Mail*Link(r) SMTP FWD>Bubbles in Conformal Coating Hi David and Dave, David, Dave's response about residual surface contaminants is a good one, we had some problems with inadequate cleaning of some residues under/along side some components. The residues reacted with the epoxy conformal coating to form many bubbles between the component body and the surface of the printed board. Some of the bubbles were so numerous the bubbles were almost "froth-like". There were also many isolated bubbles on the surface of the printed board -- cleaning was totally inadequate. After we suitably "cleaned" subsequent printed board assemblies (that were assembled using the same process and people), all the bubble related problems went away. Ralph Hersey [log in to unmask] -------------------------------------- Date: 7/29/96 9:47 AM From: ddhillma Hi David: Could you be getting a turbulent flow/disruption in the Nordson nozzle? What about a contaminate on the PWA that is reacting with the postcoat to form bubbles? Dave Hillman Rockwell Collins [log in to unmask] ______________________________ Reply Separator _________________________________ Subject: Bubbles in Conformal Coating Author: [log in to unmask] at ccmgw1 Date: 7/26/96 11:52 AM Has anyone ever experienced a problem with bubbles in conformal coating when using an acrylic coating (CONAP 1171) applied with a Nordson Select Coat system? The bubbles appear instantly as the coating is applied. The result is a non-conforming defect per IPC-A-610 section 7.1.2. Thank you. David Bruni Manufacturing Engineer MSA Instrument Division (412) 776-8848 *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * *************************************************************************** ------------------ RFC822 Header Follows ------------------ Received: by quickmail.llnl.gov with SMTP;29 Jul 1996 09:45:03 -0700 Received: from ipc.org by simon.ipc.org via SMTP (940816.SGI.8.6.9/940406.SGI) id LAA24894; Mon, 29 Jul 1996 11:34:35 -0700 Resent-Date: Mon, 29 Jul 1996 11:34:35 -0700 Received: by ipc.org (Smail3.1.28.1 #2) id m0uksqK-0000TSC; Mon, 29 Jul 96 08:58 CDT Resent-Sender: [log in to unmask] Old-Return-Path: <[log in to unmask]> Date: Mon, 29 Jul 96 08:39:31 cst From: "ddhillma" <[log in to unmask]> Encoding: 38 Text Message-Id: <[log in to unmask]> To: [log in to unmask] Cc: [log in to unmask] Subject: Re: Bubbles in Conformal Coating Resent-Message-ID: <"scGoe3.0.E0O.nDC_n"@ipc> Resent-From: [log in to unmask] X-Mailing-List: <[log in to unmask]> archive/latest/5408 X-Loop: [log in to unmask] Precedence: list Resent-Sender: [log in to unmask] *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************