In order to make a plumb yourself, it is enough to hang any weight on a string, e.g.. scissors, screws etc.. I advise you to cut a four-pointed star from a thick sheet of metal. We tie the string to the upper arm, the lower one marks a vertical line. However, if we cut the star very carefully, the side arms will define a horizontal line perpendicular to the vertical. The longer the side arms will be, the more accurately we will be able to draw a horizontal line by marking the points at the ends of the arms.
