CNC Machining worked example

Scrap From Machining with scrapped machined parts of 7 parts: a worked example

This worked example runs the scrap from machining numbers for a tougher week than the baseline: scrapped machined parts of 7 parts instead of the typical 14 parts. Estimate the cost of scrapped machined parts from scrap quantity, part cost, fixed investigation cost, and rework or disposition burden.

The inputs for this scenario

  • scrapped machined parts: 7 parts (the input this scenario stresses; the baseline uses 14)
  • cost per scrapped part: 86 $ / part (held at the documented default)
  • containment and investigation cost: 350 $ (held at the documented default)
  • rework, remake, and disposal burden: 420 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Total machining scrap cost = scrapped machined parts × cost per scrapped part + containment and investigation cost + rework, remake, and disposal burden.
  • total machining scrap cost works out to 1,372 $ at these inputs, and this is the headline figure for the scenario.
  • scrap cost per scrapped part works out to 196 $ / piece at these inputs.
  • scrapped part value works out to 602 $ at these inputs.
  • containment, rework, and disposal adders works out to 770 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where scrapped machined parts sits at 14 parts and the headline result is 1,974 $, this scenario comes in 30.5% below the baseline at 1,372 $.
  • Use it after a scrap event or at month-end to put a dollar figure on rejected CNC work and to compare the cost of scrap against the cost of prevention. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • total machining scrap cost: 1,372 $ (headline result)
  • scrap cost per scrapped part: 196 $ / piece
  • scrapped part value: 602 $
  • containment, rework, and disposal adders: 770 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Scrap From Machining calculator, set scrapped machined parts to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.