Marine, Shipbuilding & Boat Manufacturing worked example

Fiberglass Hand Layup Resin Usage at 12% catalyzed resin waste allowance: a worked example

This scenario runs the fiberglass hand layup resin usage calculation on the strong side: 12% catalyzed resin waste allowance, with every other input held at its documented default. Use it when ordering polyester or vinylester resin for a hand layup job to ensure enough resin is on hand for the entire layup session without excess waste.

The inputs for this scenario

  • Total dry glass fiber weight: 80 kg (unchanged)
  • Resin-to-glass ratio: 1.8 ratio (unchanged)
  • Catalyzed resin waste allowance: 12 % (raised for this scenario; the documented default is 10)

Working through the calculation

  • Applying the documented formula (Net resin required = dry glass weight x resin-to-glass ratio) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,200 kg for total resin to order, the number this scenario is built around.
  • At this operating point the engine returns 144 kg for net resin required (no waste).
  • At this operating point the engine returns 1,056 kg for catalyzed resin waste.
  • At this operating point the engine returns 12 % for resin utilization rate.

How this compares with the baseline

  • Against the tool's baseline example, where catalyzed resin waste allowance sits at 10% and the headline result is 1,440 kg, this scenario comes in 16.67% below the baseline at 1,200 kg.
  • Use it when planning a hand layup or estimating resin drums for a hull, deck, or large molded part before kitting glass and catalyst. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Total resin to order: 1,200 kg (headline result)
  • Net resin required (no waste): 144 kg
  • Catalyzed resin waste: 1,056 kg
  • Resin utilization rate: 12 %

Run it with your numbers

  • Every input above is editable in the live Fiberglass Hand Layup Resin Usage calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.