This information is reprinted from the For Beginners column of Hand Papermaking Newsletter #34 (April, 1996).
Those interested in the papermaking process often focus on the preparation of materials and the forming of the sheets. The steps of the process which follow these, of removing the water from and drying the sheets, are equally important.
Sheets of handmade paper have been dried in a variety of ways. In many papermaking traditions, although not all, the papermaker places a stack or "post" of newly-formed sheets under pressure, which both strengthens the paper by increasing fiber bonding and accelerates the drying process by squeezing out large amounts of water. Presses range from boards with heavy weights (easily reproduced in a simple studio setting), to elaborate, large screw presses, to modern hydraulic presses. Most papermakers do not fully dry sheets of paper in a press, however, as air circulation and other considerations make alternative methods more practical.
Sheets of paper formed Nepalese-style, in which sheets are formed in a floating, cloth-covered mold, are dried in that same mold (and not pressed at all). In this tradition, the papermaker needs many molds, as each mold is in use as long as a piece of paper is drying on it. Usually sunlight and air alone dry this type of paper.
Asian papermakers sometimes dry their sheets by simply laying them on the ground. They use this method for papers which will become for wrapping, stuffing, floor coverings, or other utilitarian products which do not require a smooth, even surface.
Paper can also be dried sheet by sheet, with one side applied to a flat surface and the other exposed to the air. In India, for example, papermakers apply their pressed paper, still damp, to plaster walls. Elsewhere in India and in Japan, metal sheets, often heated from the other side, are sometimes used. Other, more traditional Japanese papers are dried on wooden boards. Contemporary paper artists use various surfaces for drying their sheets, including glass, formica, and linoleum. These all give the paper a two-sided quality: the side exposed to the air often softer and less compressed; the side facing the surface denser, smoother, and more regular.
Western-style papers were traditionally dried in sets of several pages together (called "spurs"), which were either clipped to or draped over hair ropes or wooden dowels, hung in well-ventilated rooms. After a certain amount of drying, the sheets were separated from the spur and rehung.
Most contemporary production papermakers making Western-style papers dry their sheets, after pressing, using forced air driers, which employ a series of sandwiched layers containing the damp paper, blotters, and corrugated or porous plates. These layers are typically put under moderate pressure and air from a fan or blower is forced through the entire stack, until the paper is dry. [See Claire van Vliet's article on this type of dryer in Hand Papermaking, Summer 1987, Volume 2 Number 1.]
Especially for paper made from fibers which exhibit high shrinkage, such as linen, papermakers should dry their sheets under pressure if they want to keep them flat. Otherwise, distortion, cockling, and other irregularities will appear in the dried sheets.
by Tom Bannister