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 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 Jul 30 08:37:39 EDT 2002 | davef
When you talk about 'poor wetting', 'dewett', 'no wets', etc.; are you seeing solder pulling back or away from the pad? Please describe the condition. Dewetting. The condition in the solder joint in which the liquid solder has not adhered intimate
Electronics Forum | Tue Feb 21 09:19:50 EST 2006 | Chunks
Hi Mark, Not to be condescending, but is your 265 camera in focus? I've seen one instance of this. If it�s not the camera, and you are sure all your other parameters are good, , then poor definition can be from bad snap-off or bad gasketing. Snap
Electronics Forum | Tue Jul 30 10:04:51 EDT 2002 | dason_c
Dave, I am very interesting to know about the dewetting or pull back, we are currently use the uP78 paste. Will nitrogen, profile setting help to reduce the dewetting. Thank.
Electronics Forum | Mon Feb 20 20:47:59 EST 2006 | davef
We assume your stencil is clean. So, try: * Reduce stencil separation speed. * Reduce squeegee pressure. If the pressure is not proper, excess number of particles are stuffed into an aperture and inner pressure / friction among particles increase, an
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 09:36:11 EDT 2006 | Steve
Not being funny here but I understand exactly what you are saying and sounds exactly the same as we experienced. Seriously try a different paste. Give Tamura a ring and I am sure they will give you a sample. I don't have the exact part code but they
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
