Electronics Forum | Thu Oct 17 21:32:28 EDT 2002 | davef
Please help to clairify the problem. Are we talking: * A pre-reflow [placement] problem? * A post-reflow [solder wetting] problem? Is the wetting issue that you mention related to the board or to the component? Please give us a little more detail
Electronics Forum | Wed Oct 27 13:20:47 EDT 2004 | DavidB
We are producing boards with Alpha 591S RMA No-Clean paste and are coating after SMC with Dow silicone ( toluene solvent based) conformal coating. We have experienced several failures due to soft shorts ( electrochemical migration?) We have also obse
Electronics Forum | Tue May 09 14:49:57 EDT 2006 | Larry
Hey guys, Anybody having trouble with increased false contact issues in ICT after switching from lead to lead free? Our test guys keep trying to imply that the flux residues are a problem (we're using Alpha EF2202), but as the soldering process eng
Electronics Forum | Wed Oct 04 16:24:48 EDT 2006 | russ
try Alpha OM5100 this is a noclean paste that we use and have done the same thing you are now, reflowing pbfree with pb paste, we run to max temp of 230C with this paste and use a straight ramp with no soak profile is about 4 mins long from ambiant
Electronics Forum | Thu Dec 07 14:13:06 EST 2006 | russ
Seriously folks Kester has some major issues with their thickeners. Do not spend time fixing your process that is the same as it has been. As a post here stated, Alpha is going to Mexico, we will see probs form them here pretty soon as well. Kest
Electronics Forum | Thu Jan 17 17:54:22 EST 2008 | dman97
Stay far away from the WS619 paste. It is a nightmare to get a decent solder joint out of it. And dont get me started on voiding issues with this paste. We eventually started to use Indium 3.2 lead free "water wash" paste and this drastically reduced
Electronics Forum | Sun Sep 27 22:39:55 EDT 2009 | rajeshwara
The same issue i faced 2 yrs before , i sugest 1. Use stencil of 4 mils ( Take care of Aspect Ratio and Area Ratio ). 2. Use Solder Paste of Type 4.5 and Viscosity in between 1100 to 1300. ( Try Solder Paste of Cookson or Alpha metals : OM338 T45-L
Electronics Forum | Thu Aug 15 17:05:54 EDT 2013 | srgbarba
Hi, I'm using WS-820 by Alpha metals and works good, but you must take in consideration the humidity and temperature that you have in your facility, In the process that we're following we left the board printed during 2 hrs and works ok (no pop up ef
Electronics Forum | Thu Jan 08 15:03:40 EST 2004 | dwzeek
We have an ongoing problem with our QFP144 packages soldering. It has not received much attention until late due to some customer failures. Most of the failures would show up in ESS testing and be repaired. The failure rate is about 2 in 1000 parts f
Electronics Forum | Mon Aug 17 03:05:59 EDT 1998 | Bob Willis
| | Where can I find a spec to put on my fab drawing, to call out the cleanliness of the board, before I recieve it. These boards will require a tight spec after they are assembled, so I want to know that they are clean when I get them. Any suggestio
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