Phil, have you ever seen electronics from the war places like Iraq and Agfanistan? I got the task to create a cleaning procedure to save hundreds of advanced boards which were so contaminated with sand, that you could just see the contours of the components! They were 1B31 coated. First, I poured desert sand on fresh boards and put them in a +60 Centigrade oven for a week. As I suspected, the sand particles adhered more and more to the softened coating. It seemed impossible to remove them. But I found, that a suitable tenside added to ordinary tap water loosened the particles that were on their way to be imbedded in the coating. So, we simply used a popular cleaner that is used in many kitchens, used warm water and a brush, and could wipe off 95% of the sand with a gentle brushing. Sometimes you are lucky with very simple methods. Your combination of graphite and brass dust is really a bad situation, worst case, as I can see, but my home made method may be worth trying. The brushes we used were ESD safe, may not be necessary, but I insisted to buy such. The choice of brush depends on what you got on the boards. http://www.gordonbrush.com/esd/di_900.htm Inge ----- Original Message ----- From: "Phil Nutting" <[log in to unmask]> To: <[log in to unmask]> Sent: Tuesday, July 22, 2008 8:18 AM Subject: [TN] Washing dirty conformally coated boards Good morning, We have some circuit boards that we coat with Chemtronics Konform AR, that when returned from the field need to be washed to remove the graphite/carbon and brass dust (it won't blow off). Washing and rinsing at temperature tends to peel the conformal coating off. The currently process is hand washing and rinsing, but it is a totally uncontrolled process. I'm looking for recommendations for a more controlled process that is less likely to remove the coating. I just want to get the dusty stuff off the board. It looks I'm going to have to create a machine or controlled process the works at room temperature. Phil Note: All the information contained in this e-mail and its attachments is proprietary to Kaiser Systems, Inc. and it may not be reproduced without the prior written permission of sender. If you have received this email in error, please immediately return it to sender and delete the copy you received. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 -----------------------------------------------------