Facing is the operation of machining the ends of a piece of work to produce a flat surface square with the axis. This is also used to cut the work to the required length. The operation involves feeding the tool perpendicular to the axis of rotation of the work piece. A properly ground facing tool is mounted in a tool holder in the tool post. A regular turning tool may also be used for facing a large work piece. The cutting edge should be set at the same height as the centre of the work piece. The selection of hand-feed or power feed depends upon the length of the cut. The surface is finished to the size by giving usual roughing and finishing cuts. For roughing, the average value of the cross feed is from 0.3 to 0.7 mm per revolution and the depth of cut is from 2 to 5 mm. For finishing, the feed ranges from 0.1 to 0.3 mm per rev. and the depth of cut is from 0.7 to 1 mm.
- The process of making a flat surface on a lathe machine is called facing.
- The job is held on a faceplate or chuck and the tool is fed at right angles to the bed to obtain flat surfaces.
- To safely perform a facing operation at the end of the workpiece must be as close as possible to the jaws of the chuck.