Electronics Forum | Tue Nov 05 18:17:00 EST 2002 | russ
This sounds like a contamination issue with the HASL finish.(solder on lead but not on pad). I have experienced this before and it was related to the HASL process at our supplier. They found some type of contaminate in the bath (unfortunately I can
Electronics Forum | Wed Nov 06 12:56:10 EST 2002 | slthomas
What I'm seeing is an occasional pattern of tear drop shaped features in a sea of nice shiny solder. The little islands don't really have any relief.....it's more of a surface finish feature than a 3-dimensional feature. The wetting angles are good,
Electronics Forum | Wed Nov 06 20:18:30 EST 2002 | davef
cvrgrrrl Your first thermal cycle with imm silver should be the easiest to solder. That you see copper indicates you did no soldering, got no wetting, produced no intermetallics, etc. Tell us again which components did not solder? Wuzzis "plug" t
Electronics Forum | Fri Nov 08 11:37:44 EST 2002 | jonfox
1. Back in the early days of consumer digital cell phones, we ran into the same problem. PCB with 2000 parts in a 5"x2" area, and double sided. We ended up using our standard vacuum tooling for the NIC side and stiff ESD safe foam for the NAC side
Electronics Forum | Mon Nov 25 07:58:27 EST 2002 | Yannick
Hi, I made a board wich I plated with immersion Tin, I tought it should be the same result as we had with tin lead but we ran into a weird problem. WE use a 63/37 no clean paste and on the Board with Immersion Tin the solder just make a ball ON
Electronics Forum | Fri Jan 24 17:05:17 EST 2003 | Hoss67
DDave, I do not have the benefit of having the old machine here for comparison unfortunately. Comparing topside wetting to old sample boards run on the older machine show similar results. No solder balls. I have a thermal profiler and have run ma
Electronics Forum | Fri Feb 28 08:57:34 EST 2003 | davef
We used to bake [100*C for 6 hours] all of our boards, but no longer bake at all. Before going off, your bake recipe is probaly OK. If anything, it's probably too short. Consider measuring the weight of wet boards, baking for a time, measure, bake
Electronics Forum | Tue Mar 04 18:38:12 EST 2003 | ruggi
Most of what we do (across 800+ varieties) is bottom side first. In general, there really aren't any problems as long as our Customers follow the .25g/cm wetted lead perimeter spec for weight (which many don't), and don't mount tall components on th
Electronics Forum | Thu Mar 06 11:36:37 EST 2003 | O' Connor
Hi, I'm experiencing a problem on a standard part made many times before -Ni/Au finish PCB, Reflow 100% SMD parts. After reflow the gold on the pads does not fully fuse with the solder paste it remains intact on the extremities of the pads, it seems
Electronics Forum | Thu Mar 06 11:50:22 EST 2003 | John O'Donnell
Greetings Sir, Although I am not qualified to address the issue in detail, I do know first hand that you can obtain very comprehensive and accurate solutions and explanations from George Westby, Director, Universal Instruments Advanced Technology and
