Electronics Forum | Thu Dec 07 12:18:28 EST 2006 | realchunks
It may be for a double sided reflow process. Yes, some people do put the BGA on first. I know this first hand.
Electronics Forum | Thu Dec 07 14:17:03 EST 2006 | russ
I would bet that it is a SMT adhesive used to ensure that the BGA does not move during a secoindary reflow prcess. this glue is easily removed with a soldering iron. Russ
Electronics Forum | Wed Dec 06 22:35:05 EST 2006 | davef
Questions are: * When you say, "corner of some board's BGA chips", is it on the top of the package or between the board and the bottom of the package? * If between the board and the bottom of the package, does it span the distance between the board a
Electronics Forum | Thu Jun 27 11:56:40 EDT 2019 | slthomas
It seems to me that it would be easier to manually apply a little bit of chipbonder on the edge of the part after the first reflow than to tape the part down. The epoxy would cure sufficiently before the second reflow to secure the part after the s
Electronics Forum | Tue Feb 04 08:20:18 EST 2003 | roertner
This rule is very conservative depending on the epoxy you use and the subsequent handling of the board prior to reflow. You should use lead to pad contact area. Also be sure to look at part height and clearance on your flowsolder machine.
Electronics Forum | Thu Jan 02 08:49:35 EST 2003 | larryk
We use the epoxy gold finger gloves. They are cheap and can be cut to length. We get them from; Stevens Products, Inc 973-672-2140
Electronics Forum | Fri Apr 02 12:40:59 EST 2004 | Ron Herbert
White residue can often be caused by overheating the flux. When this occurs the flux is polymerized, basically turning it into an epoxy. You can usually determine if this is the problem by taking a pencil eraser to it. If it comes off, you have overh
Electronics Forum | Tue Aug 09 10:02:07 EDT 2005 | davef
Td or Decomposition Temperature (the temperature that the epoxy actualy starts to break down) should be greater than 330*C for lead-free. Search the fine SMTnet Archives for more on Td.
Electronics Forum | Thu Apr 19 16:54:32 EDT 2007 | flipit
I don't suggest using Pd/Ag or Ag/Pd terminated components unless you are forced to use them. You often see a line of demarcation that suggests a poorly wetted solder joint. I have had bad experiences with Pd/Ag terminated capacitors. Even when so
Electronics Forum | Wed Apr 18 08:14:20 EDT 2007 | davef
Silver palladium termination * AgPd-terminated capacitors are designed for conductive adhesion. Reflow or wave soldering is not recommended. [EPCOS Multilayer ceramic capacitors, Soldering directions, October 2006] * CONDUCTIVE EPOXY BONDING. Epoxy c
