David Contrary to your view, we have a water based acrylic coating that has been tested successfully to 200 DegC - that's 392 Deg F. As to the original question, Jim, I am not sure that the coating will achieve what you might be looking for, because the coating is not a very good thermal insulator. So your components will need to be able to work at the elevated temp - and the coating, such as the one I mention, will certainly help. Regards Graham Naisbitt [log in to unmask] Concoat ANNOUNCE their acquisition of the former Multicore SPCID business. MUST II Solderability Testing Systems - CM Cleanliness Testing Systems - Auto-SIR Reliability Testing Systems - SoldaPro & NEW SoldaPro Wizard Thermal Profilers For more information please visit our new web site: www.concoatsystems.com <http://www.concoatsystems.com/> Concoat Limited Alasan House, Albany Park Camberley GU16 7PH - UK www.concoat.co.uk <http://www.concoat.co.uk/> Phone: +44 1276 691100 Fax: +44 1276 691227 Mobile: +44 79 6858 2121 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of David Douthit Sent: Wednesday, April 24, 2002 17:34 To: [log in to unmask] Subject: Re: [TN] TEMP EXTREME James, How about acrylic conformal coating? You are so far above the Tg of acrylics that the coating can "flow", melt, evaporate, or all the above! (Not to mention letting contaminants reach the surface!) David A. Douthit Manager LoCan LLC "Marsico, James" wrote: Hello Technet: I think I may have asked this question a while ago (or something similar) but couldn't find anything in the archives. I have a surface mount assembly that gets installed into a top assembly housing, with covers. The test guys want to subject this assembly to 125 degrees C for 112 hours. Assuming that all of the components are rated for this temperature, is there anything else that says this isn't a good idea? I'm thinking about the solder joints, maybe decreased reliability due to excessive grain growth? How about acrylic conformal coating? The PWB is polyimide, so this shouldn't be an issue. Anything else? Thanks again... Jim Marsico Senior Engineer Production Engineering EDO Electronics Systems Group [log in to unmask] <mailto:[log in to unmask]> 631-595-5879 ------------------------------------------------------------------------ --------- 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 ------------------------------------------------------------------------ ---------