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be done on milling machines can also be performed on the shaper with less expensive tools.
The planer, an example of which is shown at Fig. 30, B, is better adapted for handling large work than the shaper. In a planer the tool is fixed relative to the work, except as relates to vertical or lateral feeds. The tool is clamped in the tool post E, which is provided with an index fixture similar to that of the shaper and a hand feed lever for setting the depth of cut. The tool post carriage may be moved up or down on the supporting standards by means of a hand crank which operates the bevel-raising gears. The work to be machined is secured to the planer bed or platen B, which slides upon the ways machined in the bed A. As will be evident, the work is brought against a fixed cutting tool, whereas in the shaper the work is fixed and the cutting tool reciprocates over the work surface. A planer is useful in machining large objects such as motor crank cases, gear boxes and machining the flat surfaces on cylinder castings.
The drilling machinery provided should include a back-geared drill press having a table capacity to swing 24 inches. A typical machine of this nature of good design is shown at Fig. 31.. The tool should be back geared, meaning that the spindle speed may be slowed down for handling large drills or doing heavy work. It should have both hand and power feed and a table adjustable for both height and position. In the machine shown the table may be swung entirely clear or off to one side and large work supported directly on the base which is provided with slots capable of taking T-bolts. The spindle which holds the drills may be raised by a hand lever for quick feed, by a hand wheel acting through worm gearing for slow feed and by level gears for power feed. The spindle drive shaft is provided with a keyway and passes through the main drive bushing which is driven by bevel gears at the top of the column. A drill press may also be used for boring and will handle large work that cannot be conveniently supported in a lathe.
A large variety of milling work can also be done if a milling machine attachment such as shown at Fig. 32, A, is provided. This has a circular base about 12 inches in diameter and a table 161/2 inches long x 61/2 inches wide. A longitudinal feed of one
Fig. 31.—Medium Size Back Geared Upright Drilling Machine.
foot and a cross feed of 7 inches is provided by the fixture itself, which can, of course, be increased somewhat by swinging the drill table. The table of the attachment is provided with slots for three half-inch T-bolts for clamping work, and the vise jaws pro
vided have an opening of ten inches. The table is provided with an index support so the work may be set at any desired angle.
If possible it is well to provide a smaller drilling machine having hand feed only, which is known as the sensitive drill press. This should have three or four speeds and be capable of taking drills up
to at least three-eighths of an inch in diameter. The table should be adjustable up or down and sideways, the arm should swing to the right or left and should be of the type that permits one to put either a V-block or cup to support bar stock in its place. A light form of sensitive drill that is suitable for use on the work bench and which is electrically operated by a small motor is shown at Fig. 32, B. A variety of speeds is obtained owing to the friction drive. The starting rheostat and switch are mounted conveniently on a base permitting secure attachment to the bench.
Among the smaller appliances that are comparatively inexpensive and yet very useful may be mentioned the power hacksaw, which is not only simple but consumes very little power and is automatic in action after once being started. It occupies but little floor space and is very useful in cutting pieces from bar stock, such as steel, iron, or brass more than an inch in diameter. A typical power hacksaw is shown at Fig. 32, C. This consists of a frame, reciprocated by a crank, which imparts its motion to the saw frame through the medium of a connecting rod. The crank is turned by a pulley which is usually belted direct to a very small pulley on the line shaft and which turns at a speed considerably lower than that member. The feed is automatic and may be varied by altering the position of the weight regulating the amount of pressure with which the saw bears against the work. The piece to be cut is securely held in a vise attached to the bed of the machine which is supported on cast iron legs in order to raise it to a convenient height from the floor. A simple trip is provided, so that when the piece is sawed through, the drive will be interrupted and the saw frame will remain stationary.
An arbor press of large capacity is almost a necessity, and in even the smallest shops some kind of a press is essential for making force or press fits, removing parts forced on, straightening bent axles or tubular housings, and for removing arbors from parts machined on the lathes or millers. A press capable of exerting 10 to 15 tons pressure will be sufficient to cope with any work brought into the ordinary shop. One or two smaller arbor presses can be used to advantage and should be mounted directly at the ends of the large lathe beds, these serving to straighten small parts, such as valve stems, etc., and to do light work in making force fits, and in inserting and removing arbors from all work in which these are necessary.
A number of different designs of arbor presses are shown at Fig. 33. That at A, has a distance between screws of 20 inches and a distance between the head and table of 36 inches. Its capacity