Few documents have survived which describe how medieval winged altars were constructed. One is inclined to begin from the construction methods used in architecture today, however, the legibility of medieval orthographic drawings is hidden in the geometrical relationship of the sections of varying length. The major points of a building and the profiles of the stones were constructed from a single dimension - often one side of a regular polygon - with the help of compasses and a ruler. This method may be considered a common one and can be deduced in the works of the altar building workshop of the Szepesség in the 16th century. Several examples are provided to prove that a single segment, that may be identified as a characteristic detail of an altar, can be the starting point of a full reconstruction procedure. See also AATA 21-490.