Please don't use that etchant. It is recommended for a big hunk of copper - but is not recommended for electroplated copper deposits such as are on printed wiring boards. The attack to the copper can and does mask the presence of cracks and other problems Hydrogen Peroxide/Ammonium Hydroxide is the etchant to be used on printed wiring boards for copper evaluations Susan Mansilla Robisan Laboratory ################################################################ 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 web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################