As an example of chipping and filing let it be required to chip and file to shape and to fit a knuckle joint (or a double and single eye, as it may more properly be termed), such as in [Fig. 2284]. The eye being marked out by lines, the first operation will be to remove the surplus metal around the edges by chipping, which should be done (with the pin in place, so that it may support the eye) before the joint faces are filed at all, and should be carried in a direction around the eye, as shown in [Fig. 2285], in which v is the vice jaw, e a lead clamp, c the cut, and d the chisel. By chipping in this direction two ends are served: first, the force of the chipping blows is less likely to bend the eye if it is a light one, and, secondly, the chipping will not break out the metal at the edge of the eye, which it would be apt to do if the chipping was carried across. This is shown in [Fig. 2286], where a chisel cut is supposed to have been carried across from a to b and a piece has broken out at b. If the width of the eye is too broad for one chisel cut, a cape chisel should be run around it, as in [Fig. 2287], a d showing the cutting, the flat chisel cuts b, c being taken separately afterwards.
Fig. 2286.
Fig. 2287.
In order to illustrate the filing clearly, it will be necessary to show more metal to be filed off than would be the case in practice, unless the eye were very small, in which case it would not pay to chip.
