Hi Rod, I'm not aware of any real test a normally-equipped PCB lab can run to measure or test for the removal of chromates. However, there are other ways to measure effectiveness of a chemical clean line that should indicate fairly well how successful your removal was. The simplest way is the old standby "water break" test. Chromate interference will cause water to "break" and you can assume there may well be chromates left (of course it could also indicate finger oils or other contaminates as well). Another way, and one you're most likely using now, is to closely monitor weight loss through the line. I'd imagine you're removing anywhere from 20 to 80 microinches. Chromates will be removed during normal chemical clean cycles that maintain a reasonable etch rate. You may want to use laminate samples as your coupons in order to get a handle specifically on its etch rate. You can also try using a black oxide dip following your chem-clean process (process only through the oxide pre-dip and oxide bath). This will point out resin spots or perhaps areas of excessive chromates. Odds are that this method will point more accurately towards resin spots or foil pin holes rather than chromates. Good luck Mark Mazzoli Eng. Mgr. Circuit Technologies, Inc. 3622 Clearview Pkwy. Atlanta, GA 30340 770-458-1700 [log in to unmask] ----- Original Message ----- From: Rod Semen <[log in to unmask]> To: <[log in to unmask]> Sent: Tuesday, September 21, 1999 2:53 PM Subject: [TN] Quick, Chromate Test > Does anybody know of a quick test to see if I am removing chromate > coating on laminate foil? I know about EDX, but I want to do this in > our lab. > > Thanks, > > Rod > > ______________________________________________________ > Get Your Private, Free Email at http://www.hotmail.com > > ############################################################## > TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional > information. > If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or > 847-509-9700 ext.5365 > ############################################################## ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################