Fig. 62.—Chisels.
A, tanged firmer chisel; B, socket
chisel; C, beveled-edge chisel; D,
mortise, or framing chisel.
(D.) Handles for paring chisels may be of any hard wood and of any convenient shape, as these should not be pounded upon. Although they are occasionally used for cutting small mortises, it is not a good practice unless the tops of the handles are protected by leather or fiber tops. Mortising chisels should have handles of the toughest wood obtainable, preferably hickory, with leather nailed with small brads upon the top to protect the wood. If a leather washer is fastened to the handle by a pin or dowel, the wood will in time pound down and the leather be broken out and destroyed, while if braided upon the handle, the leather may be renewed as often as necessary. An iron ring, or ferrule, is used by many to prevent the handle from splitting, but this will bruise the face of the mallet. A hammer should never be used upon any sort of wooden handle, or the handle will be very quickly destroyed, but a mallet will injure it comparatively little. In fitting the handle to the chisel blade, care should be used that they are in perfect alignment, as otherwise a sharp blow may break the blade.
(E.) In sharpening a mortise chisel, it should be ground at an angle of not less than 30°, as a thinner edge would be apt to break upon coming in contact with a knot. A paring chisel may be ground as thin as 20°, as it does not have to stand heavy blows, and a better edge for the purpose may thus be obtained. In whetting a chisel, the bevel must be carefully maintained, and the back kept perfectly straight, like the face of a plane iron, or it will be impossible to work to a line.
Fig. 63.—Drawshave.
47. Gouges may in general be described in the same way as chisels, except that they are curved instead of flat. The terms “inside” and “outside,” used in describing them, indicate whether they are ground upon the inside or the outside of the curve.
48. The drawshave (Fig. 63) is often used in cutting curves, in chamfering, and for roughing out work. The patent drawshave, with folding handles, is a safer tool to keep in the tool box, as the edge is protected, but it is not as satisfactory for general work as the ordinary rigid-handled tool. If the latter is used, a piece of wood should be fitted over the edge to protect both it and the hands when the tool is not in use.
Fig. 64.—Spokeshave.