For grinding Lithe, boring. and chasing tools, planer-hook tools, and slotting-splining tools, supplementary chucks are used and set to the angles given for corresponding straight tools. The periphery of the grinding-wheel is not at right angles to the flat surfaces of the wheel, but is formed so that in the section the grinding surfaces will form a V containing an angle of 00'. With this shape of stone a vertical surface perpendicular to the axis of the stone can be ground by moving horizontally the chuck with tool toward the center of the wheel ; then, without disturbing the tool or making any change whatever, a vertical surface at right angles to the former surface can be ground by moving the tool horizontally in a direction parallel to the axis of the wheel.
Lapping-Machine.—This is a grinding device consisting of a lead or other soft metal surface, on which emery or oil is used. The machine shown in Fig. 3 is made by the Pratt & Whitney Co., for grinding thin, flat pieces that can not well be clamped for milling without retaining their winding irregularities. With this machine it is claimed that an unskilled workman can grind a true surface at much less expense than milling would cost. The diameter of lap is 18 in.; weight of machine, 1,100 lbs.; speed of lap, 1,500 revolutions per min.
Brown & Sharpe's Universal Grind ing-lfachine,—This machine, shown in Fig, 4, is suit able for both straight and taper, internal and external grinding, and is used in the manufact ure of spindles and boxes, either hard or soft cutters, either straight or angular reamers, arbors, jewelers' rolls, and standard external and internal gauges. The sliding-table carries a swivel-table, which turns upon a center-pin. This provides for grinding tapers without throwing the head and foot stock spindles out of line. In order that the swivel-table may be set accurately, it is provided with an adjusting screw. A scale shows the taper both in degrees and in inches per foot. The table may be fed and reversed automatically or by hand. The cross-feed is operated by hand. The head-stock is attached to a base-plate bolted to the swivel-table, and turns upon a center-pin. Its circumference at the lower edge is graduated to degrees. The foot-stock spindle is adjusted by a lever, and there is a spring to accommo date the expansion of the work.
The machine will swing work between centers 12 in. diameter and 30 in. long. The swivel-table can be moved to either side of its central position to grind tapers from 0 to 2 in. per ft. For grinding work on the face-plate or chuck, the head-stock can be set at any angle within the whole circumference. Two tapers can be ground, either internal or external, with out changing any of the. settings. The work can be ground upon fixed centers, being driven by a pulley which revolves upon one of them, or the head-stock spindle can be revolved while the work is held in a chuck. Wheels are used from I in. to 12 in. diameter.
Brown (C. Sharpe's Critter and Reamer machine, shown in Fig. 5, is exten sively used for sharpening straight or taper, shell or shank reamers; and for grinding edge and bevel cutters of any angle; straddle and face mills, cotter and hollow mills, and straight or taper milling cutters, cut either straight or spiral, with holes or shanks. It can also be used for sharpening worm or thread tools. In operating the machine the work is moved on and off the wheel, there being no lateral movement of the wheel.
The Xewinan Emery Planer, made by the 'Penile Co., is shown in Fig. O. This machine is used especially for grinding dies, chilled castings, and steel, and also as a substitute for the ordinary planer.
The principal dimensions are as follows: Floor-space. 29 X 36 in. ; length of spin dle. 421 in. ; diameter of spindle in bear ings, 2 in.: diameter of spindle between flanges. 1 k in.; size of pulley on spindle.
x rif in.: throw of spindle. 91 in.; size of table, 111; X 10 in.: vertical movement. of table. 17 in.: horizontal movement of t able, 36 in. As a maximum this machine has taken a cut in. deep, and has taken over a surface of 100 sr]. in, in 11 min. and 9 sec. The ordinary cut is to W in.
The Tan lie is shown in one of several forms in Fig. 7. The surfacing-table is 24 x t.1 in.. and is adapted for wheels 14 x 3 in, With this machine many small jobs may be done which would ot herwise go to the planer. The leading dimensions are: Height from floor to cen ter of spindle, 37.4 in.: distance between wheels, 18 in.: floor-space, 22 X 20 in.; length of spindle. 2!) in. ; diameter of spin d le in hearings, 11. ; diameter of spindle between flanges, 1 in.
The Itensmore is shown in Fig. N. At A are the driving-pulleys. journaled between arms on a lower cross-piece, in which is also socketed the lower extremity f the elevating: screw R. On t he upper cross-hend is swiveled a yoke, to which is jonrnaled a shaft C, carrying pulleys D. These transmit mo tion from the driving-pulleys A to the pulley .6', on the emery-wheel shaft. The shaft C passes through a metallic bock F, which fits loosely upon it, and which is ground off to a point on its under side, to form a bearing for an adjusting screw. This block is also bored to receive the arm G. which supports the grinding-wheel. The arm 0 is movable in the block, and can be fastened in any desired position by the set screw X. 1 is a counterbalance for the wheel. J is a stock, secured in place as desired, by a set screw not shown, and sup ported from below by the hand-wheel, by which it can be elevated and depressed. The stock has ways for a saw-bar, or a carriage with clamps for the blade. The saw-disk, in ease a circu lar saw is to be gummed, is attached to the end A' of the saw-bar, and the latter is properly adjusted and fastened to the stock, in such position us to bring the saw-teeth properly under the emery-wheel. The stock is then adjusted so as to bring it to a proper height by means of the elevating screw, and the arm G is depressed in front until the wheel is in proper posi tion. The wheel is previously adjusted to the proper angle of the tooth by partially rotating the arm, in the block P. and securing it when the wheel is at suitable inclination. When the apparatus is to be used to guin a straight-edged saw, the blade is confined in a carriage, and the wheel is set in relation thereto, as already described. The saw is gradually carried for ward by the carriage as each tooth is gummed.
The Thuile Automatic Planer Knife-Grinder is shown in Fig. 9. In this machine the knife is ground with a straight bevel with no change until the wheel is worn out, or it can he modified to grind a concave bevel, or square edges.
Thr Thuile Car Brass-Grinder is shown in Fii4. W. The brass is clamped between the jaws of the ehnek by a cam-tool ion actuated by a 11;111,111.. The chuck tits into planed guides, and thus travois square with the nintiou of the wheel. The table is moved horizontally by the crank and eonnerbog-1,,d. mid also rises and talk on planed ways, being pressed up by springs. The hand-wheel gives vertical adjustment to the lied by means of a chain beneath the base of the machine.
Groover: see Gaining-Machines.
Grubber: see Pulverizers and Harrows.