I agree. Even stripping a board completely there will always be some coating left between fine-pitch leads or under components. Normally, it is only stripped for repair. Then recoated with 1A33 again. Then again, I have customers tell me to apply 1B31 over parylene. Lloyd Duso Plant Manager Diamond-MT (814) 535-3505 www.Diamond-mt.com On Fri, Sep 14, 2018 at 10:24 AM Douglas Pauls < [log in to unmask]> wrote: > I don't know Chris, I would consider scrapping the assembly. 1A33 is a > pretty durable urethane. You can spot strip it OK, but stripping ALL the > coating off of an assembly is going to be pretty tough. As Les said, the > residues from the stripper can be harmful if not completely removed. > > Doug Pauls > Principal Materials and Process Engineer > Rockwell Collins > > > On Fri, Sep 14, 2018 at 9:19 AM Chris Thierolf <[log in to unmask]> > wrote: > > > Humiseal 1A33 UR was applied instead of SR. Vendor suggested removing > then > > re-applying SR conformal coating. If residue is a potential issue as you > > say then the Silicone will trap the residue on the PCB. This is a > problem. > > I will have to do 100% electrical testing to hopefully rule out this > > condition. > > > > -----Original Message----- > > From: TechNet <[log in to unmask]> On Behalf Of Bogert, Gerald L > (Contractor) > > Sent: Friday, September 14, 2018 9:27 AM > > To: [log in to unmask] > > Subject: [EXT] Re: [TN] Humiseal Stripper 1063 > > > > September 14, 2018 > > > > > > This chemical stripper gel product should only be used as a last resort > > for removing Type UR coating when other methods of removal such as grit > > blast or use of heat are not viable. If the gel is not completely > removed > > or neutralized by cleaning process, it will leave conductive residues > that > > can cause improper circuit card operation. > > > > > > ________________________________ > > From: TechNet <[log in to unmask]> on behalf of lduso - Diamond-MT.com < > > [log in to unmask]> > > Sent: Thursday, September 13, 2018 9:05 PM > > To: [log in to unmask] > > Subject: Re: [TN] Humiseal Stripper 1063 > > > > Yes and yes. I have used this many times to remove urethane coating from > > customers CCAs. It does work but can be dangerous. Success often depends > on > > the coating, the thickness, and how much of the board is uncoated. We try > > to use the most mild stripper that will get the job done sufficiently. > > > > Is complete removal necessary? > > > > On Thu, Sep 13, 2018, 19:57 Chris Thierolf <[log in to unmask]> > wrote: > > > > > Anyone use this on fully assembled PCBs to remove Urethane conformal > > > coating? Any risk to components? > > > > > > > > > Chris Thierolf > > > Principal Engineer, EE > > > > > > L3 Power Distribution - SPD Electrical Systems > > > 13500 Roosevelt Blvd. > > > Philadelphia, PA 19116 > > > Ph. 215-698-6390 > > > [log in to unmask]<mailto:[log in to unmask]> / > > > www.L3T.com<<http://www.L3T.com<> http://www.l3t.com/> > > > [cid:[log in to unmask]] > > > Confidentiality Notice > > > This Electronic mail transmission is confidential, may be privileged > > > and should be read or retained only by the intended recipient. If you > > > have received this transmission in error, please immediately notify > > > the sender and delete it from your system. > > > > > > > > > Beginning April 1, 2018, L3 Technologies, Inc. will discontinue the > > > use of all @L-3Com.com email addresses. To ensure delivery of your > > > messages to this recipient, please update your records to use > > [log in to unmask] > > > > > > > Beginning April 1, 2018, L3 Technologies, Inc. will discontinue the use > of > > all @L-3Com.com email addresses. To ensure delivery of your messages to > > this recipient, please update your records to use [log in to unmask] > > >