Completing parchment manuscripts that have been biologically damaged is a very complicated task, particularly for severely damaged leaves. In 1983, experiments on completing parchment leaves by manual casting started in the Hungarian National Library (Országos Széchényi Könyvtár). The aims were to join the lacunae of the extremely weak manuscripts, simultaneously to consolidate the parchments and to fix the inks and pigments on the support. Pulp composition was based on physical examination of the final product, aesthetic considerations, and ease of casting. This article presents the details of the procedure.