Here are a few details about stencil art techniques in 1930s gleamed from the letters of Marcel Duchamp. At that time stencils were used as an alternative to expensive color printing processes to produce add colors at an affordable price. Duchamp was using professional stencil men in 1934 preparing a stencil reproduction of the Large Glass for his Green Box and, in 1937, to arrange printing of Katherine Dreier’s 40 Variations.
To Henri-Pierre Roché, Paris, 18 May 1934 “…with my stencil man. We’re having a lot of trouble and I have to make him another tracing of all the stencils he’s to make in order hopefully to achieve a result.” (p.189)
To Katherine Dreier, Paris 25 June 1937 “The news are good but slow – Naturally the printing in black of the lithograph was finished long ago – and the 3200 prints taken to the ‘colorist’ who expected to finish in a month. I called him up yesterday and I am to see, in a few days, half of the whole work cut our and ready for color-brushing. This means that his main work consists of cutting out in the zinc foil the areas for each color – The actual brushing of the color does not take much time. Anyway we will have to wait until August before his work is finished.” (p.212)
It seems safe to assume that a “colorist” and a “stencil man” (“homme du pochoir”) are the same. The use of “zinc foil” for the stencils makes sense given the number of prints to stencil and plastics were still being invented. The color is brushed through the stencil and not sprayed because aerosol paint cans were not invented until 1949.
All quotes are from Affectionately, Marcel – the selected correspondence of Marcel Duchamp, edited by Francis M. Naumann and Hector Obalk (Ludion Press, 2000)