Wood & Paper Manufacturing worked example

Roll Change Loss at 81% defective splice rate: a worked example

Push defective splice rate up to 81% and the picture changes. This example computes every intermediate figure at that operating point. A converting line lead uses it to size how much roll splicing erodes margin on a long production order.

The inputs for this scenario

  • Roll changes per production run: 12 changes (unchanged)
  • Cost per roll change: 140 $/change (unchanged)
  • Defective splice rate: 81 % (raised for this scenario; the documented default is 70)
  • Crew standby charge per run: 260 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Roll change loss = roll changes x cost per change x defective splice% + crew standby charge) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,621 $ for total roll change loss cost, the number this scenario is built around.
  • At this operating point the engine returns 135 $ / piece for roll change loss cost per unit.
  • At this operating point the engine returns 1,361 $ for variable roll change loss cost.
  • At this operating point the engine returns 260 $ for fixed roll change loss adder.

How this compares with the baseline

  • Against the tool's baseline example, where defective splice rate sits at 70% and the headline result is 1,436 $, this scenario comes in 12.87% above the baseline at 1,621 $.
  • It computes the total cost of roll changes in a run — defective-splice waste plus crew standby — and the average loss per roll change. 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

  • Total roll change loss cost: 1,621 $ (headline result)
  • Roll change loss cost per unit: 135 $ / piece
  • Variable roll change loss cost: 1,361 $
  • Fixed roll change loss adder: 260 $

Run it with your numbers

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

Last reviewed 2026-05-12.