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Chapter 11: Artifact Drawing 293
text running vertically. Otherwise the landscape plan will have to be printed across the portrait format, resulting in loss of detail. The next consideration is that the finest printable line is about 0.1–0.2 mm, depending on the quality of the paper and printing process. The 0.1-mm line is really very fine, so it is better to aim for a minimum printed line thickness of 0.25 mm, which on the working drawing is a 0.5-mm line. Similarly, if the drawing is to be reduced four times then the line thickness would have to be 1.0mm. However, drawing for a 4¥ reduction is not easy, as one has to ensure that shading and line separations are wide enough so they are not clogged on reduction.
The artifact is generally drawn in an orthographic projection from as many viewpoints as is necessary to adequately illustrate the object. Thus, the drawing must show sufficient projections to allow any dimensional mea- surement of the object to be taken from the drawing. In other words, the drawing should provide enough information to be able to make a recon- struction. It is unnecessary to produce every projection of the object if this simply duplicates information that is already there, although additional pro- jections may be of help to better visualize the object.
An orthographic projection has no perspective in it. Thus, as in any engi- neering drawing, distances on the plan are distances on the object. Usually, the object is illustrated with either a front elevation or a plan.
A difficult question is: Does one illustrate the object as it is, or as it should be? First, it is important to distinguish in the drawing between what exists and that which is reconstruction or guesswork; thus solid lines delineate the existing object and any guesswork is indicated by a spotted or hatched line. Where an object is damaged, flawed, or misshapen in its original manufac- ture, a decision has to be made to either show the object as it was meant to be or present it in its flawed state. It may be that showing the flaw will be useful because it helps in the understanding of the manufacture of the object. In the case of damage that has been sustained during or after the point at which it was abandoned, e.g., a rudder gudgeon bent in the process of the shipwreck, then it may be of more use to illustrate it in its original form, but also record which particular side was damaged, as this may help in the interpretation of the wrecking process. If it is possible to reconstruct an object in a drawing without guesswork, then this is preferable as it will make the object more understandable. If it is not possible to achieve this, then the object should be drawn as is. In complex situations, the object may be reconstructed in the drawing and then supported with a photograph.
Illustrating appendages to symmetrical objects can be difficult. Handles on pots or jars, for example, are a problem; if there is more than one and they are symmetrical, then one can be drawn in profile and the other as an exterior view. If there is a single handle as, for example, on a beardman jug,





























































































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