The basic tool cost equation
Consumable tooling is a direct cost of goods sold. To accurately quote a job, the cost of the cutter must be amortized across the number of good parts it can produce. The formula is simple division: total purchase price of the tool divided by the expected part yield.
Cost per part = Tool cost ÷ Expected tool life
Worked cost per part example
An $85 indexable insert is expected to last for a 400-part production run. Dividing $85 by 400 yields a consumable tool cost of $0.21 per part.
Tool cost$85.00
Life400 parts
Cost$0.21/part
$85.00 ÷ 400 = $0.21 per part
Before you quote the job based on this number
This calculation represents a theoretical ideal. When applying this figure to a quote, factor in shop reality.
- BREAKAGEUnexpected tool breakage ruins the average. Factor in a scrap or breakage percentage across long runs.
- REGRINDSIf a solid carbide tool can be reground, the total lifetime part count increases, but the regrind service cost must be added to the initial purchase price.
- INSERTSFor indexable tooling, calculate the cost per active edge and the parts per edge to get an accurate number, rather than the whole body cost.
- HOLDERSTool holders and collets are generally considered shop assets or capital equipment, not job-specific consumables, and are typically excluded from this specific per-part calculation.