Adam: Please see below... > What are the known etchants useful for boards made with electroplated tin > etch resists ? We have been using alkaline sulfate based etchant which works > very well, even with a 1 um bright tin plating thickness. Uh, Adam, you are probably using the best etchant known for Tin, and getting away with thinner Tin than anyone using any other etchant. The only other etchant suitable for use with Tin is a variant on what you are currently using, and it is based on ammonium chloride....and most people in the world use this one, and most people using this etchant need 5-6 um of Tin. Why do you want to change? Rudy Sedlak RD Chemical Company --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------