Basic lathe operations

(a) Facing

Machining the end of the job flat and perpendicular to its axis. The tool is fed from the outside inward (or from the centre outward) with the cross slide, with the carriage locked.

  chuck |=========|
        |  job    |<-- tool moves across

(b) Straight turning

Reducing the diameter of a cylindrical job. The tool moves parallel to the axis with the carriage feed. Roughing uses a large depth of cut and feed; finishing uses a small depth and feed with a fine nose radius.

  chuck ||====================|
        ||   job (rotating)   |
                     [tool]
              <----- feed parallel to the axis

(c) Parting off

Cutting a finished piece off the bar using a narrow, blade-type parting tool fed radially by the cross slide. The tool is set on the centre line and used with a low feed and coolant, with a short overhang and a rigid set-up to avoid chatter.

  chuck ||========|  |=====|
        ||  bar   |  | piece being cut off
                   ^
            parting tool fed radially

(d) Knurling

Producing a diamond (cross) or straight pattern on the surface for grip (handles, nuts). A knurling tool with two hardened rollers is pressed into the rotating job at low speed (about 1/3 of the turning speed) with oil. The metal is displaced, not cut, so the diameter increases slightly.

  chuck ||=#=#=#=#=#=#========|
        ||  job (knurled part) |
             (o)(o)  <- knurling rollers pressed in

(e) Boring

Enlarging an existing hole with a single-point boring bar held in the tool post. The job is rotated in a chuck and the tool feeds axially inside the hole. It gives accurate size and concentricity; the bar should be short and rigid.

  chuck ||==========|
        ||  ______  |
        || |    <===|===== boring bar (fed along the axis)
        || |______  |
        ||==========|

Other operations: drilling and reaming (through the tailstock), taper turning, thread cutting, grooving, chamfering.