Stay away from the Sodium Napthalene if possible - very nasty stuff. As an alternative try a Sodium Ammonia etchant - I have seen several customers get good results on PTFE boards with it. Regards, Kevin R. Thomas Ph : 440-808-1022 Fax : 440-88-1022 ################################################################ 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 ################################################################