Hi Wee Mei, To echo what others have already said. Your colleague can also check the manufacturer's coating thickness recommendation for a specific product. (I'm sure that's where IPC-A-610 got the numbers.) I strongly recommend staying within the acceptable range. My personal preference is to target slightly higher than the middle of the spec., if the range is broad enough. I've run into problems, on the processing side, when someone specified well above the max. and we had hideous solvent retention. Folks using conformal coating as a potting compound are not my friends. Hans ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Hans M. Hinners Electronics Engineer Warner Robins - Air Logistics Center (WR-ALC/LUGE) 226 Cochran Street Robins AFB GA 31098-1622 mailto:[log in to unmask] Com: (478) 926 - 5224 Fax: (478) 926 - 4911 DSN Prefix: 468 -----Original Message----- From: fullname [mailto:[log in to unmask]] Sent: Thursday, May 30, 2002 10:27 PM To: [log in to unmask] Subject: [TN] Coating thickness IPC-A-610C section 9.1.3 mentioned the following coating thickness : Type AR Acrylic resin 0.03 - 0.13mm Type ER Epoxy resin 0.03 - 0.13mm Type UR Urethane resin 0.03 - 0.13mm Type SR Silicon resin 0.05 - 0.21mm Type XY Paraxlyene resin 0.01 - 0.05mm Questions asked on behalf of my colleague are : 1. How does one arrive at the coating thickness for each types of coating material? 2. What is the impact to my board or components if my coating thickness exceed or below the range stated above? Regards - Wee Mei ---------------------------------------------------------------------------- ----- 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 e-mail to [log in to unmask]: SET Technet NOMAIL 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- 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 e-mail to [log in to unmask]: SET Technet NOMAIL 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------