There is no written evidence that Dürer and other artists used the help of construction frames. But there is a clue in the manual for drawing horses, Die Proporcion der Ross, by Hans Sebald Beham (1500–1550), published in Nuremburg in 1528. Although the work was immediately confiscated on suspicion of plagiarism, Beham later integrated his instructions in Das Kunst und Lere Büchlin of 1546 / 1552. He believed that for art it was necessary once again to learn to measure with the compass and work with construction lines.

Beham recommended constructing proportion diagrams with nine fields. Within the grid, further subdividing construction lines and a diagonal should be drawn as well as “Pünctlein” (little dots), to be placed on precisely designated lines. From these dots the strokes of a compass would pre-determine specific contour segments of a horse, which would later be expanded into the whole outline of the animal’s body. [1]

A further indication of the actual use of the construction methods presented by Dürer is provided by a drawing by Hans Baldung, known as Grien (1484 or 1485–1545), depicting the dead Erasmus of Rotterdam. In this study, Baldung placed an (irregular) grid over the head of the deceased. He inscribed a circle within it and intersected it with diagonals. In doing so, the artist verified the proportions of the dead man, apparently in search of regularity and harmony. A UV image makes this procedure more clearly visible. [2]

In the work of the Italian sculptor and art theorist Lorenzo Ghiberti (1378 – 1455) can also be found a clue about grids for heads. In the third commentary of the unfinished Commentarii, which discusses a modular system for the body of a man, is written: “(...) we begin with the measure of the head and draw each section of it in its height and divide said head into nine squares (...).” [3]