In practical turning, it is constantly necessary to change the position of the tool, from cutting upon the surface, to that of cutting upon the cylinder or edge, and as constantly back again to that for the surface; the corresponding frequent change in the position of the rest is objectionable, and the position fig. 417, is therefore infrequent except for large surfaces or deep internal turning. Surface turning is also far more conveniently executed when the tool is under the guidance of the armrest, with the tee remaining parallel with the cylinder.

The armrest, fig. 420, is a smooth steel shaft, about seven to nine inches long by a quarter of an inch thick; the face is about half an inch wide at the handle, tapering to less than a quarter of an inch at the end, which is turned up square, fig. 421, to form a rectangular hook or stud. The handle is straight, and from thirteen to fifteen inches long. In use, the handle is held under the left upper arm close under the armpit, pressed against the side, the blade lying flat upon and overhanging the rest, hook uppermost. The turning tool held in the right hand with the thumb and finger stretched out along it in the usual manner, lies on the armrest, the forefinger just touching the hook, which catches the side of the tool. The left hand grasps the pedestal of the rest by the three lower fingers, with the thumb pressed on the surface of the blade of the tool, lying on that of the armrest, holding both together down upon the tee. The left forefinger is bent like the other fingers around the pedestal, but is held just free of it, and presses up, and supports the under side of that portion of the armrest blade that overhangs the tee; the position of the bent, second joint of the left forefinger under the armrest, being nearly and sometimes directly beneath the tool. The forefingers and thumbs of both hands, the, ends of the tool and of the armrest, are thus all arranged together in one compact group.

Fig. 420.

421.

The turning tool, although in contact with the hook, is held very nearly as before, cushioned between the inside of the right forefinger and the end of the left thumb; the armrest itself being supported on the tee by the grip of the left thumb, and the position of the handle under the left arm. The tee of the hand rest usually stands parallel with the cylinder and rather high, giving a sloping position to the armrest blade, which places the face of the tool about radial. The tool may be raised while cutting, by depressing the left shoulder or still more, by allowing the armrest handle to slightly drop, and then regripping it a little lower down the side. The cutting action is regulated by the independent lowering, and twisting of the handle of the tool upon the armrest, in the same manner as when it is upon the tee; and also by pressure from the hands, or by the weight of the body, pulling upon the handle of the armrest.

This method of supporting the tool may appear formidable in description, but it is very easily acquired, and is often indispensable to the wood and brass turner. The armrest moving together with the tool across the surface, or within a surface curve, these are more freely traversed than when the tool lies on the tee of the rest; while in most internal turning, in which the tool considerably overhangs the tee rest, its edge is far more thoroughly supported, and easily and exactly guided when under the control of the armrest.