Maybe your boards are lactose intolerant? Do you have to go lead-free? Thankfully we do not. Bob Sent from my iPhone On Oct 10, 2013, at 5:21 PM, Ed Popielarski <[log in to unmask]> wrote: > Bivar uses lactose and sodium chloride. So now the question is "should we cry over burnt milk"? > > Ed Popielarski > Engineering Manager > > > 970 NE 21st Ct. > Oak Harbor, Wa. 98277 > > Ph: 360-675-1322 > Fx: 206-624-0965 > Cl: 949-581-6601 > > https://maps.google.com/maps/myplaces?hl=en&ll=48.315753,-122.643578&spn=0.011188,0.033023&ctz=420&t=m&z=16&iwloc=A > > > -----Original Message----- > From: Steve Gregory [mailto:[log in to unmask]] > Sent: Thursday, October 10, 2013 2:19 PM > To: [log in to unmask]; Ed Popielarski > Subject: RE: [TN] Charred dissopad residue > > Hey Ed, > > Haven't run across that problem (yet), and don't really know how to clean that. But I did run across another brand of spacers that I didn't know about before that's made of different material than what Bivar dissolvable spacers are made of...aren't bivar spacers made of some sort of sugar ? > > http://www.multi-seals.com/washawayspacers.php > > They're made of something called Polyvinylpyrrolidone, and contain no ionizable material, salts, sugars, metals, or soaps, and they are non-corrosive, non-conductive, and non-toxic. > > I just found them in a search today. I'm getting a sample pack of them sent to me check them out myself, you might check them out too if you've never tried them. > > Steve > > -----Original Message----- > From: TechNet [mailto:[log in to unmask]] On Behalf Of Ed Popielarski > Sent: Thursday, October 10, 2013 2:31 PM > To: [log in to unmask] > Subject: [TN] Charred dissopad residue > > Hi all, > > Had an odd problem today. > > We have built many of these assemblies with tin/lead solder but just now switched to lead free solder (higher temperature). > > The "Dissopad" contacting the PCB (at a via) liquefied, spread and charred. The residue is very difficult to remove, especially a concern since it is under components and could be "conductive". (pix available on request) > > We tried cleaning this with isopropyl alcohol and it didn't seem to dissolve the charred residue at all. > > I soaked one PCB in 140F DI water for 30 min. and re-cleaned in the aqueous cleaner. It did seem to remove the heavier residue, but there remains a film and smaller clumps on the board surface. > > Any suggestions would be appreciated! > > > Ed Popielarski > Engineering Manager > > [Description: FullLogo] > 970 NE 21st Ct. > Oak Harbor, Wa. 98277 > > Ph: 360-675-1322 > Fx: 206-624-0965 > Cl: 949-581-6601 > > https://maps.google.com/maps/myplaces?hl=en&ll=48.315753,-122.643578&spn > =0.011188,0.033023&ctz=420&t=m&z=16&iwloc=A > > > ______________________________________________________________________ > This email has been scanned by the Symantec Email Security.cloud service. > For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ > > ______________________________________________________________________ > This email has been scanned by the Symantec Email Security.cloud service. > For more information please contact helpdesk at x2960 or [log in to unmask] > ______________________________________________________________________ > ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________