Frames and supports in 15th and 16th-century Southern Netherlandish painting

MATERIALS AND MEN 29 The main types of saws have existed since antiquity. A saw contains a metal blade which is toothed on one side. The saw teeth form triangles and in general it is the shorter side of the tooth, set more perpendicular to the blade, which bites into the wood when the saw is pushed. The cutting edge was sharpened with a file (fig. 6: 40-42). The teeth are inclined alternately to the left and right of the axis of the blade to form the “set” which allows the blade to pass easily through the wood and remove the sawdust. This set was produced using a saw-setter (fig. 6: 14), a flat piece of iron with several notches which served to grasp the teeth of the saw and move them alternatingly to the right or left in a process known as “setting” a saw. Other more rudimentary methods were also used, like inserting a chisel between two teeth and then turning it or hitting the teeth alternately in one direction and then in another. The shape of the teeth of a saw and the set were determined according to the function of the saw. There were various types of saws. Hand saws, used for example to shorten boards, had rigid, slightly arched and pointed blades. The widening of the blade between the toe of the blade and the handle prevented the saw from digging in too deeply. For jobs that could be done by one man alone, the blade was inserted into a single wooden handle (fig. 6: 15). The handle was often long enough to be held with both hands. This could be necessary. Early depictions show blades of up to 1.5 m in length long. The smallest hand saws were the size of a modern knife (fig. 6: 16). Sometimes the blade was very narrow in order to reach hard-to-access places. This pad saw or key saw seems to have appeared in the late 15th century. At the end of the 16th century the handle could adopt a curved shape (fig. 6: 17). For heavy work, such as sawing logs across the grain, the long blade was provided with a handle at each end and was operated by two men (fig. 6: 18). These handles were in the axis of the blade. With the handle perpendicular to the axis of the blade (fig. 6: 19), this saw could also be used for cutting logs longitudinally. But its use for this purpose became generalized only in the 18th century. Frame ripsaws: for sawing tree trunks lengthwise, sawyers generally used a saw with the blade set in the middle of a wooden frame (fig. 6: 20). This saw was operated by two men, working either diagonally or from top to bottom. The saw bit into the wood on the downstroke, along a line marked with a plotting string or marking string, a piece of string that was dipped in a container filled with chalk, and then stretched along the wood at the desired location. When drawn and released like a bowstring it left a coloured line on the wood (fig. 6: 23). The topsawyer also had the important task of guiding the saw so that the board was of even thickness. At the end of the downstroke, the bottom sawyer’s job was to loose the saw from the cut, to help the top sawyer pull it up. From the later Middle Ages onwards, a device was generally fitted making it possible to change the angle of the blade. In the 18th century a device was added for retightening the blade, a device that does not appear to exist in the 15th and 16th centuries. In the 18th century woodworkers also had rip saws, smaller than the sawyers’ version, but Roubo reported that they took three times as long as specialized sawyers to do the same work and did so only when there was no reason to call in sawyers.