Page 318 - Green - Maritime Archaeology: A Technical Handbook. 2nd ed

Chapter 11: Artifact Drawing 297
film, and filter, it is possible to photograph an object drawn on graph paper so that the lines do not show. Thus the grid can be used as a reference when making the drawing and it is possible to dispense with mechanical drawing aids.
C. INKS
Most drawing ink manufacturers provide inks for various uses. The type of ink selected will depend on the type of pen and the type of surface to be used. It is helpful to remember that certain inks are compatible with par- ticular pens, and mixing different inks in the pen reservoir should be avoided. In particular, etching inks can dissolve parts of certain types of pens.
D. PENS
There is an immense variety of pens for drawing purposes. They may be divided into four categories each of which is described next.
1. Dip Pens
Dip pens are used for simple artwork. Usually, they are obtained either with italic, straight-cut nibs to give different thicknesses to different parts of the letter (like Roman typeface or italic handwriting). The also come with nibs with a disk end which give lineal letters with equal thickness through- out, although the ends of letters are round-ended not square.
2. Stilo Pens
Stilo pens are produced by a number of different companies. In general, these are based on a holder with a screw-in pen tip and ink reservoir. The pen tip consists of a hollow tube with a flat end. The ink flows from the reservoir down the fine tube to the flat surface at the end of the nib. When the pen is drawn on the surface of the paper, the ink flows out across the flat nib surface giving a line equal in thickness to the tip diameter. The tips range from 0.13 to about 2.0 mm (in the DIN system the double increments are 0.18, 0.25, 0.35, 0.5, 0.7, 1.0, 1.4, and 2.0mm). Down the center of the tube is a fine wire, the upper end of which is attached to a little cylindrical weight. This acts to control the flow of ink and to help unblock the pen when it clogs. Thus, by shaking the pen back and forth, or screwing the cap