. Canadian forest industries 1910. Lumbering; Forests and forestry; Forest products; Wood-pulp industry; Wood-using industries. 2.—Diagram Showing Motion of Pit Saw. 3.—Proper Shape of Pit Saw Teeth the English gate, with one saw ; third, the muley saw; fourth, the cir- cular saw; fifth, the gang of a number of saws, both straight line and Kendall oscillating, and last, the band saw, both single and double cutting. In the near future another great change will have occurred, when the power for driving the saws will be electricity. I will take up the different subjects as enumerated above, the f
. Canadian forest industries 1910. Lumbering; Forests and forestry; Forest products; Wood-pulp industry; Wood-using industries. 2.—Diagram Showing Motion of Pit Saw. 3.—Proper Shape of Pit Saw Teeth the English gate, with one saw ; third, the muley saw; fourth, the cir- cular saw; fifth, the gang of a number of saws, both straight line and Kendall oscillating, and last, the band saw, both single and double cutting. In the near future another great change will have occurred, when the power for driving the saws will be electricity. I will take up the different subjects as enumerated above, the first being the pit saw. I enclose a few sketches, to make the meaning clear- er. We have learned that the first pit 6aws used in Canada were made parallel, about 4 inches wide and 5 feet long. On account of their being so narrow they were hung in a frame made of wood. The frame w as about 3 feet wide between the stiles and iron stirrups were attached to the girts or cress pieces at both ends to strain up the saw. The weight of the saw together with the frame and iron hangers made this contri- vance very heavy. It would weight 25 or 30 pounds. Some might say that if it were even heavier it would be so much the better, for the extra weight would serve to help force the saw down through the cut. But we have found in practice, that the less weight we have, providing the teeth of the saw are made the proper shape and kept sharp, the better. I have found in a long experience that teeth shaped as in diagram No. 3 are the best for all kinds of timber, both hard and soft. We find many saws coming from the shop with teeth as in diagram No. 4. I never could make them do good work in any kind of timber. In diagram No. 2 I have tried to show the proper motion a pit saw should have. We will start at the extreme upper limit of the stroke, and follow the dotted line on A, at the same time following the arc of circle on B to the down limit. Line C shows the edge of the saw commencing the do
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectforestsandforestry
