Electronics Forum | Thu May 07 20:28:35 EDT 2009 | davef
From our notes, the following is a series of snips from: "Copper Dissolution in Tin" LJ Turbini, PhD, adjunct faculty member, University of Toronto, Materials Science and Engineering, SMT 2/07 As the solder becomes molten, copper from the board diff
Electronics Forum | Tue Nov 01 14:46:31 EDT 2011 | davef
Agilent TestJet Technology White Paper In the early 1990s, the testing of digital parts became problematical. Previous in-circuit test techniques sought to ensure a correct, functioning part by applying digital patterns, called vectors, to the input
Electronics Forum | Fri May 15 21:39:48 EDT 2015 | jlawson
Reflow.. 1.Rehm (Germany) - Best in Class Best overall process stability heating system ( Alot of makers have started to copy there VX heating arrangement ). COnveyor chains can be a bit more attention in terms of maintenance on rehm , but if foll
Electronics Forum | Wed Jan 06 10:25:15 EST 2016 | swag
I've done more if this that you can possibly imagine. I've designed 100 or more router fixture plates. It's not always easy that's for sure. We use a Cencorp router. It does O.K. but definately a little tricky to get nice cuts in the flex only ar
Electronics Forum | Thu Feb 10 10:28:56 EST 2000 | Russ
Okay, Okay, here is the rest of the story! These boards were definitely plated, reworked to HASL, The component that is the most succeptable is a 160 pin QFP .5mm pitch. This component has nickel/iron lead frame. Significantly reduced apertures (1
Electronics Forum | Wed Dec 20 21:01:12 EST 2000 | Dave F
Talk about glam jobs � About once a month, we�d go over to the slaughter yard to get cows� teeth for Dr. Mueller. Then we�d fixture them on their side and run them in a machine that scrubbed them with a brush for weeks. The cool thing about cows te
Electronics Forum | Thu Oct 26 08:59:56 EDT 2000 | Antonio A. Medina
Ok guys, I need help. Here's the deal. We're getting micro solder balls under discreets on the bottomside of the board. Here's my set up... MPM screener w/vacuum plate 6 mil metal screen with 90% circular (rounded) apertures 7 mil (measured) past
Electronics Forum | Fri Sep 15 16:37:49 EDT 2000 | Dave F
Sounds like someone aimin� fo tha big hurt, if ya axes me. Two spots to place your lawn darts are: 1 J Hwang in "Modern Solder Technology � " states (p.354) that " � extreme CTE mismatch between silicon IC (~2) and the PCB (~16), solder connections
Electronics Forum | Thu Aug 31 18:59:55 EDT 2000 | Brian W.
Our customers use OSP, HASL, immersion tin and immersion gold as board finishes. If I recommend a finish to the customer, it is one of the immersion finishes or OSP. Those finishes have the advantage of a flat surface to deposit paste. HASL has va
Electronics Forum | Wed Aug 30 16:00:42 EDT 2000 | Dave F
Russells: You can mix the two solders you mentioned, assuming by "96s" you meant "96Sn / 4Pb". If you heat the two tin / lead alloys to a liquid state, you�ll form a tin / lead solution with properties different from either of the two solders. The
