Composites, Fiberglass & Advanced Materials worked example

Fiber Ply Count at 65% layup cell uptime: a worked example

Suppose layup cell uptime falls to 65%. This page works the full calculation at that level so you can see exactly which result moves and by how much. Estimate usable ply count capacity for laminate schedules, kits, or tool builds.

The inputs for this scenario

  • Plies laid up per layup cycle: 18 plies / cycle (held at the documented default)
  • Scheduled layup cycles in the run: 40 cycles (held at the documented default)
  • Layup cell uptime: 65 % (the input this scenario stresses; the baseline uses 90)
  • Ply first-pass acceptance yield: 97 % (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Gross fiber ply count = plies completed per cycle × planned ply processing cycles.
  • good fiber ply count works out to 454 plies at these inputs, and this is the headline figure for the scenario.
  • gross fiber ply count works out to 720 plies at these inputs.
  • fiber ply count lost to downtime works out to 252 plies at these inputs.
  • fiber ply count lost to scrap or rework works out to 14.04 plies at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where layup cell uptime sits at 90% and the headline result is 629 plies, this scenario comes in 27.78% below the baseline at 454 plies.
  • It multiplies plies per cycle by scheduled cycles to get gross output, then derates that by layup uptime and first-pass yield to give the count of good, accepted plies. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • good fiber ply count: 454 plies (headline result)
  • gross fiber ply count: 720 plies
  • fiber ply count lost to downtime: 252 plies
  • fiber ply count lost to scrap or rework: 14.04 plies

Run it with your numbers

  • To rerun this with your own numbers, open the live Fiber Ply Count calculator, set layup cell uptime to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.