The gang mill is regarded as possessing material advantages in the rapid and economical manufacture of lumber. Among the recent improvements tending to perfect such mills, those which are shown in the iron frame stock gang, manufactured by Wickes Bros., East Saginaw, Mich., are eminently valuable. Our large engraving represents one of these mills, constructed to be driven by belt, friction, or direct engine, as may be desired. The important requisite in this class of mills is such design and proportion of parts as will insure durability and continued movement at the highest speed, safely increasing the quantity and improving the quality of work done at a lesser feed, and admitting the use of thinner saws than is practical in the slower moving sash. These are among the advantages gained in the iron frame machine, overcoming the necessity of an expensive mill frame, saving time and expense in setting up, and avoiding the liability of decay or change of position.
IMPROVED IRON FRAME GANG SAW MILL.
Many improvements have been made in the mechanism of oscillation, and from these the builders of this mill have adopted what is known as the Wilkin movement, which oscillates the top and bottom slides. The top slides are pivoted at the top end, and the bottom ones from the bottom end, both being operated by one rock shaft from the center. This movement when properly adjusted gives an easy clearance and the easiest cut yet obtained. It adds no extra weight to the sash, and avoids the cumbrous rock shaft and its attendant joints, usually weighing from three hundred to five hundred pounds, which have been found so objectionable in many other movements. The feed is continuous, and is made variable from ¼ to 1¼ inch to each stroke, controllable by the sawyer. Power is applied to the press rolls in the double screw form with pivot point, also operated by the same hand. A special feature of this machine is the spreading of the lower frame so that its base rests upon an independent portion of the foundation from the main pillow block or crank shaft.
The solidity of the whole structure is thus increased, both by the increased width at the base and the prevention of connecting vibrations, which necessarily communicate when resting upon the same part, as in other forms of such machines heretofore in use.
The mill shown in the perspective view is one of twenty-six saws 4½ feet long, sash 38 inches wide in the clear, and stroke 20 inches, capable of making 230 strokes per minute. The crank shaft is nine inches in diameter, of the best forged iron. The main pillow block has a base 6½ feet long by 21 inches bearing, weighing 2,800 pounds. The cap is secured by two forged bolts 3½ inches in diameter, and by this arrangement no unequal strain upon the cap is possible. A disk crank is used with suitable counterbalance, expressly adapted to the weight and speed of sash; a hammered steel wrist pin five inches in diameter, and a forged pitman of the most approved pattern, with best composition boxes. The iron drive pulley is 4 to 4½ feet in diameter and 24 inches face; the fly-wheel six feet in diameter, and weighing 4,700 pounds, turned off at rim. When a wider and heavier sash is required, a proportionate increase is made in all these parts.
In the construction of the sash the stiles are made of steel; the lower girt and upper heads are made in one solid piece, without rivets, giving the greatest strength possible, with the least weight. The outfit also includes eight iron rollers for the floor, 8½ inches in diameter, with iron stands, and geared as live rolls when desired, a full set of Lippencott's steel saw hangings, and gauges for one-inch lumber. The weight of the machine here shown is 18½ tons. They are, however, built in larger or smaller sizes, adapted to any locality, quality or quantity of work desired.
It is said that the St. Gothard Tunnel is diverting the bulk of the Italian trade into the hands of the Belgians, Germans, and Hollanders with startling rapidity. Without breaking bulk, early fruits are taken from all parts of Italy to Ostend, Antwerp, and Rotterdam, whence they are carried by fast steamers to London and other English ports. But, on the other hand, Germany is sending into Italy large quantities of coal, iron, machinery, copper, and other articles of which the latter received nothing before. In two months alone, the Italians imported 1,446 tons of paper.