chapter  7
30 Pages

Marking out

This is the basic marking-out tool. It consists of a handle with a sharp point. The pointed end is made from hardened steel so that it will stay sharp in use. Engineers’ scribers usually have one straight end and one hooked end, as shown in Fig. 7.1. It is essential that the scribing point is kept sharp. Scribing points should not be sharpened on a grinding machine. The heat generated by this process tends to soften the point of the scriber so that it soon becomes blunt. The scribing point should be kept needle sharp by the use of an oil stone (see Fig. 7.27).