We do that same thing with our J-STD-001 students. L, M, H, what does the flux do to copper? J-STD-004. I saw a WS flux with a caution on the label stating that cleaning should be initiated immediately after the soldering process, as "greening" of the board may begin as the board cools. Ouch. > -----Original Message----- > From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory > Sent: Wednesday, May 05, 2004 1:40 PM > To: [log in to unmask] > Subject: Re: [TN] Green residue. > > I did an experiment this morning. I put a couple of drops of > flux on a penny about three hours ago, and I just looked at > it...green as grass. It was Kester ZX-2331 WS > > -Steve Gregory- > > > > There was some soldermask touch up but not anywhere near > the parts in > > question. I am thinking that since the board was assembled > in one area > > and bagged to bring it in for cleaning that there might > have been some > > WS flux in the bag. That seems the most likely right now. > > > > -----Original Message----- > > From: Crepeau, Phil [mailto:[log in to unmask]] > > Sent: Wednesday, May 05, 2004 12:25 PM > > To: [log in to unmask] > > Subject: Re: [TN] Green residue. > > > > > > is there any chance there was solder mask touch up going on > in this area? > > --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------