- Fibre length: 0.25–0.35 mm
- Yields lightweight, hard filling compouds
- For epoxy, polyester, and vinyl ester resins
Milled carbon is made from recycled fibres. The carbon fibres used therefore are equipped largely with PU-sizing. Most of the sizing evaporates due heat generated at the milling process though. When dry the milled fibres form fibre balls, which dissolve and spread out evenly in resin.