How do you calculate total impeller machining cost?

Multiply impellers by per-part cost by the full-machining share, then add fixed setup. For 120 impellers at $85 each with 100% full machining plus $1,800 setup, total is $12,000.

Why does the per-unit cost exceed the per-part machining rate?

Because fixed setup is spread across the lot. At $85 variable and $1,800 setup over 120 impellers, per-unit cost is $100 - the extra $15 is amortized fixturing. Larger batches shrink that adder.

What does 'share needing full machining' mean?

The percentage of the lot that gets the complete machining routine versus partial or as-cast finish. At 100% every impeller is fully machined; drop it to model lots where some parts only need light cleanup.

How do I lower per-impeller cost?

Raise batch size to dilute the fixed $1,800, reduce setup through standardized fixturing or family tooling, or lower variable cost with better cutting parameters and cast-to-near-net blanks.

Should balancing be included in this cost?

Only if your per-part cost figure already rolls in dynamic balancing time. If balancing runs as a separate operation, either add it into the per-part rate or track it as a distinct routing cost.

Total cost vs per-unit cost - which do I quote?

Quote total cost to the customer for the job and use per-unit cost internally for margin analysis and comparison against target costing. Both come from this calculator.

Water, Wastewater & Pump Systems Manufacturing calculator

Impeller machining cost Calculator

Impeller machining cost is the fully loaded cost to turn, bore, and balance a batch of pump impellers, combining variable per-part machining with fixed setup and fixturing. Cost estimators and CNC cell leads in pump manufacturing use it to quote castings-to-finished impeller jobs and to decide batch sizes that amortize fixturing. Because not every impeller in a lot needs the full machining routine, the calculator lets you weight variable cost by the share requiring full work. The result is a defensible total and a true per-impeller cost that includes the fixed setup you'd otherwise forget to allocate.

What this calculator does

Estimate impeller machining cost for water and wastewater pumps from batch size, per-part machining cost, the share needing full machining, and fixed setup adders.
a pump manufacturer needs to cost the machining of a batch of centrifugal impellers before releasing a job or quote
It computes total impeller machining cost as quantity times per-part cost times the full-machining share, plus a fixed setup cost, then divides back to a per-unit figure.

Formula used

Total machining cost = impellers to machine x machining cost per impeller x share needing full machining + fixed setup and fixturing cost
Machining cost per impeller = total machining cost / impellers to machine

Inputs explained

Impellers to machine:
Machining cost per impeller:
Share needing full machining:
Fixed setup and fixturing cost:

How to use the result

Use it when quoting an impeller machining job or choosing a batch size that spreads fixturing cost effectively.
A single blended per-part cost and one full-machining share can't capture wide alloy or diameter variation; segment the lot when parts differ materially in cut time.

Current U.S. benchmarks

The U.S. has 21,668 machinery manufacturing establishments employing about 1,086,146 workers (Census County Business Patterns, 2023).

Common questions

How do you calculate total impeller machining cost? Multiply impellers by per-part cost by the full-machining share, then add fixed setup. For 120 impellers at $85 each with 100% full machining plus $1,800 setup, total is $12,000.
Why does the per-unit cost exceed the per-part machining rate? Because fixed setup is spread across the lot. At $85 variable and $1,800 setup over 120 impellers, per-unit cost is $100 - the extra $15 is amortized fixturing. Larger batches shrink that adder.
What does 'share needing full machining' mean? The percentage of the lot that gets the complete machining routine versus partial or as-cast finish. At 100% every impeller is fully machined; drop it to model lots where some parts only need light cleanup.
How do I lower per-impeller cost? Raise batch size to dilute the fixed $1,800, reduce setup through standardized fixturing or family tooling, or lower variable cost with better cutting parameters and cast-to-near-net blanks.
Should balancing be included in this cost? Only if your per-part cost figure already rolls in dynamic balancing time. If balancing runs as a separate operation, either add it into the per-part rate or track it as a distinct routing cost.

Last reviewed 2026-05-12.