The masterpiece was made in 1464-1470 by Hans Duringer.
The masterpiece was made in 1464-1470 by Hans Duringer.
The conservation of the clock started in May 2019. The object was cleaned from overpaint, then consolidated and some of preserved original parts of the framework were reassembled. To cover not original tree, leaves and apples were added. To cover the clock's base, an extra wooden covers were assembled. Some sculptures which were reconstructed in the nineties of XX century were corrected, for some like death and Madonna new polychrome was made. Adam, Eve, angels, deacons and snake's head were disassembled and will be replaced with new ones in 2020.
As usual blue paint was prepared with azurite and applied on gray layer [sample 1]. Green parts of the clock's architecture were firstly covered with minimum layer [sample 2]. Paper stars were gilded and then glued onto the clock's surface. Silver leafs were burnished on bole/gesso layer [sample 3].
Cross-section from planetarium background shows paper star covered with silver. Stars were glued on the clock's surface before last lacquer were used.
With deionized water and Shellsol T were chosen to remove dirt from surface.
To uncover original decoration, dull overpaint was removed.
The original paper stars were first examined. The best quality cotton paper with a weight of 80 g was chosen.
As in the pattern, a layer of glue from rabbit skin was applied, followed by a primer, a white bole and a final red or yellow bole layer.