Fig. 668.
Fig. 669.
Another example is that of making a table, bench, chair, horse, or any four-legged object stand evenly. If it stands on three legs, which is a common fault and likely to occur in your first attempts, do not hastily saw one leg shorter by guess, and, making it too short, saw another and so on until it stands firmly, when the top will probably be all out of level. If there is any true surface on which you can stand the article (right side up), you can level the top by wedging under the legs until the corners of the top are equally distant from the surface on which the object stands. Then setting the compasses at a distance equal to that at which the end of the shortest leg is raised (Fig. 668), scribe around the other legs, which can then be cut off.[50]
See also Winding-Sticks and Marking.
Setting Saws.—See Sharpening.
Sharpening.—Before attempting to sharpen your tools yourself it would be well to read the advice given on page 22 under Care of Tools.
The general process of sharpening edged tools is first to grind them to as keen an edge as possible on the grindstone, or the emery-wheel, then to smooth down the coarse edge left by the grindstone by rubbing on a fine stone with oil or water, and finally stropping on leather. The grindstone must be kept wet while grinding or the heat caused by the friction of the tool on the dry stone will ruin the temper of the steel. Besides, the water carries off the waste particles of stone and steel. Stand on the side towards which the top of the stone turns. The tool can be ground with the stone turning from you, and, in fact, this usually seems the natural way to a novice, but it is usually more difficult to grind uniformly in that way and too thin an edge (a "wire-edge," ragged but not sharp) is apt to be produced, the removal of which is difficult without further damaging the edge and delaying the final sharpening.
To grind the point of a knife, it can be moved back and forth lengthways with a curving motion, while resting flat on the grindstone, and to grind the straight part of the blade, it can be allowed to bear very slightly harder near the edge of the stone than elsewhere, as it is passed back and forth.
To grind a chisel, grasp the handle with the right hand, hold the blade in the left hand with the fingers uppermost and near the cutting-edge. The arms and wrists should be kept as rigid as possible, the former at the sides of the body, so that the tool may be held firmly against the motion of the stone. Lay the chisel with slight pressure quite flatly on the stone and then raise the handle until the bevel touches the stone. As you grind keep moving the tool slowly back and forth across the stone, which helps keep the edge of the tool straight and prevents the stone being worn away too much in one place. Use plenty of water.