Rotational Molding worked example

Demold Time at 12% sticking and cleanup allowance: a worked example

What does the result look like when sticking and cleanup allowance reaches 12%? The full calculation is worked below with real intermediate numbers. Use it when demold time in rotational molding is being added to next week's schedule and you need an honest hours estimate.

The inputs for this scenario

  • Parts to demold this batch: 120 units (unchanged)
  • Parts extracted per operator-hour: 12 units / hr (unchanged)
  • Sticking and cleanup allowance: 12 % (raised for this scenario; the documented default is 10)

Working through the calculation

  • Applying the documented formula (Base demold time time = required work รท processing rate) to the inputs above produces each figure below.
  • At this operating point the engine returns 11.2 hr for adjusted run time, the number this scenario is built around.
  • At this operating point the engine returns 10 hr for base run time.
  • At this operating point the engine returns 12 % for allowance applied.
  • At this operating point the engine returns 12 pieces / min for process rate.

How this compares with the baseline

  • Against the tool's baseline example, where sticking and cleanup allowance sits at 10% and the headline result is 11 hr, this scenario comes in 1.82% above the baseline at 11.2 hr.
  • A figure at this level is achievable when sticking and cleanup allowance is genuinely sustained, not just peaked for a shift. It treats every part as equally easy to release; in practice release-agent condition, mold wear, and part geometry cause wide part-to-part variation not captured by a single rate.

Results at a glance

  • Adjusted run time: 11.2 hr (headline result)
  • Base run time: 10 hr
  • Allowance applied: 12 %
  • Process rate: 12 pieces / min

Run it with your numbers

  • Every input above is editable in the live Demold Time calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.