Belgique : glass sets exothermically wheras carbon endothermically ?. It is the resin that cures and in most cases a simlar epoxy resin is used for Carbon fibre and glass fibre. As far as I know all epoxies require heat to cure and will generate exothermic heat as the cross linking process goes on ( in thick laminates care has to be taken with the heat up rate to avoid run away exothermic reaction ). Can you expand a bit on the statement.