Electronics Forum | Thu Jul 31 15:41:23 EDT 2003 | davef
Q: Could any of you guys tell me what exactly is this greenish thing ? A: No, but is not copper oxide. Copper oxide is brown, the color of a penny [here in the US] or an untreated copper laminated trace on a board. Many copper salts are greenish in
Electronics Forum | Fri Sep 18 11:23:32 EDT 2009 | isd_jwendell
I know nothing about Xbox specific rework, but have a lot of experience with PCB repairs. "...maybe think its a bad idea now not knowing what im doing" Don't get discouraged, it's a learning process. If it was that easy everyone would be doing it.
Electronics Forum | Sun Oct 20 12:49:11 EDT 2002 | johnw
Dave, I've had a few intersting conversations with Dr Lee, now there's a guy who know's stuff, but as it turn's out even he doesn't have all the answers on why things void. Many of his papers point towards oxides or contamination on the ball, so age
Electronics Forum | Sat Oct 19 08:33:50 EDT 2002 | johnw
The whole thread seem's to have gone off track. Russ we've been doing a fairly big bit of work on the whole BGA voidign thing as we were so unhappy with the answer's that we were getting from around the industry, basically no one really kows all the
Electronics Forum | Thu May 05 09:17:58 EDT 2005 | jimmiem
I tried soldering to several of the black pads and was successful, the solder stuck with no hesitation. so i guess this is not truly "black pad"? would that be a correct statement? What causes this blackening that looks like oxidation under the mic
Electronics Forum | Thu May 05 16:02:43 EDT 2005 | russ
I don't believe that you are seeing black pad. I think you are seeing an oxidized pad from your statement that these pads take solder. I would guess that these will be fine. But I would re-tin all pads prior to attaching the BGA to make sure.
Electronics Forum | Thu May 05 17:15:46 EDT 2005 | russ
You got what I think someone has called a "cold melt". If you were to run your removal profile awhile longer you would not see this. Anyway, you don't have any issues as this is very common (at least in my experience). FYI I was thinking your oxid
Electronics Forum | Tue Feb 14 09:29:46 EST 2006 | pjc
�..... their material acts as a barrier to oxidation," is wrong Mr. N. The MS2 material "consumes" oxides therefore removing the oxides from the dross by chemical reaction and releases the pure alloy. It is not a barrier and does not mix into the sol
Electronics Forum | Wed Aug 19 03:33:45 EDT 2009 | rocko
Pay attention that sometimes the ultrasonic energy may damage ICs.
Electronics Forum | Mon Dec 20 21:01:12 EST 2004 | davef
Bare inconel is NOT ment to take solder, because * Nickel develops a tenacious oxide layer that is very difficult to remove since the nature of the oxide is very dense, coherent, etc. * Chromium is difficult to solder. * Iron is difficult to solder.
