Finishing

As far as I can tell, there is virtually nothing out there on Medieval/Renaissance furniture finishing (but I'd be more than happy to he proved wrong). Most sources suppose some sort of beeswax/oil/turpentine mixture or paint, but I haven't seen this documented to my satisfaction. For that matter, I haven't found anything on period furniture paints either.

Oil

There are several alternatives in an oil/wax finish. One can use boiled linseed oil either straight or cut with a little turpentine. One can melt beeswax into the oil/turpentine mixture (carefully! this stuff is highly flammable). As an alternative, the beeswax can be grated finely (e.g., with a cheese grater) covered with turpentine and left to dissolve for a day or two.

Safety note - oily rags have a nasty habit of spontaneously bursting into flame when drying. Used rags should be disposed of properly - either by storing in water or in a fireproof container (preferably outside!).

Paint

Paint is a combination of a pigment, a binder to hold the pigment to the painted surface, and a liquid vehicle to help the paint flow. The type of paint is usually distinguished by the binder. Types of paint known in period include:

Oil

Oil based paints use a drying oil such as linseed or walnut oil and a thinner (usually turpentine). Salzman documents the use of oil-based paint for interior woodwork back to XXXX.

Tempera

Tempera is based on egg yolk or egg white and water.

Distemper

Distemper is a mixture of glue (generally hide glue) and water.

Casein

Casein or milk paint is made principally from milk, lime, and water. It produces a very tough surface. Despite numerous sources that insist that milk paint has been used since remote antiquity, I haven't found anything to indicate that it was (or wasn't) used on period furniture.

All of the paint recipes I've been able to find are for artist's paints. The sources indicate that high-style furniture (e.g. Italian cassoni) were decorated by artists using the same materials and paints used for panel painting (i.e. a gesso base with either egg tempra or oil paint). What I haven't been able to document are the paints used for lower end furniture. Chinnery states there are no sources for furniture paint formulations before about 1660.

Varnish

Varnish is a combination of a resin such as copal, damar, or pine resin and a solvent such as alcohol, turpentine, or oil. Various varnish recipes are known in period, but I haven't been able to document their use on furniture although they were certainly used on paintings and musical instruments. Salzman documents the use of varnish on interior woodwork in XXXX.

Shellac

Shellac is the dried secretions of an insect native to the Indian subcontinent. It is dissolved in alcohol for application. I haven't found anything on the use of shellac in period. Some comments I've seen lead me to believe that it first appears in Europe in the 17th Century.

Sources

Cennini, Cennino d'Andrea.
The Craftsman's Handbook: "Il Libro dell' Arte", Cennino d' Andrea Cennini, Translated by Daniel V. Thompson, Jr. New York, Dover. 1954

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Chinnery, Victor.
Oak Furniture: The British Tradition. Woodbridge, Suffolk: Antique Collectors' Club, 1979.

Salzman, L.F.
Building in England Down to 1540: A Documentary History. Oxford: Oxford University Press, 1992.

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Theophilus.
On Divers Arts: The Foremost Medieval Treatise on Painting, Glassmaking, and Metalwork. New York: Dover, 1979.

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