blank
A piece of material roughly cut, forged, cast, etc. to the size and shape of the thing to be made, and ready for the finishing operations; (coining) the disc of metal before stamping.
blank: raw material shaped and ready for final processing
A blank is a component that has been formed to approximate final dimensions but lacks finishing work. In manufacturing, it sits between raw material and the completed part, having undergone primary shaping operations like forging, casting, stamping, or machining, but still requiring secondary operations to meet specification.
The term carries different weight across trades. In coining and medal production, a blank is the prepared disc or planchet before the die strike. In forging, it is the roughly shaped billet after the impression die work but before trimming and machining. In sheet metal work, blanks are the cut shapes ready for bending or drawing. In injection molding, the blank equivalent is the shot just ejected from the mold, needing gate removal and surface finishing.
Working with blanks requires understanding the stock allowance built in for finishing. A forged steel blank might carry 2 to 4 mm of excess metal per side as machining allowance. Casting blanks often include larger tolerances because the primary process is less precise. This extra material, called the finishing or machining allowance, gets removed in turning, grinding, or other secondary operations to reach print dimensions and surface finish requirements.
Common problems and process control
Blanks that are too small force machinists to chase tolerances impossible to hold; blanks too large waste material and machine time. Inconsistent blank geometry from the primary process cascades into secondary operations. Surface defects like scale, sand inclusions in castings, or die lines in forgings must be spotted early, as they cannot be fully removed if cutting allowance is already tight. This is why many manufacturers inspect blanks before sending them forward.
The blank represents a critical handoff point in production. Poor blanks from upstream create scrap downstream. Good blanks arrive at the finishing station with correct dimensions, clean surfaces, and uniform hardness or temper, allowing predictable cycle times and first-pass quality. This is why process capability at the blanking stage, whether forging, casting, stamping, or other primary operation, directly determines overall manufacturing cost and yield.