Iron shaper: a, b, fixed cutting tools. K, M, traveling bars.
Niles-Bement-Pond Co., New York.
Milling machine, R. K. Le Blond Machine Tool Co., Cincinnati.
A, table; B, overhanging arm; C, cutters; D, spindle; E, feed box.
In many cases the milling machine ousts the planer as much more economical. At the shops of the Taylor Signal Company, Buffalo, a miller of the Cincinnati Milling Machine Company does nine-fold as much work as a planer. It takes a first cut 1⁄8 inch deep across a full width of 12 inches, makes 60 revolutions per minute, feeds .075 inch per turn, giving a table travel of 41⁄2 inches per minute, with an accuracy limit of .001 inch.
Milling cutters with inserted teeth.
Cincinnati Milling Machine Co.
Now for a glimpse of what a great inventor had to suffer because he lived prior to the era of machine tools, before the days, indeed, of that indispensable organ of the lathe, its slide rest. The first steam engines of James Watt built at the Soho Works, near Birmingham, are thus described:—“A cast iron cylinder, over 18 inches in diameter, an inch thick and weighing half a ton, not perfect, but without any gross error was procured, and the piston, to diminish friction and the consequent wear of metal, was girt with a brass hoop two inches broad. When first tried the engine goes marvelously bad; it made eight strokes per minute; but upon Joseph’s endeavoring to mend it, it stood still; and that, too, though the piston was helped with all the appliances of hat, papier maché, grease, blacklead powder, a bottle of oil to drain through the hat and lubricate the sides, and an iron weight above all to prevent the piston leaving the paper behind in its stroke—after some imperfections of the valves were remedied, the engine makes 500 strokes with about two hundred weight of coals.” In another month or two, with better condensation, it “makes 2,000 strokes with one hundred weight of coals.”
Milling cutters executing complex curves.
Brown & Sharpe, Providence, R. I.