toolposts

A toolpost is a mounting device on a lathe that holds one or more cutting tools and positions them for operations such as turning, facing, and threading. It sits on the tool slide, typically the cross slide or the compound rest, and provides a standardized interface for tool height, alignment, and quick changes. The toolpost is a key part of the lathe’s setup, as precise tool positioning directly affects workpiece accuracy.

Several common types are used in manual lathes. A four-way toolpost carries four tool holders arranged around a central post, allowing quick rotation to index a different tool without removing others. Quick-change toolposts (QC toolposts) use individual, pre-set tool holders that clamp in and out with minimal adjustment, enabling fast tool changes and repeatable tool height. There are also dual or multiple-tool arrangements on larger machines for increased versatility.

Operation involves aligning the tool tip with the spindle centerline and setting the tool’s height to the workpiece’s center. Tools are clamped securely in their holders, and, for the four-way type, rotation is used to select the active tool. The compound rest can be used to angle tools for specific cuts, with the toolpost serving as the mounting point.

Maintenance and safety considerations include keeping the toolpost clean and free of debris, inspecting for wear or looseness, and ensuring clamps and screws are properly tightened. Tool height should be checked after changes to maintain accuracy. While computer numerical control lathes use turret changers, toolposts remain common in manual lathes for their simplicity, cost, and reliability.