Hard removal sometimes requires glass polishing, especially when calcium and silicates have adhered to the glass in the sunshine for a long time. Fortunately, with the right products and techniques, residential and commercial windows can be restored to near new quality, provided glass etching hasn’t occurred. This video offers cautions and tips associated with professional glass polishing when working from the bottom of the window to the top of the window. The technique changes when one reaches a line of sight that is no longer in the shade but is in the direct sunshine. Coatings also affect the technique. This is a must see instructional video for all glass professionals using polishing techniques to remove hard water.