Electronics Forum | Sun Dec 11 22:39:36 EST 2016 | ppcbs
We have been using the Amtech line for over 12 years now with all of our PCB and BGA Rework. The NWS-4400 is mildly active and will give better results with Lead Free Solder. Note that the LF-4300 is considered a No-Clean. However it will show lea
Electronics Forum | Tue Dec 29 11:40:24 EST 1998 | Michael Allen
I don't have answers...just comments. We're just starting to assemble CSPs on protos, and I've got the same concerns you have. The MicroBGA package I'm working with has a ball diameter of 0.325mm (0.0128") and a standoff of just 0.010" BEFORE solde
Electronics Forum | Mon Feb 11 21:54:14 EST 2002 | davef
LONG TERM Your plans to buy a vaccuum bag resealer and a batch drying oven sound good as you say, but you�re correct. They will not help with this current situation. SHORT TERM If your connections are clean, free of pits and holes with a smooth,
Electronics Forum | Fri Jan 14 16:58:20 EST 2000 | Dave F
Dave: You're probably correct about too much paste, given that your balling is congrigated near the center of the chips. Three things to consider: 1 Lower temperature profile @ front 3 zones 2 I've heard some stencil suppliers can plate addition
Electronics Forum | Fri Jan 14 17:24:08 EST 2000 | John Thorup
Yeah, it would be kind of expensive to replace all of your stencils but it's the only real answer. Be sure that all your new and replacement stencils have a home base or home plate shape for the passives. This reduces the paste volume near the cent
Electronics Forum | Wed Nov 10 18:02:54 EST 1999 | John Thorup
Hi Dave Sounds like what we call a "squeeze ball". Usually caused by excess paste squeezed over the mask between the pads of the component when placed. This sometimes escapes the pull of surface tension back to the fillet and escapes to the side, us
Electronics Forum | Wed May 28 19:21:09 EDT 2014 | hegemon
Just from the look of things (a picture) I would first guess it is a contamination problem on the PWB. Check over all your handling practices. Make sure the PWBs are NEVER touched by bare hands. I would not rule out the Black Pad phenomena, but i
Electronics Forum | Fri May 29 16:07:55 EDT 1998 | Steve Gregory
| | Thanks Steve- | Here is the whole story: | | The solder balls are appearing all over, similar to a | splatter. They are relatively small. We are using H-Technologies | S-HQ no-clean solder paste. The stencil is 6 mil and the boards | are ru
Electronics Forum | Wed Jun 08 13:06:36 EDT 2005 | jimby
You will have to machine the part off down to the top of the balls. Wick solder off from individual sites one at a time. All that will be left is Parylene shell where balls once were. Take an orangestick and alcohol to break up and remove. Tricky par
Electronics Forum | Sat Jul 29 09:10:16 EDT 2006 | davef
Ball Grid Array (BGA). A surface mount technology leadless package with the connectors to the board placed in an array on the bottom of the package. They are attached to the board with tiny balls of solder placed on each contact. Pin Grid Array (P