Regarding pores in Au-platings for cardege contacts David My name is Per Carlsson and working at the Swedish Institute for Production Engineering Research. I have worked with a project there we evaluated the Commercially available Gold-Plated Printed Circuit Boards. In this project we analyzed porosity and correlate it with the solderability. To our surprise we did not found any correlation. In your case you asked about porosity on card edge contacts and I don?t think there is any straight answer on this question. I suppose that it is thicker electrodeposited gold you talk about and your demand on the gold is that it should give you a good electrical contact and a good corrosion protection. If this is your requirement it is really a question about the environmental load your equipment will experience during service life. If the environment is corrosive, pores in the gold layer will lead to oxidation of the nickel and it could result in contact failure. In this case will the acceptance limits be very low. If you are interested in this matter there is a little handbook about corrosion of electronics that could give you more information. "Corrosion of Electronics" Published by The Swedish Corrosion Institute Bulletine 102. (Fax +46 8 16 72 70). If you are interested in solderability of Gold-Plate PWBs, we start a project about this matter in December. Regards Per Carlsson IVF/EP e-mail: [log in to unmask] There are plating specifications and test methods for gold over nickel plating on printed circuit board edge connectors. Verifying plating thickness is straight forward but what pass/fail criteria are used in the industry for porosity of gold over nickel? How many pores per CM*CM are allowed? Any sources of information/specifications would be appreciated. ===================================================================== * David Hamilton Ph: 334-283-7377 * Manager of Electronics FAX: 334-283-7293 * Schlumberger Water Division Email: [log in to unmask] * Hwy 229 South * Tallassee, Al. 36078 =====================================================================