Can a larger mold have a longer cycle?

Yes. Enter a supported proposed cycle time. The cost comparison allows that cycle to differ from the current mold.

What if there is no running-cost saving?

Break even stays blank because no positive running savings repay the added investment. Review the proposal or justify it using a different documented benefit.

Does the comparison include resin savings?

No. It assumes material and other per-part costs are unchanged. Add runner, scrap and material differences in a fuller investment comparison.

Should I round the break even quantity?

Round it up for a whole-part commitment. The displayed quantity is the exact economic threshold before whole-part rounding.

Tooling, Fixtures, Dies & Mold Economics calculator

Mold Cavitation Break Even Calculator

Compare molding running cost before and after a cavity increase. Enter both cavity counts, supported cycle times, one common machine rate and extra tool investment.

What this calculator does

Estimate the parts needed to recover added mold investment from cavity related running-cost savings.

Formula used

Current running cost per part = machine rate × current cycle seconds ÷ (3,600 × current cavities)
Proposed running cost per part = machine rate × proposed cycle seconds ÷ (3,600 × proposed cavities)
Savings per part = current running cost − proposed running cost
Break even parts = extra tool investment ÷ positive savings per part
Gross running parts per hour = 3,600 × cavities ÷ cycle seconds

Inputs explained

Current Active Cavities: Producing identical parts per shot on the current mold.
Proposed Active Cavities: Producing identical parts per shot on the proposed mold.
Current Running Cycle Time: Measured stable cycle time for the current mold and required part quality.
Proposed Running Cycle Time: Qualified or supplier supported cycle time for the proposed mold.
Common Loaded Machine Rate: Same applicable running machine and labor cost rate for both alternatives.
Additional Tool Investment: Extra qualified mold investment required for the proposed cavity count.

How to use the result

Best suited to cavity increase Proposal, mold investment screening.
Different machine rates, scrap, maintenance or runner costs require a fuller comparison. Demand, financing and available press capacity are outside this estimate.

Current U.S. benchmarks

The producer price index for plastic resins and materials stands at 280.569 (BLS, Aug 2026), up 6.6% from a year earlier. Quotes priced off last quarter's material cost miss this move.
The U.S. has 14,378 furniture and related products establishments employing about 355,594 workers (Census County Business Patterns, 2023).

Common questions

Can a larger mold have a longer cycle? Yes. Enter a supported proposed cycle time. The cost comparison allows that cycle to differ from the current mold.
What if there is no running-cost saving? Break even stays blank because no positive running savings repay the added investment. Review the proposal or justify it using a different documented benefit.
Does the comparison include resin savings? No. It assumes material and other per-part costs are unchanged. Add runner, scrap and material differences in a fuller investment comparison.
Should I round the break even quantity? Round it up for a whole-part commitment. The displayed quantity is the exact economic threshold before whole-part rounding.

Last reviewed 2026-10-06.