Electronics Forum | Thu Aug 29 06:48:01 EDT 2002 | yngwie
I have seen several Imm Ag pad on the assembled board which have a copper colorleaching through the silver plating This happened on the pad which was not deposited with paste during the assembly process. Don't know if it is a problem, but we only
Electronics Forum | Fri Jan 18 04:45:32 EST 2002 | wbu
Ianchan, baking as being part of pre-heating is obviously sensless cause the PCB will not maintain any of that heat till soldering. Common reason for prebaking PCB�s is getting the moisture out to prevent outgassing, warpage and maybe other defects.
Electronics Forum | Fri Feb 22 08:26:51 EST 2002 | davef
You are correct. The gold dissolves in the solder. The gold is meant to protect the nickel from oxidizing, so that you can solder to the nickel. Obviously that didn�t work as planned. Your background information is very sparse. Two things come
Electronics Forum | Fri May 03 18:10:17 EDT 2002 | stownsend
Okay, here goes another thread about gold plating. I have been using gold plated PCB's for about two years now, with mostly very good results. The main reason I started using gold in the first place was because it is flat, solder wets to it nicely,
Electronics Forum | Wed Jul 03 10:32:05 EDT 2002 | davef
First, we have talked about drying / baking / demoisturizing / whatevering bare board previously. Search the fine SMTnet Archives to get started on recipes. Second and more importantly, you gotta fix this delamination problem. If it is delaminatio
Electronics Forum | Tue Aug 13 12:22:03 EDT 2002 | dragonslayr
A bit of gray area for you. consider the application over the specmanship. Why are the stiffeners there in the first place? Is the rigidity requirement a high function i.e. very necessary due to potential shock and vibration , etc.? The soldering is
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 | Wed Oct 23 16:56:03 EDT 2002 | mikestringer
Hi Marc I too have been using a fully synthetic Motor oil on Heller reflow ovens for a number of years. In our case Mobil 1 5W-50. We have a field failure problem with some 1% resistors under conformal coating where sulphates are dissolving the si
Electronics Forum | Fri Nov 08 08:52:54 EST 2002 | dphilbrick
Juan There are many things that cause this and the first thing I would do is request quality records from your board fab facility on that particular lot. If they are unwilling to give them to you this is a good sign they had a processing problem. Th
Electronics Forum | Tue Apr 01 17:29:58 EST 2003 | davef
R1: So if I understand you right, it could be possible that gold dissolved, but the ball still didn't wet to the underlying nickel. D1: Correct. The gold dissolves into the solder first. The solder wets to the nickel second. If you nickel is corro
