Clarify the installation sequence: column hoisting, billboard frame installation, billboard surface installation, and sporadic component installation.