Electronics Forum | Mon Dec 22 19:43:43 EST 2003 | Dean
I have seen this affect on Immersion Tin and OSP. 70 to 90 % of the solder wicks to the lead and forms a "single" homogenous solder mass. This even though the pad was 100 % covered with paste... Evaluated different solder paste...did find variatio
Electronics Forum | Tue Dec 23 19:27:01 EST 2003 | davef
A more active flux may help, but if the nickel underplate on the component body is corroded [and not soldering], if could require a VERY active flux. Just an off-the-wall thought, are you sure that your heat recipe activates the flux properly? Slow
Electronics Forum | Fri Jan 22 16:03:17 EST 2021 | SMTA-64387124
Does anyone see any issues in mixing SMD and NSMD pads within one BGA footprint. We have high current pads which we want to make SMD and the other signal pads to be NSMD
Electronics Forum | Fri Jan 29 16:17:13 EST 2021 | donnie15
The impact is low on larger pitches and pad sizes. as things get to the .4mm pitch the pad differences start affect your ball size and yields. The trace size going into the pads and the solder mask relief can cause some odd shaped pads with signif
Electronics Forum | Mon Sep 08 20:55:04 EDT 2008 | davef
Of the six pads in the picture, which are the two that are unacceptable?
Electronics Forum | Tue Feb 09 16:53:06 EST 2021 | SMTA-64387083
The size of the pad changes among the two. A solder mask defined pad will always be larger than a copper defined by your mask expansion setting. This will affect paste volume, if your standard paste aperture is designed for copper defined pads you m
Electronics Forum | Wed Jun 13 06:42:14 EDT 2012 | brettrenishaw
We have a problem with our Unleaded wave solder machine only randomly soldering some pads. I have looked at the flux level and that appears fine aswell as cheking the preheat and solder height in the bath. The probelm is not exclusive to one perticul
Electronics Forum | Wed Aug 09 09:29:09 EDT 2017 | edhare
I recommend examining the problem pads and a representative bare board using SEM/EDS to determine if the problem is related to a board solderability issue. I can support this type of analysis (www.semlab.com).
Electronics Forum | Wed Jun 13 16:51:26 EDT 2012 | davef
Sorry, but I don't have a quick and easy answer. Before jumping the 'black pad shark,' tell us more about your boards ... * Is the gold still on the pads after soldering? * Can you make the pads take solder using a soldering iron? * Does this happen
Electronics Forum | Mon Jun 05 17:37:51 EDT 2017 | stevezeva
Hi Zac, In looking at your photos, you may not be having a problem with your machine, but with the solderability of the PCB. I've zoomed in to an area that looks to me like the solder has de-wet from the pad. The leads appear like it almost has a fi
