Page 317 - Green - Maritime Archaeology: A Technical Handbook. 2nd ed

296 Maritime Archaeology: A Technical Handbook, Second Edition
be totally dry before pencil construction lines can be erased. A hair dryer can be useful to speed the drying process. Finally, plastic is a very expen- sive drawing material, but its use is strongly recommended for all perma- nent recording work.
Other tracing papers include the cheap tracing papers of the grease- proof paper type. They take India ink extremely well, but are not dimen- sionally stable, and are particularly affected by humidity. In the latter case, if they get wet, a valuable drawing that has taken many hours to produce can be ruined. As it is very cheap, about one quarter the price of plastic film at the time of this writing, it is ideal for producing preliminary drawings and tentative construction plans.
B. PAPER
White cartridge paper is often used for drawings and has the advantage that the ink takes well on it. The main objection is that corrections are dif- ficult, particularly as either the paper is damaged if the ink is removed, or the porosity of the surface is altered if a white opaque covering paint is used. Drawing paper comes in a variety of grades of loading, so that those with the greatest loading have the smoothest surface. It is necessary to use care in the selection of paper. The rougher paper allows inks to run whereas paper with a lot of surface additives causes pens to clog and gives rough lines. Bristol board has an excellent surface for line drawings. There are also white plastic drawing papers made from the same materials as the drawing film. These have some of the inherent problems of film, but are extremely strong and robust.
Some very effective artifact drawings have been published using white scraper board (Kaijser, 1981). The scraper board is a card with a special surface, usually black, which when scraped with a needle or scalpel reveals a white surface. It is possible to either use a white scraper board and scrape to reveal the black, or to use a plain white surface, block the object in India ink, and then scrape this to reveal the white below. Draw- ings made on scraper board can have interesting surface effects which can make the material of the object, glass bottles, for example, look particularly realistic.
Graph paper usually comes in blocks of A4 or larger formats or in rolls 750 mm to 1 m wide in a variety of lengths. It can be opaque or transparent and is available in a variety of colors. However, graph paper, particularly in roll form, can be inaccurate; for example, one particular grade was over- sized by +0.15% longitudinal and +0.25% in the lateral direction. One useful aspect of colored graph paper is that with a judicial choice of colors,