STUCCO FOR MOLDING RECONSTRUCTION - STUDENT HANDOUT

HIST GR8906: Craft and Science: Making Objects in the Early Modern World | Ephemeral Art in BnF Ms. Fr. 640
The Making and Knowing Project, Columbia University
Last updated 2021-09-24 by NJR

Ephemeral Art in BnF Ms. Fr. 640

The 16th-century artisanal/technical manual, BnF Ms. Fr. 640, contains hundreds of entries that describe making processes and techniques from the Renaissance. These include instructions for and observations about painting, gilding, arms and armor production, plant cultivation, and making molds and metal casts.

Among other topics, the manuscript offers insight into the cultural context, materials, and techniques of ephemeral artworks. Several entries in the manuscript aim to produce artworks that were intended to stand outside or that aimed to create the visual effect of a more permanent (and expensive) work of art. Explore the full range of topics in Ms. Fr. 640 in Secrets of Craft and Nature. A Digital Critical Edition of BnF Ms. Fr. 640.

Stucco for Molding

On folio 29r, an entry describes a process for making stucco to create “an ornament at little expense.”

Translation, folio 29r

Stucco for molding

Take tragacanth gum and put it to soak until, having drunk its water, it is swollen & rendered like jelly. Then grind it quite hard on marble & next take rye flour, which is better than wheat because it is more humid and does not make the paste as brittle, and sprinkle your tragacanth gum with it, & continue to grind and mix in thus, little by little, it and mix legi the very finely sieved flour. And knead it as if you wanted to make bread, until you you perceive that it has enough body & is as firm as bread dough that one is ready to put in the oven. This is recognized when it can stretch enough without breaking. And if it was not strong enough, it would not sti release well. Once the paste is prepared, rub the hollow form at the u with oil, with a brush, in order that the oil penetrates everywhere to make it release better, and press the paste inside quite hard. And if it does not release well, mix in more flour until it has enough body. With this you will mold whatever work you like, masks or garlands, which will be dry within one day. Next, you will apply them with strong glue or paste glue, as you like, and you will be able to paint and decorate them with gold & all colors. One makes ceiling ornaments with it in Rome. One can make bed ornaments with it.
If you want that the work stays white, it is better to mold with plaster instead of flour. It is true that it is more brittle and firm as well, but one needs to prepare it like this: temper it, when it is powdered strong, in a good amount of water so that it is clear, & grind it several times a day for fifteen days. Then pour off the water by tilting, and gather the plaster & grind it finely on marble, & place it in some kind of clean lead vessel, so that no dust & dirt falls into it, & leave it in the open air & in the serain for fifteen days with its water, and it will become matte, strong, white and light, very suitable for making a seat for burnished gold. And this, in powder form, you can mix, instead of flour, with tragacanth gum, and your work will be very beautiful. Lacking plaster, you can mix in well ground chalk or ceruse, & try bole & similar things. This stucco with the tragacanth gum has the quality that, yielding when it is not yet dry, it can be accommodated on either round or flat things, as you like. It is to make an ornament at little expense.

At the top left margin: Flour is not good in this, but chalk or ceruse is.

French Transcription (lightly normalized), folio 29r

Stuc pour mouler Ayés de la gomme dragant et la mectés tremper jusques à ce qu’ayant beu son eau elle soict enflée & reduicte comme gelée. Lors broyés la bien fort sur le mabre, & aprés ayés de la farine de segle, qui est meilleure que celle de froment à cause qu’elle est plus humide et ne rend pas la paste si brusque, et en saulpouldrés v{ost}re gomme dragant & continués à broyer et mesler ainsy peu à peu le et mesler legi la farine bien subtillement tamisée. Et la pestrissés co{mm}e si vous vouliés faire du pain, jusques à ce que vous vous cognoissiés qu’elle aye assés de corps & soict ferme comme la paste du pain qu’on veult mectre au four. Cela se cognoist quand elle s’estire assés sans se rompre. Et si elle n’estoict assés forte, elle ne se sti despouilleroit pas bien. Estant ainsy præparée, frottés d’huile le cave au u avecq une broisse affin que l’huile penetre partout pour mieulx faire despouiller, et pressés la paste dedans bien fort. Et si elle ne se despouille pas bien, meslés y encores de la farine jusques à ce qu’elle aye assés de corps. Avecq cella, vous moulerés fort net telle ouvraige, ou masques ou festons qu’il vous plaira, qui seront secs dans un jour. Aprés, vous les apliquerés avecq colle forte ou colle de paste, comme il vous plaira, et les pourrés paindre et estoffer d’or & toutes couleurs. On en faict les ornements des planchers à Romme. On en peult faire des ornements de lits. Si tu veulx que l’ouvrage demeure blanc, il vault mieulx mouler de plastre au lieu de farine. Il est vray qu’il est plus brusc et plus ferme aussy, mays il le fault præparer en ceste sorte: destrempe le estant en pouldre fort dans bonne quantité d’eau de sorte qu’il soict clair, & le broye plusieurs fois le jour l’espace de quinze jours. Puys verse l’eau par inclination, et ramasse le plastre & le broye subtillem{ent} sur la mabre, et le pose en quelque vaisseau plombé & net, qu’il n’y tombe aulcune poulsiere & ordure, & le laisse à l’air & au serain l’espace de quinze jours avecq son eau, et il deviendra mat, fort, blanc et legier, fort propre à faire assiete d’or bruny. Et de cestuy cy en pouldre peulx tu mesler au lieu de farine parmy la gomme dragant, et ton ouvraige sera fort beau. En default de plastre, tu y peulx mesler de la croye bien broyée ou de la ceruse, & essayer du bol & choses semblables. Ce stuc avecq la gomme dragant a cela de propre que comme il preste n’estant pas encores sec, il s’acommode ou sur choses rondes ou plattes, co{mm}e il te plaira. C’est pour faire un ornement à peu de frais.

Dans la marge en haut à gauche: La farine n’est bonne en cecy, ains la croye ou ceruse.