The Automatic tuning Mac/rine shown in Fig. 2 is specially designed for making carriage and wagon hubs up to 20 in. diameter, and 18 in. long. It receives the blocks in the rough state, roughs, turns, cups, finishes the ends, cuts the beads and shoulders for the bands, and makes the hubs of any shape or size, at one operation. The table is built in two parts. The lower half is gibbed and fitted to the frame in V-shaped ways, with adjustment horizontally in line with the mandrel, by hand wheel and screw. to center the knives with the hub block. The upper table, with roughing and finishing knives at either end, is mounted upon and gibbed to the lower table, and slides from right to left at right angles with the mandrel by turningthe large hand wheel, to bring either the roughing or the finishing knives to the hub block. The roughing knife, with a straight face 18 in. long, is held in a stand at the back of the sliding carriage, with its cutting edge extending downward, and when working takes off surplus material from the hub block in the form of a ribbon in. thick, the full length of the hub ; the gauge governing the depth of cut or feed. The finishing knives are at the opposite end of the carriage from the rougher, with their cutting edges extending upward, consisting of a body knife with a cutting edge shaped to correspond with the style of hub to be turned ; and a flat knife at either end upon the same stand, for cutting the front and back bands, with adjustment for cutting hands of different widths and diameters. The cutting-off knives, for finishing the ends of the hub, are on separate stands, below and in advance of the body and band knives. The cupping attachment is gibbed to the tail stake and provided with a gauge to regulate the depth of the cut. The shape of the knife governs the style of cup. A friction clutch turns the hub, the frictions being disengaged by a treadle.
The Automatic Hub and Finishing Machine shown in Fig. 3 is for the purpose of turning plain, beaded, banded. Sarveu, and Warren hubs complete, with unskilled labor.
The rough hub block is placed in the machine, which first roughs it down to the proper size by a roughing knife having a straight face 12 in. long, and which is fastened to a stand at the back end of the sliding carriage, with its cutting edge extending downward, taking off a ribbon about k in. thick of the full length of the hub at one cut, a gauge Ihniting the depth of cut. By a reverse movement of the hand wheel, the roughing portions retreat and the fin ishing knives come into play, the diameter to which they turn being regulated by screws at tached to the carriage, so that, once adjusted, the machine turns out hubs of only one finished diameter. The finishing knives are at the opposite side of the carriage from the roughing, and their cutting edges extend upward. At each end, upon the same stand as the finishing knives, are the knives for cutting band seats ; on separate stands, the knives :or finishing the ends : these last being in advance of the body and band knives. A single set of knives will
turn and finish hubs of the same shape to any diameter within the machine's capacity. The feed is by friction.
The hub-boring machine shown in Fig. 4, and made by the Defiance Machine Works, is for boring hub blocks up to 12 in. diameter and 13 in. long. The block may he inserted with the hard or soft part central with the boring bit, regardless of its external shape. The removal of this soft part keeps the block from checking when seasoning, and adds to the value of the prod uct. The carriage is gibbed to the frame, and slides to and from the bit by turning the hand wheel 80'. The jaws which receive the hub are mounted upon the sliding carriage, the boring tool travel ing, through the jaws. The jaw at the back part of the machine can be adjusted to receive hubs of various lengths, and is connected with the hinge joint. The upper end is fitted with a weighted eccentric lever to open and close the jaws. in operation, time end of the boring tool should extend slightly through the hole in the first jaw, the operator centering one end of the block by the boring tool, the other end being. set by the hole in the jaw at time back part of the machine : then the weight of the lever will hold 1 he block while being bored. The capacity is 200 blocks per hour.
The Heavy Hub-boring Machine shown in Fig. 5 receives the hub block between powerful universal jaws, which bold it central with the boring tool. In boring, the soft central part of the block is removed. By the use of solid steel reamers, the hole is bored in the block complete at one operation to the proper size, and tapered to fit the hub lathe mandrel upon which the block is to be turned and finished. The hub block is placed in and removed from the jaws when the carriage is moved to the back end of the machine. which is open, so that the material may be handled without lifting it over the frame. In operation the hub is clamped between the jaws, which are self-centering, and is presented to the action of the reamer by turning the large hand wheel shown.
Wheel-box Hething.—In cutting the seat for the box in a wheel hub there are two principal methods—in one of which the cutter remains at rest, the wheel turning at slow speed around the advancing but not rotating eutter-head ; in the other both the wheel and the cutter-bar turn. To turn a wagon or buggy wheel at high enough speed to do free cutting is impracticable by reason of the wheel not being in accurate balance for high speed, so that it would either fly apart or fly from the wheel chuck. The method of slow turn ing of the wheel about a non-rotating cutter is claimed by many to tear and splinter the wood, and so disturb the fiber as to shorten the life of the hub, as the spokes and box can not be given firm support in the disarranged fiber.