SHINGLE-MA KING MACHINERY. In the manufacture of shingles nearly every machine, except for jointing the butts, is a sawing machine; the difference being as to whether the saws are on vertical or horizontal arbors, and whether one saw takes care of one or more than one block. Machines with two or more saws cut from four to ten bolts at one time. The machines of smaller capacity usually present the bolt to the saw and wit hdraw it by a reciprocatingmotion. those cf larger capacity using a rotary motion. Among the former, the points of difference are as to whether the block is presented end on or side on; and in minor details of varying the taper, thickness, etc.
For making sawed shingles there are of machines. One of the most simple has a circular saw upon a vertical arbor, belted from below, and a sliding carriage presents the bolt endwise to the saw, so as to cut with the grain of the wood instead of across it. This table or carriage has an adjustment by which either the front or the back end may be tilted, so as to saw a shingle which is tapering in its length ; and there is provision for changing the thickness of cut without altering the taper, or for varying both. Such a machine will cut 3,000 to 4,000 cedar shingles per hour; and it is also adapted for sawing heading and box stuff.
In the shingle machine made by Adams & Sons the saw arbor is vertical, and the block or bolt is borne between dogs at the end of an arm vibrating in a horizontal plane and present ing the side of the block to the action of the saw. The taper is given by tilting one end of the table bearing the block by a foot lever ; this gives the requisite degree of taper to one shingle, and the table being brought back by a spring when the foot is taken off the treadle after one shingle is cut, the next shingle is cut with the butt coining at the opposite end of the bolt from that. of the first one cut. Thus every other shingle has its butt to the right ; and the saw cuts slanting at every other cut, and parallel on the intermediate eats.
A shingle and head-cutting machine bro»ght out by S. Adams & Son has the axis of the circular saw which does the cutting inclined slightly from the vertical, and the top or table is semi-circularly inclined from the horizontal. Along the top there slides a clamping table which holds the bolt which is to be cut; the bolt being placed crosswise of the machine so that its side is presented to the action of the saw. The bolt being clamped at the lower end of the inclined table, every time that the table is drawn forward the shingle or heading is sliced from it, and drops clear of the saw. There is suitable adjustment for giving any thick ness or degree of taper, and the machine will cut with the belt first on one end of the block and then on the other, or may be set so as to cut the butts continuously from either end, as desired. The capacity claimed is 3,010 shingles per hour from suitable blocks, or GO shingles per minute from blocks 8 in. wide. The carriage is moved up over the saw by a pinion run ning in a rack gear until the saw has passed through the block, when the pinion is automat ically released and the carriage moves back by gravity. Then the dog opens, the bolt or block drops on the platform, which is tilted by a ratchet wheel, the pinion engages the rack again, and the carriage moves the block against the saw. There are two feeds, one for hard and the other for soft wood.
In one of the most important of the shingle-cutting machines made there is a large horizontal disk, driven by gearing over the top of a frame having at two op posite points in its circumference a circular saw. The disk has dogging provision for ten bolts at once, and each of these is brought in turn to first one and then the other of the horizontal circular saws, making a shingle from each bolt at each presentation to the saw, or twenty shingles for each rota tion of the circular traveling table. There are several modifications of this machine, which is made by Perkins & Co.