Rotational Molding worked example

Pigment/Additive Usage at 98% dry-blend transfer efficiency: a worked example

Push dry-blend transfer efficiency up to 98% and the picture changes. This example computes every intermediate figure at that operating point. Use it when pigment/additive usage in rotational molding needs a buy quantity for the next rotational molding run and you do not want to short the line.

The inputs for this scenario

  • Total part surface area or shot weight covered: 500 units (unchanged)
  • Pigment/additive loading per unit of resin: 0.08 units (unchanged)
  • Dry-blend transfer efficiency: 98 % (raised for this scenario; the documented default is 85)

Working through the calculation

  • Applying the documented formula (Required pigment/additive usage = covered amount × use per unit ÷ transfer efficiency) to the inputs above produces each figure below.
  • At this operating point the engine returns 40.82 units for required quantity, the number this scenario is built around.
  • At this operating point the engine returns 40 units for theoretical amount.
  • At this operating point the engine returns 0.82 units for loss allowance.
  • At this operating point the engine returns 98 % for efficiency.

How this compares with the baseline

  • Against the tool's baseline example, where dry-blend transfer efficiency sits at 85% and the headline result is 47.06 units, this scenario comes in 13.27% below the baseline at 40.82 units.
  • It computes the actual pigment or additive weight you must charge per batch after accounting for transfer efficiency, plus the loss allowance over the theoretical amount. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Required quantity: 40.82 units (headline result)
  • Theoretical amount: 40 units
  • Loss allowance: 0.82 units
  • Efficiency: 98 %

Run it with your numbers

  • Every input above is editable in the live Pigment/Additive Usage calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.