In electroless copper plating ("full build"), there is the catalytic phase involving palladium, but then the autocatalytic phase takes over whereby copper plates to copper. It has been a while since I have been able to observe this type of plating directly, but I suspect surface area of the exposed materials is playing a role. If we assume that some copper metal will precipitate in the fibres, the autocatalytic activity will be invoked. ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################