. Canadian forest industries 1897-1899. Lumbering; Forests and forestry; Forest products; Wood-pulp industry; Wood-using industries. Fig. 5 F&.6 Specimens of Perforated Saws. since to prevent cracks from forming in circular cut-off saws. This was done as the result of an investigation into the cause of these cracks and the result arrived at independently of any know- ledge of Gove'e invention. A practical test not only established the efficiency of the remedy as to the prevention of cracks, but incidentally con- firmed the value of Gove's proposition. The saws run lighter, cut smoot
. Canadian forest industries 1897-1899. Lumbering; Forests and forestry; Forest products; Wood-pulp industry; Wood-using industries. Fig. 5 F&.6 Specimens of Perforated Saws. since to prevent cracks from forming in circular cut-off saws. This was done as the result of an investigation into the cause of these cracks and the result arrived at independently of any know- ledge of Gove'e invention. A practical test not only established the efficiency of the remedy as to the prevention of cracks, but incidentally con- firmed the value of Gove's proposition. The saws run lighter, cut smoother, and alweys cut squarely. Thirty years later J. E. Emerson, of Trenton, , brought out a circular saw with a series of holes or perforations extending from the gullet of the tooth some distance into the body of the saw, as shown in Fig. 3. This was designed to facilitate in gumming out the saw, and was cal- culated to save time and labor. At that day the modern emery saw gummers were unknown, and saws were kept in shape by filing by hand or being sent to a saw factory from time to time to be gummed out under a punch press. It can readily be seen how well contrived this plan was to the prevailing conditions. It also served to keep the periphery of the saw cool, and thus added to its efficiency. Saws of this description are still in use, and the design has proved to be of permanent value. In 1867 I. J. Lockwood designed a circular saw with radial slots located at the centre of the saw blade, as shown at Fig. 4. This was the reverse of the Gove effort, and aimed to keep the saw free from buckle when cool on the rim and heating at the centre, Large numbers of these Brooklyn pattern, in which the holes pierce the saw blade at an oblique angle. These saws were termed " ventilated saws," and no one will be likely to object to the term. The designer in- tended to keep the saws cool by inducing air currents to flow through the holes when the saw was in use. The inclined
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectforestsandforestry
