Polygonal astrolabes
Erasmus Habermel is known for his highly unusual polygonal astrolabes, but he was not the only one, and perhaps not the first. In a bound collection of 16th-century instrument prints mostly representing the copperplate work of Georg Hartmann there is a woodcut of the reverse of an octagonal paper astrolabe (not necessarily by Hartmann).
See [Collectio figurarum], Eine reiche Sammlung von Kupferstichen u. Holzschnitten, welche Sonnenuhren u. andere astronomische Instrumente darstellen
Bayerische Staatsbibliothek
Shelfmark: Rar. 434, f. 30
http://daten.digitale-sammlungen.de/bsb00028171/image_57