I've noticed my prepreg isn't sticking to the mould as well as it did when it was new. Does that mean it's gone off?
Not necessarily, though reduced tack can be a sign that the resin has started to advance, either through storage conditions or accumulated out-life. If the prepreg has been stored correctly and is still within its stated out-life, it may well be fine to use. Lower tack can make lay-up harder, particularly on complex moulds. For structural components it is always worth checking the storage history before you carry on.
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