Tooling

This class covers cutting and machining tooling built to federal specification: twist drills, counterbores, and countersinks, along with the related hand and machine tooling grouped alongside them. As with the rest of the catalog, each tool is built to a spec number that fixes its dimensions, material, and, where applicable, its cutting geometry — so a tool called out on a shop drawing or maintenance procedure can be sourced from any manufacturer building to that same spec.

Identification runs the same path as every other class here: a spec number or part number resolves to an NSN, and the NSN’s federal record carries the tool’s technical characteristics — size, shank type, material — along with manufacturer cross-references, so a worn or missing tool can be identified and requoted from its existing designation rather than matched by measurement alone.

Tooling in this class supports shop-floor machining and maintenance work wherever a procedure or a drawing calls for a specific tool by spec rather than by brand — drilling, counterboring, and countersinking operations on parts built to the same precision standards as the hardware they’re used to install.

How is a twist drill size identified by NSN?

A twist drill’s NSN resolves to its federal record — diameter, shank type, and material — which confirms the exact size and construction independent of manufacturer. This is the reliable path for replacing a drill called out on a drawing or a tool crib listing by designation rather than by measuring a worn or damaged bit.

What’s the difference between a counterbore and a countersink?

A counterbore cuts a flat-bottomed, cylindrical recess so a fastener head (typically a socket-head or hex-head type) sits flush with or below the surface. A countersink cuts a conical recess so a flat-head fastener’s angled underside sits flush with the surface. The two are specified for different fastener head styles and are not interchangeable tools.