Electronics Forum | Fri Oct 26 07:41:26 EDT 2007 | bbl
We recently changed to an Amtech no clean paste and flux that is washable. So far excellent results. Far superior to the water soluable paste we were using. Fewer solder balls, longer life in printer, boards can be left up to 5 days and still come
Electronics Forum | Wed Jun 18 08:51:34 EDT 2008 | ldavis
We actually found the opposite to be true. Boards processed in VP are much cleaner than those processed in our air-only convection oven. We tested 5 lead free solder pastes upon implementation and found that the type of paste does affect the number
Electronics Forum | Mon Aug 30 10:17:16 EDT 2010 | markgray
We currently use this devise in one of our designs with no issues. We are using a 3mil stencil and a 45% apperature reduction. It is virtually impossible to eliminate voids but they are in an acceptable range. Solder balls are caused on this componen
Electronics Forum | Wed Jul 04 12:18:14 EDT 2012 | davef
Phil is correct in his description of proper rework technique. Possible explanations of the reason for popping of your BGA are: * Thermal cycling of components cause them to flex on a different point in the cycle that the board possibly resulting in
Electronics Forum | Tue May 14 21:59:25 EDT 2013 | davef
SAC is a lead free solder alloy. At one time, Nippon Micrometal Corp. (NMC) [158-1, Sayamagahara, Iruma, 358-0032, Japan; +81.4.2934.6101 F+81.4.2934.5454 nmc-net.co.jp] called some of its alloys: LF35, LF45(SAC305), LF38(SAC105) and LF31(SAC405).
Electronics Forum | Fri Dec 20 06:12:17 EST 2013 | bandjwet
Jimmy: Make sure to look in and around the board to make sure you have captured all locations of solder balls/fines as they are commonly caused by the profile or print issues. If they are non-embedded and are a 610 defect based on the class of your
Electronics Forum | Mon Feb 10 14:34:56 EST 2014 | jigo91
Hi, I wanted to know how can we test our paste quality, as viscosity, temperature in which it is delivered to the SMT line and other variables that can affect our paste dispense or soldering. Our concerns are that paste quality may be causing solde
Electronics Forum | Mon Sep 19 21:35:54 EDT 2016 | shriram
Appreciate your suggestion. NSMD pads are used for this design, the anomalies we found are 1. the trace running between pads has a lesser solder mask height compared the other area of the pads. 2. the NSMD pads doesnot have a trench close to pad e
Electronics Forum | Fri Sep 30 10:37:35 EDT 2016 | ttheis
We sometimes have a misprint and we would never re-print on a board with paste on it already because it will surely get paste all over the bottom of your stencil and could smear between traces. If we do mispront we have to clean the paste off the boa
Electronics Forum | Fri Mar 20 13:00:14 EDT 2020 | dwl
I've done over printing for Pin in Past applications and you'd be surprised how much you can over print and still end up with an acceptable solder joint and no solder balls. As others pointed out, there are a lot of variables involved, so trial and