Bravo and Hip Hip Ol' Chap :-) KennyB _____ From: [log in to unmask] [mailto:[log in to unmask]] Sent: Thursday, March 04, 2010 2:17 PM To: TechNet E-Mail Forum; Ken Bloomquist Subject: Re: [TN] Conformal Coat Over No-Clean Flux No doubt, the Technet forum tis a great thing. I seem to recall us discussing this issue at length about a year or so ago. I suspect that if you search the archives, you would find the thread. Along the lines of what you ask. While Rockwell does use low residues fluxes (low residue is a flux, no-clean is a process) and we clean them, we also have a very successful "reduced clean" where we solder on parts that are either intolerant to our water wash process or it is "bloody inconvenient (I am feeling British this afternoon). We often conformallly coat over those residues, usually Alpha Telecore Plus or Kester 245 )both ROL0), successfully with Humiseal 1B31 acrylic or Humiseal 1H20AR1 acrylic-urethane. I know that you are looking at using urethanes, but don't use those very often. Anyone who knows Hillman or I know we test the crap out something before we ever allow it on product, so we looked at combinations of cored wire flux with additive fluxes, and the resultant combinations with the coatings, mostly the solvents in the coatings which would have a tendency to soak into the residues, potentially altering the chemical nature of the resulting mix. I think that you will largely find that solvent based coatings, such as one part urethanes or acrylics generally adhere pretty well to low solids flux residues, but again, depends on the flux. I can and does work, but like anything, ya gotta do the testing, test drive the car, kick the tires, etc. If'n ya knows what yur doin', life is great. If not, experience is an expensive educator, but often very thorough. Doug Pauls ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- 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 -----------------------------------------------------