Y'all, Question engineer asked me today, how thick can polyurethane coating be applied? We apply three coatings with the following procedure: 1) dip 2) dry for 2-3 hours to eliminate most solvent vapors 3) bake for 4 hours @ 60 deg C 4) repeat until 3 coats. Third coat is also baked. Question to my able colleagues: Anybody know of any long-term problems with this method? Any test results? We need to do this to cover all sharp edges for electrical isolation during operation in potentially high moisture environment. Specifically, a housing that can fill with condensation before draining away, and we can't seal enclosure. Considered paralene, but it costs more to coat the board than to build it... TIA Roger M. Stoops, C.I.D., PCB Designer Trimble Engineering and Construction Division 5475 Kellenburger Rd. Dayton, OH 45424-1099 USA Ph: +01 937.233.8921 or +01 937.233.4574 ext 288 Fax: +01 937.233.7511 --------------------------------------------------------------------------------- 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 the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------