Electronics Forum | Tue May 23 09:01:48 EDT 2006 | russ
Seems as though the problem is with PCB and not component? "Solder does not wet to pads, wets to component" What is your board finish? Russ
Electronics Forum | Mon Jul 29 18:59:08 EDT 2002 | davef
Stand-ups are a common problem with 0402. Search the fine SMTnet Archives to get started.
Electronics Forum | Wed Jul 31 17:35:16 EDT 2002 | davef
* Finally, when soldered by hand, do the problem pads take solder? Yes, the XRF analysis will be interesting.
Electronics Forum | Thu May 25 08:00:49 EDT 2006 | davef
The warmest spot you measure on the board is the bare laminate. It will be 10*C hotter than a solder connection.
Electronics Forum | Tue May 23 09:27:37 EDT 2006 | Steve
Sorry I misled you. The PCB pads are wetting, but there is no fillet being formed. After reflow, it looks as though no paste was put down on the pads; however the paste print is fine. All other components solder real nice, it's only the Pd-Ag parts t
Electronics Forum | Thu May 25 09:14:04 EDT 2006 | cobar
Print a number of pads of the 0603 on to a ceramic substrate. Then place the 0603 on the paste on the ceramic and refow. If the paste shows no wetting onto the component it will prove that there is a problem with the components solderability.
Electronics Forum | Tue Jul 30 17:47:50 EDT 2002 | davef
Dewetting: Solder does not adhere to lead or land, caused by: * Poor solderability of lands. * Poor solderability of leads. * Solder paste integrity. * Lead plating integrity. Need more information, please: * What is dewetting [ie, component, pad, e
Electronics Forum | Tue May 23 09:50:37 EDT 2006 | flipit
They work well in silver conductive epoxy in hybrid applications. They are very poor in no clean applications. They don't work that well in OA solder paste either. Used them once in OA paste and in a nitrogen. They looked just fine. Solder to Pd
Electronics Forum | Tue May 23 02:29:41 EDT 2006 | Loco
No suggestions, but we've also had problems with silver palladium. No wetting on reflow, when we tried handsoldering them, we could actually scrape off the whole finish and were left with a black unsolderable underground. It was just 1 reel, seems
Electronics Forum | Mon Jul 29 16:43:55 EDT 2002 | mcm4me
I have a customer with up to 8% scrap from one board supplier and 1% from another supplier for solder dewett and no wet over ENIG finish with mask defined pads. Initially I suspected mask residue on pads because of the no wets but I have come to find
winsouce.jpg)
