Electronics Forum | Mon Mar 22 09:37:28 EST 2004 | ellis
After 2nd time reflow of double reflow, wrinkles solder joints found on SOIC and SOT components.(only happen on the components at the underside of pcb during reflow, top side components dont have this problem) is this due to the reflow process proble
Electronics Forum | Mon Mar 22 19:46:17 EST 2004 | pdeuel
The bottom side is going into reflow somewhare near melting point of solder. Reduce bottom side temprature. Get a good mole so ramp and soak tempratures can be checked on bolth sides of the PCB. The object is to keep bottom side parts from approching
Electronics Forum | Thu May 05 01:21:42 EDT 2011 | city4497s
Hi Davef The problem shows up on * random location including component pads * all PCB and different PCB supplier * different solder paste lot * both printing and dispensing process * all production shift * we have only 1 production line It black,
Electronics Forum | Tue Apr 27 08:14:59 EDT 2004 | iqbal
Is anybody doing BGA soldering water clean solder. If yes how you are ensure cleaness. We have boards with Four BGA and 2000 chip and ICs.We are processing with no clean solder but we are getting bad wetting so now we are planning to switch to water
Electronics Forum | Thu Oct 17 00:34:59 EDT 2019 | jani
Hi, We have solder reflow use with water soluble flux and Tin/lead process. There is special glass component which needs to mask during reflow soldering and wash flux+solder mask post soldering. The existing solder mask does washes off. But leaves
Electronics Forum | Thu May 05 08:14:45 EDT 2011 | kahrpr
Where black pad exists, it is not a common problem. When I read it is totally random I doubt that. You have defiantly something going on that is unique with the process. It is either your board manufacturer or your solder paste or your profile. It c
Electronics Forum | Tue May 03 21:14:19 EDT 2011 | davef
Can we talk some to better understand the scope and breadth of the problem? * From your picture, it looks as if the problem shows-up on some pads, but not others. Is this accurate? * Is this lot related? * Is this related to a few items from a lot? *
Electronics Forum | Fri Apr 29 14:16:16 EDT 2011 | ppcbs
Below is the long explanation. This defect is most commonly found with BGA components, but can arrise with all components. I see it happening more now with lead free boards that are being assembled with a no clean flux. Best short term remedy is t
Electronics Forum | Wed Oct 17 17:43:27 EDT 2001 | davef
2) Open time: A 15-minute queue between paste, place, and reflow SB fine, assuming humidity is not too great. 3) Wash temperature: Yes. A wash temperature of 130-140�F SB fine. 4) Reflowed board was left too long prior wash: Are you washing: * After
Electronics Forum | Thu Sep 15 22:00:17 EDT 2005 | LeeHoMa
hi Stephen, Thank for your comment! Yes! My people also share the same view that customer is asking something which is in more theoretical side. They want us to collect a lot of statistical data to prove our process. Anyway, customer is not only
