As soon as an arbor-chuck is properly fixed, and a wheel slid thereon, all the adjustments for positions required previous to planing are completed excepting one. This adjustment consists in rotating the wheel on the pivot a short distance, in order to place the centre line of one of the intended teeth-gaps exactly right-angular to the table. In this position the wheel is to remain during planing; it is therefore next firmly fastened to the chuck, and is then ready for the cutting out.

A small wheel of a few inches in diameter can have its teeth entirely formed with the grooving tools of the planing-machine, without any preliminary drilling; but a wheel of six or eight inches in diameter, or any larger size, should be drilled previous to planing, a hole being made at the bottom of each intended gap. In some cases, two holes can be drilled for each gap, one hole being made at the extremities of the intended teeth. If such holes are carefully drilled to the scribed, line on the wheel's broad sides, the bottoms of all the gaps will, by drilling, be correctly shaped; such a half-round form being suitable for many classes of wheels; consequently, no subsequent shaping of the bottoms by planing is necessary. Such drilling also suits wheel-teeth of any form, because, whatever special shape may be intended, can be produced afterwards by planing, when drilling has been adopted for partly obtaining the required form Whenever it is convenient, drilling the gaps should be resorted to, because it is the quickest of all processes for removing metal in such places.

To commence the planing of a wheel which is not drilled, the vertical traverse of the slide-rest is adjusted to right-angles with the table, and a grooving tool having either a curved cutting edge or a straight one, is first used. The cutting edge must not be any longer than the desired distance between any two teeth at the bottom of the gap; although the edge may be, and usually is, rather shorter. This tool is advanced down to the bottom of every gap of the wheel previous to using any other tool. It is therefore necessary to loosen the fastening bolts, rotate the wheel a short distance, and again fix it, as many times as the number of gaps, the entire rotation of it being effected while the grooving tool remains as it was when first fixed in the clamps; unless it required taking out through being broken, or to be sharpened. By the time one rotation is completed, all the teeth-gaps are formed in the proper places, if the wheel were accurately adjusted by the centre line of each gap; but all the gaps are parallel, and are therefore of a shape which is different to that indicated by the lines on the broad sides. The shaping is consequently continued with other tools, and additional rotations of the wheel. When the work is well managed, and the tools good, two more rotations will suffice to complete the teeth ; a corner tool, and sometimes also a tool with concave edge for the curved broad sides, being used for each rotation. These final shaping operations for changing the original parallel shapes of the gaps when first made, must be done while the slide-rest, and consequently, the tool also, is inclined at a proper angle to the planing-table, in order that the advancements of the tool downwards may widen the mouth of each gap and produce the taper form intended.

There are two modes by which the tapering of the gaps may be executed. One of these requires the slide-rest to be inclined and fixed twice at one fixing of the wheel; and the other mode requires it to be inclined only once. If the rest is adjusted twice, the two sides of each gap are finished at one fixing of the wheel; but if the slide-rest is adjusted or inclined only once, only one side of the gap can be finished at one fixing. This mode being adopted, renders it necessary to gradually shift the wheel tooth by tooth, until a complete rotation is effected, during which every tooth is shaped on one side only, and while the slide-rest remains the whole time in one position. When one side of each tooth is thus treated, the wheel is entirely removed from the arbor-chuck and reversed, now placing to the flange that broad side of the wheel which was previously outwards. When reversed it is again fixed, and gradually rotated, to shape all those sides of the teeth that were not shaped during the previous rotation. At the shaping of the second lot of sides the slide-rest remains in the same inclined position it had before, because the wheel is adjusted each time by the centre line of each gap being put right-angular to the table, as directed. Generally speaking, it may be said, that all small wheels should be shaped by reversing the wheel side for side, and with only one fixing of the slide-rest; and that all large wheels which are troublesome to move about through deficient lifting apparatus, and other causes, should be shaped without reversing the broad sides, and with the rest adjusted in two positions inclined to the table, and also inclined towards each other.

Planing the teeth of a wheel which has been previously drilled at the bottom of each intended gap can be entirely executed with the slide-rest inclined in the two positions referred to, without requiring the downward traverse of the slide-rest in a vertical direction at any time during such shaping. While a wheel which is drilled is on the arbor-chuck and properly fixed with the centre line of a gap right-angular to the table, the oblique traverse of the rest will advance a tool down to the drilled hole with great facility, because it is not necessary to advance the tool-point to the bottom of the gap, this part being already shaped by the drilling. When one side of the gap has been formed with the oblique traverse of the rest in one position, the rest is next shifted and fixed for shaping the opposite side of the gap, being now inclined at the same angle as while shaping the first side, but now at the opposite side of the tooth-gap's centre line. It may by this be seen that the entire superfluous gap-portion can be removed by the two oblique traverses referred to, without any vertical traverse, as before stated. This mode of cutting out will be found a very easy means of forming the teeth-gaps of large wheels having wide gaps, because a wide gap will allow almost the entire gap-portion to be removed in one lump. This can be done by using a narrow grooving tool and advancing it down with the two oblique traverses; which of course will form the superfluous piece into a wedge-shaped lump, because the directions of the two traverses are inclined towards each other, the lump being completely detached as soon as the two narrow grooves made with the tool have extended to the drilled hole.

When the gap-piece has been removed, the roughly shaped sides are next carefully finished to the desired form; for which process tools having broad cutting edges are employed ; these, and also springy tools, should be used for this finishing, whenever the particular wheel in process possesses comparative great strength to sustain the strain imposed by the broad edges referred to. A careful finishing is always necessary, to avoid a subsequent filing.

It may be here stated that teeth-shaping by planing-machines much resembles that executed by shaping-machines, the el-chucks and arbor-chucks being used in about the same way for either class of machines; the only difference consisting in using shaping-machines for comparative small wheels, and using planing-machines for large ones.