Lathe dog

A lathe dog is a dog designed to be clamped on a work piece to allow it to be revolved by a lathe face-plate. Lathe dogs are generally provided in straight-tailed or bent-tailed form. Bent-tailed dogs are able to engage directly with a face-plate slot or a chuck jaw but can crowd work off centre. Straight-tailed dogs do not present the issue of crowding work off centre but require a driving stud to be mounted on the face-plate.
A carrier is most often used when "turning" between centers on a lathe, but it may be used on dividing heads or any similar situation. It is used in conjunction with a drive plate and drive pins: the plate is mounted directly on the machine spindle (as with a chuck) and the drive pin is attached to the plate. In use the carrier and workpiece are inserted between centers and the leg of the carrier rests against the drive pin.
Spindle speeds are reduced when working with carriers, due to the unbalanced nature of the setup. Care must also be taken by the operator when using carriers, as it is easy to get snagged on one.