Electronics Forum | Fri Feb 03 13:15:44 EST 2006 | amol_kane
the flux in the solder paste should take care of the oxides. if possible print a board and run thru reflow to check for wetting issues......there are some published papers that say that the tarnish layer is too small to create any wetting issues or o
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 | Fri Oct 20 05:55:16 EDT 2006 | Eric Chen
40% in wetting problem. I would like to know any specific reflow profile in order to acheive good wetting at this type of lead. Besides, any specific paste e.g. halide containing paste required
Electronics Forum | Mon Apr 28 11:13:21 EDT 2008 | ck_the_flip
Here's a crude wettability test. Take a PCB - both types of finish - print them, and reflow with no components using your standard profile. Observe the wetting spread and flow of the solder paste. This rules in/out that it's PCB solderability.
Electronics Forum | Wed May 14 09:40:55 EDT 2008 | realchunks
Try running the second side first on a board. If it wets well, it points towards your board house. Run a blank board thru your oven and then try your normal process. If you see issues with the first side now - it definitely points towards your boa
Electronics Forum | Mon Jul 28 05:48:17 EDT 2008 | mattkehoe
What could be the main reasons for De-wetting in > reflow process. Can anybody answer Normally it is a contaminated surface finish.
Electronics Forum | Wed Jul 29 08:05:25 EDT 2009 | patrickbruneel
Deni, You also need to check if your flux is properly wetting the board. Flux dewetting on the surface can also cause webbing. You can check that with spraying flux on the board surface and watch the wetting behavior. Patrick
Electronics Forum | Wed Sep 15 20:59:23 EDT 2010 | genesan
hi All, Here i snap shot previous PCB(HASL) and current PCB(Immersion Silver).Base on the photo it could be PCB oxidize cause the non wetting?
Electronics Forum | Tue May 10 12:11:27 EDT 2011 | scottp
Do you have pictures and/or cross-sections of the non-wet? Is the HASL SnPb or SN100?
