In a message dated 11/26/1999 7:15:48 PM Pacific Standard Time, [log in to unmask] writes: > Mike, > the old mil spec. clearly indicated the difference between AR, UR, SR > coating and their usage...I am not sure if similar guideline exist for the > selection of conformal coat for commercial product...I don't think the > selection of any material based on "familiarity or irrational personal > preference" are the common practice...(hopefully, not)...jk The difference is clearly defined, however, the proper occasion for using one over the other is not. As a conformal coating job shop, we get calls daily from folks in the commercial sector asking what the differences are and what would be the best to use. It is from experience that I say that familiarity and irrational personal preference often guide choice of coating. Even if not irrational, frequently, more than one type is specified for the same job (even in the government sectors) and the choice of which to use is governed by what has been used in the past or what is most readily available. Mike Moninger Thermospray ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################