Definition
Scrap is a part rejected as unusable and discarded, rather than reworked or used as-is, representing a total loss of the material, machine time and labor already invested in it. A part becomes scrap when a nonconformance is judged unfixable, or when rework isn't cost-effective relative to remaking the part.
Why scrap cost includes everything invested up to the point of rejection, not just material
Scrap cost isn't just the material; it includes all the machine time, setup and labor already invested up to the point of rejection, which is why a nonconformance caught late in a routing is far more costly to scrap than one caught early.
Where scrap decisions happen
Not on the drawing; scrap is an outcome of a nonconformance decision during or after production, not something specified by the part's requirements.
Common mistakes
Underestimating scrap cost as just the raw material value, ignoring the machine time, setup and labor already invested that's also lost when a part is scrapped late in its routing.
Scrap cost isn't just the material; it includes all the machine time, setup and labor already invested up to the point of rejection, which is why a nonconformance caught late in a routing is far more costly to scrap than one caught early.
See how Blake reviews a partFrequently asked questions
Is scrap the same as rework?
No, scrap means the part is discarded as unusable; rework means correcting the nonconformance to bring the part into compliance.
Why is late-stage scrap more costly than early-stage scrap?
Because more machine time, setup and labor have already been invested by the time a part is scrapped later in its routing, all of which is lost.
Can a factory reduce scrap without changing the process?
In-process inspection that catches a nonconformance earlier in a routing can reduce the cost of the resulting scrap, even without eliminating the underlying issue.